Gulf and Caribbean Research Volume 22 Issue 1 2010 Endohelminths of a Snake Mackerel^ Gempylus serpens (Trichiuroidea: Gempylidae)^ from the Gulf of Mexico Charles K. Blend Gordon College, chuck.blend(®gordon.edu Norman O. Dronen Texas A&M University, College Station James S. Franks University of Southern Mississippi, jim.franks(®usm.edu George W Benz Middle Tennessee State University DOI: 10.18785/gcr.2201.01 Follow this and additional works at: http:/ / aquila.usm.edu/ gcr & Part of the Marine Biology Commons Recommended Citation Blend, C. K., N. O. Dronen, J. S. Franks and G. W. Benz. 2010. Endohelminths of a Snake Mackerel, Gempylus serpens (Trichiuroidea; Gempylidae), from the Gulf of Mexico. Gulf and Caribbean Research 22 ( 1 ) : 1 -8. Retrieved from http:/ / aquila.usm.edu/ gcr/vol22/ issl / 1 This Article is brought to you for free and open access by The Aquila Digital Community. It has been accepted for inclusion in Gulf and Caribbean Research by an authorized editor of The Aquila Digital Community. For more information, please contact Joshua.Cromwell^usm.edu. Gulf and Caribbean Research Vol 22, 1-8, 2010 Manuscript received May 28, 2009; accepted October 22, 2009 ENDOHELMINTHS OF A SNAKE MACKEREL, GEMPYLU5 SERPENS (TRICHIUROIDEA: GEMPYLIDAE), FROM THE GULF OF MEXICO Charles K. Blend^*, Norman O. Dronen^, James S. Franks^, and George W. Benz"^ ^Department of Biology, Gordon College, 255 Grapevine Road, Wenham, MA 01984, ^Laboratory of Parasitology, Department of Wildlife and Fisheries Sciences, Texas A. i5 1 bo 80 100 Group average Transform: Log(X+1) Resemblance: SI 7 Bray Curtis similarity ( + d) Energy Low ▼ High Moderate ♦ Protected Sampling Site Figure 4 . Cluster Analysis (Broy-Curtis) showing percent similarity of all sites for study 60 ^ Group average Transform: Log(X+1) Resemblance SI 7 Bray Curtis similarity ( + d) 70 >1 1 80 - 90 100 ^ cn in Sampling Month CD Figure 5 . Cluster Analysis (Broy-Curtis) showing increasing percent similarity of oil sampling months for study over time. macroalgal productivity (Dawes 1981, Edwards and Kapraun 1973, Round 1981, Kaldy et al. 1995). In this study bio- mass reached its peak during the spring, with a significant decrease in May. The overall decrease in summer biomass coincided with a decrease in species richness. Benz et al. (1979) found that there is little correlation with a single envi- ronmental factor, suggesting a synergistic effect on biomass. Site differences in this study may be representative of varying levels of wave energy. Agan and Lehman (2001) found that Rhodophyta dominated algal coverage along the Port Aransas jetties. These authors also found that Rhodo- phyta abundance was greater along the channel side of the jetty (low energy) and Chlorophyta abundance was greater along the surf side (high energy). Sites with high levels of 14 Macroalgal Colonization in the NW Gulf Figure 6 . Multidimensional scaling (MDS) plots showing site similarity (two-dimensional distance) over time for the duration of the study. Each MDS plot (A-F) is based on 2 months of data and ore cumulative (A = 2 mo, B = 4 mo, C= 6 mo, etc). Numbers repre- sent sites os in Figure 1 . A. September 2006. B. November 2006. C. January 2007. D. March 2007. E. May 2007. F. July 2007. wave energy have also been found to have increased oven all biomass (Agan and Lehman 2001, Klootwyk 2006). Similar trends in biomass were observed for this study. Quadrats sampled within a particular site showed little similarity (19.96-43.34%). Species of algae typically vary in abundance spatially and temporally, governing algal assem- 15 Fikes and Lehman blages that are patchy in structure and composition (Dayton 1971, Luhchenco 1980, Jernakoff 1985, Foster 1990, Chap' man and Underwood 1998). Variation in wave-exposed rocky shores has been documented when examined at a scale of replicate quadrats, sites, or shores, (Underwood and Chap' man 1997) which has lead to difficulty in examining most benthic communities, including macroalgal assemblages. Site 9 was found to be significantly different from all other sites in all aspects of this study. The stunted develop' ment of this site is likely a direct result of pass ha' thymetry. Data from the Texas Coastal Ocean OU servation Netu^ork (TCOON) reveals that a rather large bottom depression has formed at the end of the north jetty. This pit creates an upwelling of sediments making the area more turbid than others and could account for the decreased richness and biomass. For these reasons, site 9 was excluded when look' ing at community dynamics of the system over time. Increased turbidity from sediment transport in and around the channel may result in a reduction in the water depth at which algal growth occurs. Algal growth along Texas coastal jetties is known to occur at depths of up to 3 m (Britton and Morton 1989). During this study, growth was not found to occur at depths of more than about 1 m. Due to the gradual slope of the jetties at Packery Channel this “zone of algal growth” was analyzed without compromising sampling intensity. Community analysis showed that both saim pling months and sites were significantly diffen ent from one another. When compared to biomass data from Port Mansfield’s macroalgal commu' nity, it is evident that seasonal variation should not be interpreted from this study. Sampling months were all found to be about 60% similar, unlike that of Mansfield Pass, with consecutive sampling events (months) exhibit' ing about 80% similarity (seasonality). This inconsistency may be interpreted as macroalgal community development of Packery Channel and is not representative of true sea' sonal variation of an established macroalgal community. Seven species were found restricted to either the chaiv TABLE 2, Average community dissimilarity (SIMPER) between all sites for Packery Channel study (given os %). Value in parentheses repre- sents the total number of species the sites share. An * indicates that the two sites were significantly different (ANOSIMj. Site 1 2 3 4 7 8 9 10 1 (28) 2 59.59 (22) ( 20 ) 3 *81.97 *77.24 (20) (19) (19) 4 *78.88 *82.74 83.33 (31) (25) (21) (19) 7 *81.71 *87.90 *90.65 *81.76 (33) (26) (20) (18) (27) 8 *86.32 *85.15 91.26 83.34 87.12 (22) (19) (16) (15) (20) (21) 9 *98.13 *97.31 *96.85 *95.13 *94.43 *96.43 (20) (U) (17) (15) (20) (20) (17) 10 *79.80 *83.36 *89.46 79.22 74.93 *84.94*94.12 (26) (23) (18) (16) (24) (23) (19) (19) 16 Macroalgal Colonization in the NW Gulf TABLE 3. Floristic affinities along the Gulf Coast (north to south) using Cheney's Floristic Ratio (R=Rhodophytes, C=Chlorophytes, and P=Phoeophytes [0=Ochrophytes]) (Cheney 1977). Location R C P(0) Cheney Reference Galveston, TX 14 8 5 4.4 Lowe and Cox 1978 Port Aransas, TX 53 21 12 6.2 Edwards and Kapraun 1973 Port Aransas, TX 52 21 14 5.2 Edwards 1 976 Packery Channel, TX 25 1 1 4 9.0 This study Port Mansfield, TX 22 1 1 6 5.1 Klootwyk 2006 South Padre Island, TX 35 17 12 4.3 Sorenson 1979 South Padre Island, TX 76 36 18 6.2 Boca et al. 1979 Veracruz, Mexico 46 34 1 1 7.3 Lehman and Tunnell 1992 nel or surf sides of the jetties at Packery Channel. All of these species exhibited markedly low biomass values and occurred in relatively few samples. The generalization still applies that species vary in their tolerance to surf expo- sure (Widdowson 1964, Kapraun 1980). Energy tolerance may not be the only reason for their habitat restriction. All species with growth limited to one side or the other were also absent by the end of the study, so they may have also been limited in their range due to factors of competition. All sites for this study (with the exception of site 9) were found to be about 55% similar in community struc- ture. Those sites exhibiting the most similarity (e.g., sites 3 and 8, sites 1 and 2) were those with similar location along the jetties and similar levels of wave energy. These data indicate that wave energy (represented by site location and exposure) has a direct affect on colonization of algae. Space and seawater inorganic nutrients are considered to be the limiting resources for macroalgae in most tern- perate systems (Chapman and Craigie 1977, Sousa 1985). Successional studies have shown that disturbance facilitates invasion of species by reducing competitors or increasing resources (D’ Antonio 1993). This is especially true for iiv tertidal habitats where disturbance affects community struc- ture and organization (Dayton 1971). Disturbance for this study may be a result of the continued turbidity caused by resuspended sediments in and around the channel. Although poorly studied, competition is important in most algal communities (Paine 1990) as these processes determine patterns of abundance. Important interactions occur between physical factors, grazing, and levels of inter- specific competition (Graham and Wilcox 2000). Factors and variables are constantly changing within a community, and only those species that are capable of withstanding such pressures continue to thrive. In some cases, opportunistic species rapidly colonize a habitat, and they are thus given the competitive edge for space. Several genera identified in this study have been shown to be opportunistic colonizers, such as Hypnea and Ulva (Biebl 1962, Russell and Balazs 1994). Colonization studies should not be treated in the same manner as successional studies due to differences in factors affecting immigration to substratum. In new habitats, competition is drastically reduced and space is not initially limited. This may be the reason why early colonizers have a markedly higher biomass in proportion to other species. This study is more representative of al- gal colonization than secondary successional studies due to the fact that there was no established algal population in the general area of sampling. This study relies on com- munity development from initial stages of colonization, meaning that only species with propagules in nearshore currents and adjacent habitats had the potential to recruit. This study represented the first report of A. ramosissima from along the Texas coast (Pikes and Lehman 2008b). The occurrence of this species may promote the idea that though our flora shows a tropical affinity, some species may not have the means to compete with native flora. Their re- productive propagules may be present in the water column but never have the chance to stabilize within a community. Both B. cuspidata and B. thyrsigera were found among the top three most abundant species for this study. Bryocladia has been found to dominate the Port Aransas, Port Mansfield, and Galveston jetties as well, indicating that it is a species of major importance along the Texas Gulf Coast (Wardle 1992). These species are typically associated with a “turf’ formation, providing habitat for large numbers of benthic infauna (Valerio -Berardo and Flynn 2002). This makes them very important contributors to overall ecosystem func- tion via bottom-up control. Bottom-up control and top- down control likely act as joint determinants of community structure in rocky intertidal communities (Menge 2000). Grateloupia filicina, a species that is important commer- cially (Wong and Chang 2000) and ecologically, was found to be the second most abundant species collected during the study. It was also found to be the dominant species occurring at Mansfield Pass (Klootwyk 2006). This species is categorized as a thick leathery species, similar to Gracilaria spp., allowing 17 Fikes and Lehman for survival in high energy environments (Littler et al. 1983). This supports the occurrence of G. filicina in large quantities in sites 1 and 2, those with the highest levels of wave energy. Hypnea musciformis was found to be one of the top contributing species for this study, and it is known to be an early colonizer and fastspreading species in mac- roalgal communities around the world. In the Hawaiian Islands, H. musciformis has been introduced into many communities (Russell and Balazs 1994) and has become incorporated into the diet of the green sea turtle {Chelo- nia mydas L.) which is found in great numbers through- out the Coastal Bend region, including Packery Channel. Coralline algae are a conspicuous component of intertidal and shallow subtidal algal turfs, are among the first to recruit into these assemblages, and show a negative correlation be- tw^een abundance and ephemeral coverage (Coleman 2003). Haliptilon cubense and Jania adhaerens were both found oc- curring in the macroalgal turf relatively early in the study (January 2007), but their abundance was very limited. At this time many species of ephemeral algae were found occur- ring within the turf, possibly accounting for the low biomass of corallines. The low abundance could have also been due to the slow growth that these macroalgae typically exhibit. The green algae C. linum was found to develop late in this study, and was most often found occurring in the supratidal splash zone along the jetties. Species of Chaetomorpha, along with Ulva and Bryopsis, are known for their ability to with- stand partial desiccation (Biebl 1962). This element adds to the complexity and diversity of the macroalgal community of Packery Channel, as well as most rocky intertidal communities. Few studies examine the roles of artificial habitats and their ecological role as surrogates to natural communi- ties (Bulleri 2005). Until jetties were constructed along the Texas coast, the outer shores were limited in algal growth because they lacked the necessary hard substratum. Previous Texas algal collections described species of Ulva, Gracilaria, Gelidium and Hypnea as the most dominant mac- roalgae of the Corpus Christ! Bay area (Agan and Lehman 2000). These species are all found dominating the Port Aran- sas jetties. Representatives from each of these genera were also collected from Packery Channel, perhaps providing ad- ditional contributions to the bay community. Possible sourc- es for these macroalgae include Corpus Christ! Bay and the Upper Laguna Madre via water exchange during low tides and nearby coastal jetty communities via longshore currents. Macroalgae immediately began to attach to the rocky sub- stratum and these communities quickly become rich in spe- cies diversity. Though biomass values may be comparable to that of nearby systems, newly forming assemblages show pro- nounced patchiness in community structure. Over time these communities exhibit a more even distribution, with similar site locations showing increased similarity. An increase in energy results in both a decrease in richness and increase in biomass during habitat colonization and development. Acknowledgments Funding for this study was provided by the Hans and Patricia Suter Endowed Scholarship and the Henry Hildebrand Endowed Scholarship funds which support field research. We would like to thank the Center for Coastal Studies for their assistance and support by providing lab space, field transportation, and dive- related equipment for this study. Special thanks are given to S. C’Campo, J. Colmenero, M. Mclver, L. Young, A. Knight, J. Wrast, T. Huckabay and A. Krauss for all of their time and hard work in the lab and field. Literature Cited Agan, J. C. and R.L. Lehman. 2000. Species composition and seasonal periodicity of macroalgal species in Corpus Christ! Bay, Texas. Journal of Phycology 36 (suppl.);L Agan, J. C. and R.L. Lehman. 2001. Seaweed abundance and di- versity in high energy and low energy areas at Port Aransas, Texas jetties. Journal of Phycology 37 (suppl.);4. Atilla, N., M.A. Wetzel, and J.W. Fleeger. 2003. Abundance and colonization potential of artificial bard substrate-associated me io fauna. Journal of Experimental Marine Biology and Ecology 287:273-287. Baca, B.J., L.O. Sorenson, and E.R. Cox. 1979. Systematic list of seaweeds of south Texas. Contributions in Marine Science 22:179-192. Biebl, R. 1962. Seaweeds. In: R.A. Lewin, ed. Physiology and Biochemistry of Algae. Academic Press, New York, NY, USA, p. 799-815. Benz, M.C., N.J. Eiseman, and E.E. Gallaher. 1979. Seasonal occurrence and variation in standing crop of a drift algal community in the Indian River, Elorida. Botanica Marina 22:413-420. Britton, J.C. and B. Morton. 1989. Shore Ecology of the Gulf of Mexico. The University of Texas Press, Austin, TX, USA, 387 p. Bulleri, E. 2005. Role of recruitment in causing differences be- tween intertidal assemblages on seawalls and rocky shores. Marine Ecology Progress Series 287:53-65. Chapman, A.R.O. 1986. Population and community ecology of seaweeds. Advances in Marine Biology 23:1-16. Chapman, M.G. and A.J. Underwood. 1998. Inconsistency and variation in the development of rocky intertidal algal assem- blages. Journal of Experimental Marine Biology and Ecology 224:265-289. 18 Macroalgal Colonization in the NW Gulf Chapman, M.G. and J.S. Craigie. 1977. Seasonal growth in Laminaria longicruris: relations with dissolved inorganic nu- trients and internal reserves of nitrogen. Marine Biology 40: 197-205. Cheney, D.P. 1977. A new and improved ratio for comparing sea- weed floras. Journal of Phycology 13(suppl):12. Coleman, M.A. 2003. Effects of ephemeral algae on coralline re- cruits in intertidal and suhtidal habitats. Journal of Experi- mental Marine Biology and Ecology 282:67-84. D’Antonio, C.M. 1993. Mechanisms controlling invasion of coast- al plant communities hy the alien succulent Carpobrotus edulis. Ecology 74:83-95. Dawes, C.J. 1981. Marine Botany. J. Wiley and Sons, New York, NY, USA, 628 p. Dayton, P.K. 1971. Competition, disturbance and community or- ganization: the provision and subsequent utilization of space in a rocky intertidal community. Ecological Monographs 41:351-389. Edwards, P. 1976. Illustrated Guide to the Seaweeds and Seagrasses in the Vicinity of Port Aransas, Texas. The University of Texas Press, Austin, TX, USA, 128 p. Edwards, P. and D.P. Kapraun. 1973. Benthic marine algae ecol- ogy in the Port Aransas, Texas area. Contributions in Marine Science 17:5 -5 2. Pikes, R.P. 2008. Recruitment and colonization of macroalgal species to the rocky jetties of Packery Channel, Corpus Chris- ti, TX. MS Thesis, Texas A&cM University- Corpus Christi, Corpus Christi, TX, USA, 96 p. Pikes, R.L. and R.L. Eehman. 2008a. Small-scale recruitment of flora to a newly developed tidal inlet in the northwest Gulf of Mexico. Gulf of Mexico Science 26:130-132. Pikes, R.L. and R.L. Lehman. 2008b. The occurrence of Agardhiel- la ramosissima (Gigartinales) and Acanthophora spicifera (Cera- miales) in the Texas Coastal Bend. Texas Journal of Science 60:221-224. Poster, M.S. 1990. Organization of macroalgal assemblages in the Northeast Pacific: the assumption of homogeneity and the il- lusion of generality. Hydrobiologia 192: 21-34. Gaylord, B., D.C. Reed, P.T Raimondi, L. Washburn, and S.R. McLean. 2002. A physically based model for macroalgal spore dispersal in the wave and current-dominated nearshore. Ecol- ogy 83:1239-1251. Graham, L.E. and L.W. Wilcox. 2000. Algae. Prentice Hall, Up- per Saddle River, NJ, USA, 640 p. Jernakoff, P. 1985. Temporal and small-scale spatial variability of algal abundance in an intertidal rocky shore. Botanica Marina 28:145-154. Kaldy, J.E., K.H. Dunton, and AB. Czerny. 1995. Variation in macroalgal species composition and abundance on a rock jetty in the Northwest Gulf of Mexico. Botanica Marina 38:519-527. Kapraun, D. P. 1980. Summer aspect of algal zonation on a Texas jetty in relation to wave exposure. Contributions in Marine Science 23:101-109. Klootwyk, K.V 2006. Seasonal changes in benthic macroalgae composition and abundance at the Mansfield Pass jetties. Port Mansfield, Texas. Master’s Thesis, Texas A&M University- Corpus Christi, Corpus Christi, TX, USA, 77 p. Lehman, R.L. and J.W. Tunnell, Jr. 1992. Species composition and ecology of the macroalgae of Enmedio Reef, Veracruz, Mexico. Texas Journal of Science 44:445-457. Either, M.M., D.S. Either, and P.R. Taylor. 1983. Evolutionary strat- egies in a tropical barrier reef system: functional-form groups of marine macroalgae. Journal of Phycology 19:229-237. Lowe, G.C., Jr. and E.R. Cox. 1978. Species composition and sea- sonal periodicity of the marine benthic algae of Galveston Is- land, Texas. Contributions in Marine Science 21:9-24. Lubchenco, J. 1980. Algal zonation in the New England rocky intertidal community: an experimental analysis. Ecology 61:333-344. Mathieson, A.C. and C.A. Penniman. 1986. A phytogeographic interpretation of the marine flora from the Isles of Shoals, U.S.A. Botanica Marina 29:413-434. Mathieson, AC., E.J. Hahre, and N.B. Reynolds. 1981. Investiga- tion of New England marine algae I: a floristic and descrip- tive ecological study of the marine algae at Jeffery Point, N.H., U.S.A. Botanica Marina 24:521-532. Menge, B.A. 2000. Top-down and bottom-up community regu- lation in marine rocky intertidal habitats. Journal of Experi- mental Marine Biology and Ecology 250:257-289. Paine, R.T 1990. Benthic macroalgal competition: complications and consequences. Journal of Phycology 26:12-17. Pedrini, A. 1984. Algas marinhas bentonicas do litoral Norte- Eluminense. I-Lista preliminar das algas “Arribadas” da Praia de Manguinhos (Guaxindiba - Sao Juao da Barra - Rio de Janeiro). Atas da Sociedade Botanica do Brasil, seccao Rio de Janeiro 2:133-142. Round, E.E. 1981. The Ecology of Algae. Gambridge University Press, Cambridge, UK, 653 p. Russell, D.J. and G.H. Balazs. 1994. Colonization by the alien marine algae Hypnea musciformis (Wulfen) J. Ag. (Rhodophyta: Gigartinales) in the Hawaiian Islands and its utilization by the green turtle, Chelonia mydas L. Aquatic Botany 47:63-60. Santelices, B. 1990. Patterns of reproduction, dispersal and re- cruitment in seaweeds. Oceanography and Marine Biology: an Annual Review 28:177-276. Schneider, C.W. and R.B. Searles. 1973. North Carolina marine algae. II. New records and observations of the benthic offshore flora. Phycologia 12:201-211. Schneider, C.W. and R.B. Searles. 1991. Seaweeds of the South- eastern United States: Cape Hatteras to Cape Canaveral. Duke University Press, Durham, NC, USA, 553 p. Sorenson, L.O. 1979. A Guide to the Seaweeds of South Padre Island, Texas. Gorsuch Scarisbrick, Scottsdale, AZ, USA, 123 p. Sousa, W.P. 1985. Disturbance and match dynamics on rocky intertidal shores. In: S.TA Pickett and P.S. White, eds. The Ecology of Natural Disturbance and Patch Dynamics. Aca- 19 Fikes and Lehman demic Press, New York, NY, USA, p. 101-124. Steneck, R.S. and M.N. Dethier. 1994. A functional group ap- proach to the structure of algal-dominated communities. Oikos 69:476-498. Underwood, AJ. and M.G. Chapman. 1997. Variation in algal as- semblages on wave-exposed rocky shores. Marine and Fresh- water Resources 49:241-254. United States Army Corps of Engineers. 2003. North Padre Island storm damage reduction and environmental restora- tion project. Final Environmental Impact Statement. United States Army Corps of Engineers, Calveston, TX, USA. 297p. Valerio-Berardo, M.T. and M.N. Flynn. 2002. Composition and seasonality of an amphipod community associated to the algae Bryocladia thyrsigera. Brazilian Journal of Biology 62:735-742. van den Hoek, C. 1987. The possible significance of long-range dispersal for the biogeography of seaweeds. Helgolander Meeresuntersuchungen 41:261-272. Wardle, W. J. 1992. Range extension for Porphyra leucosticta Thuret (Rhodophyta:Bangiales) from the central to the up- per Texas coast. Texas Journal of Science 44:117-118. Widdowson, TB. 1964. A survey of the distribution of intertidal algae along a coast transitional in respect to salinity and tidal factors. Journal of the Fisheries Research Board of Canada 22:1425-1454. Wong, S. and J. Chang. 2000. Salinity and light effects on growth, photosynthesis, and respiration of Grateloupia filicina (Rhodophyta). Aquaculture 182:387-395. Wynne, M.J. 2005. A checklist of benthic marine algae of the tropical and subtropical western Atlantic: second revision. Cebruder Borntraeger, Berlin, Germany, 152 p. 20 Gulf and Caribbean Research Volume 22 Issue 1 2010 Do Small, Patchy, Constructed Intertidal Oyster Reefs Reduce Salt Marsh Erosion As Well As Natural Reefs? Alix G. Stricklin University of Southern Mississippi Mark S. Peterson University of Southern Mississippi^ mark.peterson(®usm.edu John D. Lopez University of Southern Mississippi Christopher A. May The Nature Conservancy in Michigan Christina R Mohrman Grand Bay National Estuarine Research Reserve et al DOI; 10.18785/gcr.2201.03 Follow this and additional works at; http://aquila.usm.edu/gcr & Part of the Marine Biology Commons Recommended Citation Stricklin, A. G., M. S. Peterson, J. D. Lopez, C. A. May, C. F. Mohrman and M. S. Woodrey. 2010. Do Small, Patchy, Constructed Intertidal Oyster Reefs Reduce Salt Marsh Erosion As Well As Natural Reefs?. Gulf and Caribbean Research 22 (l); 21-27. Retrieved from http://aquila.usm.edu/gcr/vol22/issl/3 This Article is brought to you for free and open access by The Aquila Digital Community. It has been accepted for inclusion in Gulf and Caribbean Research by an authorized editor of The Aquila Digital Community. For more information, please contact Joshua.Cromwell^usm.edu. Gulf and Caribbean Research Vol 22, 21-27, 2009 Manuscript received November 23, 2009; accepted December 10, 2010 DO SMALL, PATCHY, CONSTRUCTED INTERTIDAL OYSTER REEFS REDUCE SALT MARSH EROSION AS WELL AS NATURAL REEFS? Alix G. Stricklin^ Mark S. Peterson/* John D. Lopez^’®, Christopher A. May/’^ Christina F. Mohrman/’"^ and Mark S. Woodrey^’^ ^Department of Coastal Sciences, The University of Southern Mississippi, 703 East Beach Drive, Ocean Springs, MS 39564, ^Grand Bay National Estuarine Research Reserve, 6005 Bayou Heron Road, Moss Point, MS 39562, ^The Nature Conservancy in Michigan, 101 East Grand River, Lansing, MI 48906, Environmental Cooperative Science Center, Grand Bay National Estuarine Research Reserve, 6005 Bayou Heron Road, Moss Point, MS 39562, ^Mississippi State University, Coastal Research and Extension Center, 1815 Popps Ferry Road, Biloxi, MS 39531, ^Current address: Texas Parks and Wildlife, Coastal Fisheries Division, Brownsville Field Office, 95 Fish Hatchery Rd., Brownsville, TX 78520 Corresponding author: mark.peterson@usm.edu Abstract: One ecological service that oyster reefs provide is stabilization of shorelines through reduced wave energy and erosion from boat traffic, storms, and predominant wind direction. Additionally, increasing sedimentation can enhance the growth of emergent marsh vegetation which further stabilizes unconsolidated sediments. A 21 mo study of constructed (with only 30-35% coverage) and natural oyster reefs in 3 bayous in the Grand Bay National Estuarine Research Reserve (NERR) suggested constructed reefs benefit this retrograding deltaic ecosystem. The marsh edge adjacent to all constructed reefs was less eroded (mean = 0.043 m) than edges adjacent to natural reefs (mean = 0.728 m), although all natural and constructed sites, regardless of bayou, illustrated large variations in marsh edge growth. The marsh edge in constructed sites in one bayou retreated more than in the other bayous, most likely due to its coarser sediments, greater boat traffic, and its apparent higher energy location within the landscape. By the end of this study, the ecological function of constructed oys- ter reefs in all bayous, as measured by marsh edge erosion reduction, was equivalent or exceeded the function in nearby natural oyster reefs. The physical structure of the reef further served to reduce erosion and marsh loss and this approach may be useful for management of a retrograding deltaic estuarine ecosystem like the Grand Bay NERR. Introduction Eastern oyster, Crassostrea virginica, reefs once thrived in the coastal environments of the Atlantic and Gulf of Mexico (GOM) but have declined as a consequence of overharvest- ing and environmental degradation, exacerbated by disease, epizootics, and altered water flow (Breitburg et al. 2000, Coen and Luckenbach 2000, LaPeyre et al. 2003). This loss has not only resulted in diminished harvestable oysters but also plays an important role in the overall degradation of estuaries. Oyster reefs provide fundamental biological, phys- ical, and chemical functions (Rodney and Paynter 2006, Coen et al. 2007, Nestlerode et al. 2007; Beck et al. 2009) that contribute to the persistence of estuarine ecosystems. Because of the economic and ecological value of this special- ized habitat, projects have been conducted at multiple scales to restore subtidal and intertidal oyster reefs to their histori- cal extent. Data on fringe (Cake 1983; hereafter referred to as small), intertidal reefs suggest that they provide unique and necessary habitat for resident and transient estuarine fauna as well as shoreline stabilization (Meyer et al. 1997, Bartol and Mann 1999, Meyer and Townsend 2000, Piazza et al. 2005). The three-dimensional structure of oyster reef habitat, with its high surface area and abundant interstitial space, enhances the value of a reef by: 1) encouraging the settle- ment of oyster spat and other sessile organisms that promote the growth and physical expansion of the habitat (Tolley and Volety 2005, Rodney and Paynter 2006, Powell and Klinck 2007, Gregalis et al. 2008, Gregalis et al. 2009); 2) attract- ing a diversity of infaunal and epifaunal organisms (Powers et al. 2003, Tolley and Volety 2005, Shervette and Gelwick 2008a); 3) increasing prey biomass available to predators, thereby enhancing trophic transfer (Meyer and Townsend 2000, Tolley and Volety 2005, Rodney and Paynter 2006); 4) providing a shallow water refuge in times of stress, such as desiccation stress and seasonal hypoxia (Lenihan et al. 2001) or parasite infestation (LaPeyre et al. 2003); and 5) creat- ing physical barriers that enhance sediment deposition and buffer wave energy, thus increasing marsh area and reduc- ing shoreline erosion (Meyer et al. 1997, Piazza et al. 2005, Coen et al. 2007). These functions become compromised with the large-scale loss of oyster reefs (Hargis and Haven 1999, Boesch et al. 2001, Beck et al. 2009). Adthough oyster reefs are an ecologically and economical- ly valuable estuarine habitat type, few studies have focused on restoration of and ecological services provided by small, intertidal reefs that thrive in the shallow estuaries along the GOM (Piazza et al. 2005, Tolley et al. 2005, Shervette and Gelwick 2008a, b). As part of a larger restoration project 21 Stricklin et al. (Peterson and Stricklin 2008), we examined one ecological service of oyster reefs, marsh edge vegetation stabilization and growth, within three bayous of the Grand Bay National Estuarine Research Reserve (NERR), located in southeast Jackson County, Mississippi. We tested the hypothesis that small, intertidal constructed oyster reefs have similar or eiv hanced shoreline protection capability as nearby natural reefs. Materials and Methods Site description Replicate sites in intertidal areas were selected to com struct oyster reefs and examine shoreline change based on adjacent available oyster habitat, water flow, salinity, sub- strate, and slope suitable for natural seeding and develop- ment of self-sustaining reefs (Cake 1983) in three bayous of the Grand Bay NERR (30°23’N, 88°24W): Bayou Cumb- est. Crooked Bayou, and North Rigolets (Eigure 1). Grand Bay NERR is a marine dominated ecosystem (Peterson et al. 2007) with freshwater input occurring via precipitation, runoff, and inflow from Bayou Cumbest. Tides are mi- crotidal (~0.5 m) and can be wind-driven. The Grand Bay NERR is a retrograding delta with marsh erosion rates rang- ing from 0.5 -4.0 m/yr, with much of the system experienc- ing rates of > 2.5 m/yr (Otvos 2007). Bayou Cumbest is the farthest inland of the three bayous with a well-consolidated clay and sand shore adjacent to a steep, upland erosional marsh edge consisting of Spartina alterniflora and Juncm ro- emarianus. Crooked Bayou is the middle bayou with a poorly consolidated muddy bottom, and is adjacent to S. alterniflora. North Rigolets is located be- tween Point aux Chenes Bay and Middle Bay, is composed of unconsolidated mud, and is adjacent to S. alterniflora. Reef construction and sampling procedures Within each bayou, we constructed 55.8 iW (30.5 m X 1.8 m) intertidal oyster reefs on 17-18 August 2006, and each was set at least 92 m away from a paired nearby natural reef. Each paired set was subject to similar physical conditions within each bayou, and each reef location (constructed or natural) was divided into 3 contiguous sections which served as rep- licates. Within each of these sections, an equal- sized grid of cells was visualized to facilitate the placement of trays (48.26 cm E x 30.48 cm W X 11.43 cm H; Norseman Plastics) with shell bags and/ or shell bags alone (max mesh size = 25.4 mm; same dimensions as trays) during ini- tial reef construction. To simulate the observed patchiness in natural reefs, the constructed reefs were supplemented with shell bags or trays with shell bags (see Peterson and Strick- lin 2008 for details on biological assessment component) filled with about 0.03 m^ (1 fE) of oyster cultch to reach the desired 30-35% cov- erage (a total of 34 bags and trays per section). Shell bags were laid flat on top of the mudflat and trays were dug into the mudflat to be no higher than shell bags, but both were about 15 cm (6 in) above the mudflat. The trays with shell bags and shell bags were deployed in the intertidal zone ben\^een high and low tide, and bags were cut open to mimic natural habitat. The ability of oyster reefs to enhance marsh edge stabilization and growth was assessed using marsh edge stabilization profiles (Meyer et al. 1997). A mid- line transect on each natural and constructed reef replicate section (n = 3) was established with a PVC stake in the marsh Figure J. Sampling sites. A. Mop of the Grand Boy National Estuarine Re- search Reserve, Jackson County, MS and the three bayous sampled. B. Close- up of the locations of the constructed and natural oyster reef pairs in the three bayous. 22 Oyster Reef Stabilization TABLE I. Summary of water qualify conditions pooled over the course of the study (x ± 1 se). There were no significant differences among boyou or hobifof for any variable over the course of the study. Bayou Habitat Temp (“C) Salinity DO (mg/l) Bayou Cumbest Constructed Natural 20.23 ± 2.67 20.45 ± 2.64 20.87 ±2.16 21.33 ± 2.12 7.02 ±1.21 5.70 ±0.61 Crooked Bayou Constructed Natural 21.04 ± 2.31 21.27 ± 2.41 24.16 ± 1.63 24.29 ± 1.47 6.46 ± 0.96 6.57 ± 0.74 North Rigolets Constructed Natural 1 9.87 ± 2.46 20.02 ± 2.45 25.06 ± 1.59 25.10 ± 1.67 5.81 ± 0.95 5.93 ± 0.96 and a PVC stake within the water but immediately upland of the reef boundary. Marsh edge growth was measured as the change in distance (m) between the upland pole and the edge of the marsh grass along the midline transect for each pole set. We attempted to be accurate with measurements of the poles on each sampling event but there may have been some minor error in these measurements over time and space. These data were analyzed as the change in distance over time in comparison to the initial distance measured in August 2006. Monitoring was conducted quarterly over a 21 mo period from November 2006 through June 2008. Sa- linity, water temperature (°C), and dissolved oxygen (mg/L) were measured once per sampling event at each reef location with a YSl model 85 handheld meter. Data analysis Water temperature, salinity and dissolved oxygen were av- eraged over date and compared with a 2-way AN OVA with bayou and habitat as main effects. Results were considered significant if p <0.05 and all data were tested for normality and homogeneity of variance prior to AN OVA. All 3 vari- ables met these assumptions. Marsh edge growth was examined between habitat type (natural, n = 3 and constructed, n = 3 reefs) and bayou (n = 3) (bet\\^een-subjects factors) and across time (quarters, n = 7) (within-subjects factor) with a split-plot ANOVA (Green and Salkind 2008). If a significant F-value was noted for the between -subjects component of the analy- sis, mean values were evalm ated with a post-hoc Sidak test. For the within-subject component, we adjusted the degrees of freedom with the Greenhouse -Geisser epsilon value (Field 2005, Green and Salkind 2008). Significant F- values for within-subject fac- tors (change over time) were followed up with paired-t tests between all possible time periods, and adjusted with a sequential Bonferroni technique (Rice 1989), reduc- ing the chance of a Type 1 error in making multiple pairwise comparisons. However, because Bonferroni adjustments are very conservative, we chose to balance making a Type 1 or Type 11 error by using p = 0.10; data were analyzed using SPSS (version 15.0). Results were considered significant if p < 0.05 except where noted above and all data were tested for normality and homogeneity of variance prior to ANOVA. Data for marsh edge growth were untransformed. Also, if a significant interaction term was indicated for the between- subjects main effects, the F-values and partial eta squared (partial effect size) values were compared to aid in inter- preting the importance of the main effects relative to the interaction term(s). Partial is the proportion of the total variation attributable to a factor excluding the other main and interaction factors (Green and Salkind 2008). The val- ues range from 0 to 1, with higher numbers having a greater effect size. For consistency, all interaction terms are present- ed in the B x H (i.e., bayou x habitat type) format. One of the marsh edge transect poles was vandalized from one con- structed site in Bayou Cumbest in May 2007 limiting the analysis to only 2 replicates from that point forward. Results Water temperature, dissolved oxygen and salinity between bayou and habitat (constructed and natural) were similar and not significantly different (p > 0.05) over the course of this TABLE 2, Summary of split plot ANOVA statistics, the follow-up Sidok pairwise multiple comparisons (between-subjects), and poired-t tests (within-subjects). B = boyou, H = habitat, Q = reverse time (quarter), BC = Bayou Cumbest, CB = Crooked Boyou, NR = North Rigolets, C (c) = constructed, N (n) = noturol. Quarter (time): I = November 2006, 2 = February 2007, 3 = May 2007, 4 = August 2007, 5 = December 2007, 6 = March 2008, 7 = June 2008. Bold values are significantly different within columns. Measure Overall test p-value (F-value, partial ii^) Bayou comparison (Z distance ± 1 se) Habitat (X distance ± 1 se) Quarter (time) Marsh edge distance (m) B = 0.389 (1.031, 0.158) H = 0.002 (17.066, 0.608) B*H = 0.001 (14.353, 0.723) Q < 0.001 (12.988,0.541) B(Q) < 0.001 (4.926, 0.472) H(Q) < 0.001 (5.274, 0.324) B*H(Q) < 0.001 (6.782, 0.552) BC > CB > NR (BC: -0.212, 0.154) (CB: -0.463, 0.138) (NR: -0.483, 0.138) C > N (C: -0.043, 0.122) (N: -0.728, 0.113) BCc BCn CBc = 1 >4 CBn = 1 >(6=7), 3>2 NRc NRn 23 Stricklin et al. Collection Date Figure 2, Plots of change in marsh edge growth (m, X± 1 se) since August 2006 by bayou (n = 3) and habitat type (n = 2) over the course of the study. Plotted measurements by habitat are offset laterally from the dotes for clarity; actual sampling was conducted over a 1-2 day period during all events. Note the different y-oxis scales for the three graphs. For some dotes, se was smaller than the size of the symbol used for the mean value. • - constructed sites; X - natural sites. study (Table 1). The lowest temperatures were observed in November 2006 and December 2007 (11.9-14.5°C) and the highest in August 2007 and June 2008 (26.5-29.8°C). Dis- solved oxygen varied 3.37-13.60 mg/L in Bayou Cumbest, 2.87 -9.70 mg/L in Crooked Bayou and 2.37 - 10.40 mg/L in North Rigolets. Salinity varied 18.4-29.1 in Crooked Bayou and 18.3-28.8 in North Rigolets, and Bayou Cumbest had the lowest salinity (11.6-29.3). There was an overall erosion of marsh edge over the course of this study at all sites. Although no differences were noted among bayous (Table 2), marsh edge growth did vary significantly betw^een constructed and natural oyster reefs within all three bayous and over time in Crooked Bayou (Figure 2). This variation was accounted for by significant interaction effects among combinations of bayou, habitat and time (quarter), but each had small F-values and moden ate partial values (Table 2). For example, in Bayou Cumb- est marsh edge advanced at the constructed reef through May 2007 and retreated during the remainder of the study. In natural reefs, the marsh edge did not change through December 2007 and then retreated through June 2008 (Figure 2). In contrast. Crooked Bayou marsh edge growth was stable in constructed reefs over time except June 2008 (Figure 2), but natural reefs had positive marsh edge growth betv^een February and May 2007, though overall reductions occurred between November 2006 and June 2008 (Figure 2, Table 2). In North Rigolets, there was slow retreat of marsh edge in the constructed reefs over time while the natural reefs exhibited high variability and an overall retreat over time (Figure 2). Overall, there were significant main effects of habitat, time, and B x H interaction effects, with high F- values and moderate to high partial r\^ values (Table 2), indF eating less retreat of the marsh edge in the constructed reefs compared to the natural reefs in all bayous (Table 2). The greatest source of variation was associated with the interac- tion effect of bayou x habitat (Table 2), with Bayou Cumbest exhibiting more retreat of the marsh edge in constructed versus natural reefs. In contrast. Crooked Bayou and North Rigolets marsh edge retreat was more pronounced in natm ral relative to constructed reefs (Figure 2). Variability (larger se) in marsh edge growth in natural reef sites was greater than constructed sites in North Rigolets and Crooked Bay- ou compared to Bayou Cumbest (Figure 2). Mean overall marsh edge retreat was 0.728 m for natural and 0.043 m for constructed oyster reefs. Discussion One goal of habitat restoration is to develop a functional habitat where one did not previously exist, or to rehabilF tate a degraded habitat (Simenstad et al. 2006) such that system productivity and ecosystem services are enhanced. We determined that constructed oyster reefs slowed the rate of erosion more than nearby natural reefs in the Grand Bay NERR; mean marsh edge retreat was 0.035 m/mo (0.728 Oyster Reef Stabilization m overall) for natural and 0.002 m/mo (0.043 m overall) for constructed oyster reefs. This pattern varied by bayou, however, with the least overall marsh edge retreat at Bayou Cumbest, followed by Crooked Bayou and North Rigolets. Though there were temporal differences noted on all reefs among the three bayous, these changes were most visible at the natural reefs in Crooked Bayou and constructed reefs in Bayou Cumbest. Rates of retreat were similar to that found by Piazza et al. (2005) in Louisiana, who reported a mean overall retreat of 0.08 m/ mo (1.68 m overall) in added cultch sites and 0.12 m/mo (2.52 m overall) in noivcultched sites. Though there was no overall mean growth in the marsh edge (except Bayou Cumbest natural sites), the reduced retreat in marsh edge adjacent to constructed oyster reefs highlights the ability of these reefs (representing only 30-35% coven age) to reduce shoreline erosion under the environmental conditions at our sites. It is possible that greater oyster shell coverage on these small intertidal reefs may further retard erosion or enhance sediment accretion and thus growth of the marsh edge. We had three concerns about our marsh edge growth measurements. First, the PVC posts used for marking the upland to lowland transect may have been subject to move- ment due to weather and wave action because some stakes during the course of the study appeared to be leaning a bit out of the vertical. To minimize intenobserver variability, we had the same individuals make each set of measurements. Second, short-term studies such as this one may not en- compass the full spectrum of conditions, which may have revealed sustained advances or retreats in marsh edge at con- structed reefs over a longer time period. A North Carolina study of similar duration (Meyer et al. 1997; 20 mo) found little difference between cultched and non-cultched reefs. However, Meyer et al. (1997) reported a mean advance of 0.26 m over 20 mo, with growth varying by reef location (orientation to wind and wave action); a greater percent cover of oyster shell was also used compared to the Grand Bay NERR sites. Clearly, longer study duration would allow for more accumulation or erosion of sediments along the marsh edge; however, the construction of reefs with oyster cultch within Grand Bay NERR appears to provide some protection of salt marsh shorelines, as has been found in Eouisiana (Piazza et al. 2005). Einally, differences existed in sediment composition between sites that may have in- fluenced sediment accretion patterns and erosion. Bayou Cumbest sites had more consolidated clay/ sandy sediments whereas at the other two locations, sediments were uncon- solidated and muddy. North Rigolets and Crooked Bayou exhibited more erosion than elsewhere, most likely from orientation to the constant southeast wind direction and the fact that Bayou Cumbest had a bit more protection from upland trees than the other two locations. This is consistent with findings by Piazza et al (2005), who proposed that inter- tidal reefs work better to stabilize marsh edge in low energy than high energy sites. As ecosystem engineers (}ones et al. 1994, Micheli and Pe- terson 1999), oysters and the reefs they create provide habi- tat and stabilize shorelines by buffering wave energy and mitigating erosion caused by boat traffic, storms, and pre- dominant wind direction. Eurthermore, by increasing rates of sedimentation they can enhance the growth of emergent marsh vegetation thereby further stabilizing unconsolidat- ed sediments (Coen et al. 1999, Mann 2000, Piazza et al. 2005). By the end of the study, the ecological function of the constructed reefs, as measured by reduction in marsh edge erosion, was equivalent or exceeded the function of nearby natural oyster reefs. The use of small, intertidal reefs to reduce marsh retreat may be a useful management tool to mitigate retrograding deltaic estuarine ecosystems like the Grand Bay NERR. Acknowledgments We thank the USM Office of Research for a Ph.D Eellowship to the senior author, the Coastal Program of the Alabama Nature Conservancy (N. Vickey and M.A. Eott) and the Grand Bay NERR (D. Ruple) for financial sup- port of this project. Paul Crammer, M. Eowe, E. Eang, and J. Mcllwain supported this research with logistics and field work. Two external reviews made the manuscript clearer and more focused. Literature Cited Bartol, I.K. and R. Mann. 1999. Small-scale patterns of recruit- ment on a constructed intertidal reef the role of spatial refu- gia. In: M.W. Luckenbach, R. Mann, and J.A. Wesson, eds. Oyster Reef Habitat Restoration: A Synopsis and Syntbesis of Approaches. Virginia Instimte of Marine Science Press, Gloucester Point, VA, USA, p. 159-170. Beck, M.W., R.D. Brumbaugh, L. Airoldi, A. Carranza, L.D. Coen, C. Crawford, O. Defeo, G.J. Edgar, B. Hancock, M. Kay, H. Lenihan, M.W. Luckenbach, C.L. Toropova, and G. Zhang. 2009. Shellfish at Risk: A Global Analysis of Prob- lems and Solutions. The Nature Conservancy, Arlington, VA, USA. 52 p. Boescb, D., E. Burreson, W. Dennison, E. Houde, M. Kemp, V. Kennedy, R. Newell, K. Paynter, R. Orth, R. Ulanowicz, C. Peterson, J. Jackson, M. Kirby, H. Lenihan, B. Bourque, R. Bradbury, R. Cooke, and S. Kidwell. 2001. Factors in the de- cline of coastal ecosystems. Science 293:1589-1591. Breitburg, D.L., L.D. Coen, M.W. Luckenbach, R. Mann, M. Posey, and J.A. Wesson. 2000. Oyster reef restoration: con- vergence of harvest and conservation strategies. Journal of 25 Stricklin et al. Shellfish Research 19:371-377. Cake, E.W Jr. 1983. Habitat suitability index models: Gulf of Mexico American Oyster. U.S. Department of the Interior, Fish and Wildlife Service. FWS/OBS-82/ 10.57. 38p. Coen, L.D. and M.W. Luckenbach. 2000. Developing success cri- teria and goals for evaluating oyster reef restoration: ecologi- cal function or resource exploitation. Ecological Engineering 15:23-343. Coen, L.D., D.M. Knott, E.L. Wenner, N.H. Hadley, A.H. Ring- wood, and M.Y. Bobo. 1999. South Carolina intertidal oyster reef studies: design, sampling, and focus for evaluating habi- tat value and function. In: M.W. Luckenbach, R. Mann, and J.A Wesson, eds. Oyster Reef Habitat Restoration: A Synop- sis and Synthesis of Approaches. Virginia Institute of Marine Science Press, Gloucester Point, VA, USA, p. 133-158. Coen, L.D., R.D. Brumbaugh, D. Bushek, R. Grizzle, M.W. Luck- enbach, M.H. Posey, S.P. Powers, and S.G. Tolley. 2007. Eco- system services related to oyster restoration. Marine Ecology Progress Series 351:303-307. Field, A. 2005. Discovering Statistics Using SPSS, 2""* edition. Sage Publications, London, UK, 779 p. Green, S.B. and N.L. Salkind. 2008. Using SPSS for Windows and Macintosh. Analyzing and Understanding Data. 5* Edi- tion, Pearson Prentice Hall, Upper Saddle River, NJ, USA, 459 p. Gregalis, K.C., S.P. Powers, and K.L. Heck. 2008. Restoration of oyster reefs along a bio-physical gradient in Mobile Bay, Ala- bama. Journal of Shellfish Research 27:1163-1169. Gregalis, K.C., M.W. Johnson, and S.P. Powers. 2009. Restored oyster reef location and design affect responses of resident and transient fish, crab, and shellfish species in Mobile Bay, Alabama. Transactions of the American Fisheries Society 138:314-327. Hargis, Jr., W.J. and D.S. Haven. 1999. Chesapeake oyster reefs, their importance, destruction, and guidelines for restoring them. In: M.W. Luckenbach, R. Mann, and J.A. Wesson, eds. Oyster Reef Habitat Restoration: A Synopsis and Synthesis of Approaches. Virginia Institute of Marine Science Press, Gloucester Point, VA, USA, p. 329-358. Jones, C.G., J.H. Lawton, and M. Shachak. 1994. Organisms as ecosystems engineers. Oikos 69:373-386. LaPeyre, M.K., AD. Nickens, A.K. Volety, G.S. Tolley, and J.F. La Peyre. 2003. Environmental significance of freshets in reduc- ing Perkinsus marinus infection in eastern oysters Crassostrea virginica: potential management applications. Marine Ecology Progress Series 248:165-176. Lenihan, H.S., C.H. Peterson, J.E. Byers, J.H. Grabowski, G.W. Thayer, and D.R. Colby. 2001. Cascading of habitat degra- dation: oyster reefs invaded by refugee fishes escaping stress. Ecological Applications 11:764-782. Mann, R. 2000. Restoring the oyster reef communities in the Chesapeake Bay: a commentary. Journal of Shellfish Re- search 19:335-339. Meyer, D.L. and E.C. Townsend. 2000. Faunal utilization of cre- ated intertidal eastern oyster (Crassostrea virginica) reefs in the southeastern United States. Estuaries 23:34-45. Meyer, D.L., E.C. Townsend, and G.W. Thayer. 1997. Stabiliza- tion and erosion control value of oyster cultch for intertidal marsh. Restoration Ecology 5:93-99. Micheli, F. and C.H. Peterson. 1999. Estuarine vegetated habitats as corridors for predator movements. Conservation Biology 13:869-881. Nestlerode, J.A., M. Luckenbach, and F.X. O’Beirn. 2007. Settle- ment and survival of the oyster Crassostrea virginica on created oyster reef habitats in Chesapeake Bay. Restoration Ecology 15:273-283. Otvos, E.G. 2007. Geological framework and evolutionary his- tory. In: M.S. Peterson, G.L. Waggy and M.S. Woodrey, eds. Grand Bay National Estuarine Research Reserve: An Ecologi- cal Characterization. Grand Bay National Estuarine Research Reserve, Moss Point, MS, USA, p. 22-47. Peterson, M.S. and A.G. Stricklin. 2008. Restoration and faunal composition of patchy, small intertidal Crassostrea virginica oyster reefs within the Grand Bay National Estuarine Re- search Reserve, north-central Gulf of Mexico. Final report. The Nature Conservancy, Alabama Coastal Program, Mo- bile, AL, USA, 49 p. Peterson, M.S., G.L. Waggy and M.S. Woodrey (eds.). 2007. Grand Bay National Estuarine Research Reserve: An Ecologi- cal Characterization. Grand Bay National Estuarine Research Reserve, Moss Point, MS, USA, 268 p. Piazza, B.P., P.D. Banks, and M.K. La Peyre. 2005. The potential for created oyster shell reefs as a sustainable shoreline protec- tion strategy in Louisiana. Restoration Ecology 13:499-506. Powell, E.N. and J.M. Klinck. 2007. Is oyster shell a sustainable es- tuarine resource? Journal of Shellfish Research 26:181-194. Powers, S.P., J.H. Grabowski, C.H. Peterson, and W.J. Lindberg. 2003. Estimating enhancement of fish production by off- shore artificial reefs: uncertainty exhibited by divergent sce- narios. Marine Ecology Progress Series 264:265-277. Rice, W.R. 1989. Analyzing tables of statistical test. Evolution 43:223-225. Rodney, W.S. and K.T Paynter. 2006. Comparisons of macrofau- nal assemblages on restored and non-restored oyster reefs in mesohaline regions of Chesapeake Bay in Maryland. Journal of Experimental Marine Biology and Ecology 335:39-51. Shervette, VR. and F. Gelwick. 2008a. Seasonal and spatial varia- tions in fish and macro -invertebrate communities of oyster and adjacent habitats in a Mississippi estuary. Estuaries and Coasts 31:584-596. Shervette, V.R. and F. Gelwick. 2008b. Habitat-specific growth in juvenile pinfish. Transactions of the American Fisheries Society 136:445-451. Simenstad, C., D.J. Reed, and M. Ford. 2006. When is restora- tion not? Incorporating landscape-scale processes to restore self-sustaining ecosystems in coastal wetland restoration. Ecological Engineering 26:27-39. 26 Oyster Reef Stabilization Tolley, S.G. and A.K. Volety. 2005. The role of oysters in habitat Tolley, S.G., A.K. Volety, and M. Savarese. 2005. Influence of use of oyster reefs by resident fishes and decapod crustaceans. salinity on the habitat use of oyster reefs in three southwest Journal of Shellfish Research 24: 1007 - 1012. Florida estuaries. Journal of Shellfish Research 24: 127 - 137. 27 Gulf and Caribbean Research Volume 22 Issue 1 2010 Observations on the Kalliapseudid Tanaidacea (Crustacea: Malacostraca: Peracarida) from the Northwestern Atlantic^ with an Illustrated Key to the Species David T. Drumm University of Southern Mississippi Richard W Heard University of Southern Mississippi, richard.heard^usm.edu DOI; 10.18785/gcr.2201.04 Follow this and additional works at: http:/ / aquila.usm.edu/ gcr & Part of the Marine Biology Commons Recommended Citation Drumm, D. T. and R. W. Heard. 2010. Observations on the Kalliapseudid Tanaidacea (Crustacea: Malacostraca: Peracarida) from the Northwestern Atlantic, with an Illustrated Key to the Species. Gulf and Caribbean Research 22 (l): 29-41. Retrieved from http://aquila.usm.edu/gcr/vol22/issl/4 This Article is brought to you for free and open access by The Aquila Digital Community. It has been accepted for inclusion in Gulf and Caribbean Research by an authorized editor of The Aquila Digital Community. For more information, please contact Joshua.Cromwell^usm.edu. Gulf and Caribbean Research Vol 22, 29-41, 2010 Manuscript received November 12, 2009; accepted January 19, 2010 OBSERVATIONS ON THE KALLIAPSEUDID TANAIDACEA (CRUSTACEA: MALACOSTRACA: PERACARIDA) FROM THE NORTHWESTERN ATLANTIC, WITH AN ILLUSTRATED KEY TO THE SPECIES David T. Drumm and Richard W. Heard Department of Coastal Sciences, The University of Southern Mississippi, 703 East Beach Drive, Ocean Springs, MS 39564, e-mail: david.drumm@ usm.edu Abstract: New information for the kalliapseudid Tanaidacea occurring in the northwestern Atlantic is presented and discussed, including data on range extensions and new depth ranges for 4 species. The taxa studied came from the shelf and coastal waters of the southeastern United States, Puerto Rico and Trinidad. The occurrence of Mesokalliapseudes baba- mensis Sieg is extended from the Bahamas and Belize to the coastal waters of East and Gulf coasts (South Carolina to West Florida). The range of Psommokolliopseudes granulosus Brum is expanded northward into the eastern Gulf of Mexico and new locality records for this species are established for Tobago and Puerto Rico. Mesokalliapseudes brosiliensis (Bacescu), previously known from the southwestern Atlantic off Brazil, is reported from the coastal waters off Trinidad. The range of Tonopseudes gutui Hansknecht, Heard, and Bamber is expanded northward into the eastern Gulf of Mexico. New depth ranges are established for Alokalliopseudes mocsweenyi (Drumm) (82 m), M. bohamensis (52 m), P. granulosus (53 m), and T. gutui (82 m). An offshore form of A. macsweenyi occurs at depths ranging from 10-82 m on the inner and mid con- tinental shelf off the west coast of Florida (Gulf of Mexico); it differs from the coastal form by the shape and dentition of the male and female chelipeds. Synonymies, diagnoses, life history remarks, and an illustrated key to the seven kalliapseudid species known from the NW Atlantic are presented. Introduction Currently 41 species representing 12 genera and 3 sub- families comprise members of the tanaidacean family Kab liapseudidae Lang, 1956 (Amderson 2009, Drumm et al. 2009). Kalliapseudids are distributed throughout the world’s tropical, subtropical, and temperate coastal waters and with few known exceptions, are restricted to depths of less than 200 m (D.T. Drumm, pers. obser.). Within estuarine and shelf waters of the north Atlantic region the family is pres- ently comprised of 6 nominal species contained in 4 genera and 2 subfamilies. In an unpublished master’s thesis, McSweeny (1968) pre- sented the first well- documented discovery for a kalliapseud- id from the NW Atlantic. His detailed and well- illustrated description for ^^Kalliapseudes sp. A” (now Alokalliapseudes macsweenyi (Drumm, 2003)] was based on specimens from southeastern Florida. The report of Gardiner (1973) for Cin ratodactylus floridensis Gardiner, 1973 (now Psammokalliap- seudes granulosus Brum, 1973) represents the first published record for the family from the region. Since then, descrip- tions and records for 4 additional kalliapseudids, Mesokal- liapseudes bohamensis Sieg, 1982, M. soniadawnae Bamber, 1993, M. thalasispeleus Gutu, 2006; and Tanapseudes gutui Hansknecht, Heard and Bamber, 2002 from the northwest- ern Atlantic region have been published. This report deals with a review and the presentation of new information on the occurrence of members of the fam- ily Kalliapseudidae from the northwestern Atlantic. Besides new range and locality records, we present diagnoses, synon- ymies, an illustrated key, and remarks on the life histories, ecology and taxonomy for the kalliapseudid species known to occur in the northwest Atlantic region. The information presented here will be invaluable to future studies on the ecology, biogeography and phylogeography of the Kalliap- seudidae. This paper was borne partly out of the senior au- thor’s dissertation on the systematic revision of the tanaid- acean family Kalliapseudidae. Materials and Methods The total length (TL) of specimens was measured from the tip of the rostrum to the tip of the pleotelson. Material from the Mississippi-Adabama-Florida Outer Gontinental Shelf Study (MAFLA) has been retained at the Gulf Goast Research Laboratory (GGRL) Museum, Ocean Springs, MS, USA. Morphological terminology follows Larsen (2003). Syironymies of described species, including references to pages and figures in original descriptions, are listed immedi- ately underneath each species. Abbreviations for museums, institutions and research programs used: GGRL, Gulf Goast Research Laboratory; MAFLA, Mississippi-Adabama-Florida Outer Gontinental Shelf Study; MHN, Museum National d’Histoire Naturelle, Grigore Amtipa, Romania; MZUSP, Museu de Zoologia, Universidade de Sao Paulo; NHM, Natural History Muse- um, London, UK; NMW, National Museum of Wales, Gar- diff, UK; SGDNR, South Garolina Department of Natu- ral Resources; SERTG, Southeastern Regional Taxonomic 29 Drumm and Heard Laboratory, Charleston South Carolina; USNM: National Museum of Natural History, Smithsonian Institution, Washington DC, USA; ZMK: Zoologisches Museum der ChristiaivAlbrechtS'Universitat, Kiel, Germany. Results and Discussion Systematics Suborder Apseudomorpha Sieg, 1980 Family Kalliapseudidae Lang, 1956 Subfamily Kalliapseudinae Lang, 1956 Genus Alokalliapseudes Gutu, 2006 Mesokalliapseudes Lang, 1956 (in part) Revised Diagnosis: Antenna third article with ventromedi- al smooth and blunt triangular projection; last peduncle ar- ticle lacking double row of plumose setae. Mandibular palp terminally with setulate seta shorter than others. Cheliped sexually dimorphic (male propodus more robust and with differing cutting edge dentition compared to female); ex- opodite absent. Pereopod 1 lacking exopodite. Pereopods 2 and 3 dactylus with thin, proximal digitiform prolongation ending in sensory setae; unguis absent. Pereopods 4 and 5 dactylus short and terminating in tuft of sensory setae; un- guis absent. Pereopod 6 dactylus sexually dimorphic (longer in males) and with one subterminal seta. Pleopod exopodite biarticulate. Pleotelson with two terminal long plumose se- tae. Uropod exopodite with one small round basal article and two larger distal articles. Remarks: Gutu (2006) elevated all four of Lang’s (1956) kalliapseudid subgenera to full generic rank and erected the monotypic genus Alokalliapseudes to receive Kalliapseudes (Mesokalliapseudes) macsweenyi Drumm, 2003. Gutu (2006) distinguished Alokalliapseudes from Mesokalliapseudes primar- ily by the presence of sexually dimorphic chelipeds. The ge- neric status of Alokalliapseudes is presently being reevaluated by one of us (DTD) using both morphological and molecu- lar criteria. Alokalliapseudes macsweenyi (Drumm, 2003) (Figures 1-3, 14B, D, E) Kalliapseudes (Mesokalliapseudes) macsweenyi Drumm 2003: 1-12, figures 1-5 Kalliapseudes macsweenyi: Drumm 2004: 137; 2005:203. Alokalliapseudes macsweenyi Gutu 2006: 159, figures 253-261 Kalliapseudes sp. AMcSweeny 1968: 28-40, figures 1-7. Diagnosis: Fully diagnosed and described by Drumm (2003). Material Examined: Coastal and near shore sites; Para- types (USNM 1016974, 5 females and 5 males), NW At- lantic, John U. Lloyd State Park, Whiskey Creek, Dania Beach, FL, tidal creek draining mangrove habitat running parallel to beach, 26°05’N, 80°06’W, 0.5 m depth; 3 males and 2 females (USNM 107021), Alligator Harbor, Franklin Figure I. Alokolliopseudes macsweenyi 'offshore morph/ dorsal view of adult mole (loterol pleonite setae mostly shown only by their bases). Scale bar = 0.5 mm. County, FL, littoral sand- mud bar, 6 June, 1960, coll. (Sc ident. C.E. King; several adult males and females were examined in the fol- lowing locations: Et. Pierce, PE, 27°30’N, 80‘’20’W; Eong Key, PE, 24°49’N, 80°48’W; Tampa Bay, PE, 27°37.9’N, 82°39.4W; Panama City, PE, 30°09’N, 85°41W; Horn Island, MS, 30°15’N, 88°43’W; Petit Bois Island, MS, 30°12’N, 88°25’W. Off shore sites (all from the MAPEA); Adult female with oostegites. Station 2747, 27°24.2’N, 84°07.3’W, 74 m, medium fine sand, Sep- tember 1977; adult male, station 2211, 27°56’29.5”N, 83°52’59.5”W, 43 m, coarse sand, Pebruary 1978; 2 adult females and 1 adult male (4.2 mm TE), sta- tion 2640, 29°43’29.3”N, 87°54’30.3”W, 35 m, me- dium sand, September 1977; 2 adult females and 2 adult males, station 2104-05, 26°25’N, 83°23’00.8”W, 53 m, coarse sand, November 1977; 1 male, 1 female, 2 ju- veniles, station 2104-06, 26°25’N, 83°23’00.8”W, 53 m, coarse sand, November 1977; 2 males, station 2104-07, 26°25’N, 83°23’00.8”W, 53 m, coarse sand, November 1977; 1 female, 4 males, 3 juveniles, station 2104-08, 26°25’N, 83°23’00.8”W, 53 m, coarse sand, November 1977; 6 fe- males, 1 juvenile, station 2104-10, 26°25’N, 83°23’00.8”W, 53 m, coarse sand, November 1977; 2 females with oosteg- ites, station 2104- H, 26°25’N, 83°23’00.8”W, 53 m, coarse sand, November 1977; 1 male, station 2104-G, 26°25’N, 83°23’00.8”W, 53 m, coarse sand, September 1975; 1 female with oostegites, 1 juvenile, station 2207-3, 27°57’00.4”N, 83°09’00.3”W, 19 m, fine-very fine sand, November 1977; 2 females, station 2207-05, 27°57’00.4”N, 83°09’00.3”W, 30 Tanaidacea from the Northwestern Atlantic Figure 2, Chelipeds of Alokolliopseudes mocsweenyi 'offshore morph' A-C. Female with oostegites. D. Ovigerous female. E, F. Adult male. C. Subadult male. Scale bar = 0.2 mm. 19 m, fine -very fine sand, November 1977; 4 juveniles, sta- tion 2207-07, 27°57’00.4”N, 83°09’00.3”W, 19 m, fine- very fine sand, November 1977; 2 males, station 2207-10, 27°57’00.4”N, 83°09’00.3”W, 19 m, fine -very fine sand, November 1977; 1 juvenile, station 2207-11, 27°57’00.4”N, 83°09’00.3”W, 19 m, fine -very fine sand, November 1977; 1 ovigerous female, station 2211-08, 27°56’29.5”N, 83°52’59.5”W, 43 m, coarse sand, February 1978; 1 female withoostegites, station 2316-J,28°42’00.3”N,84°20’00.7”W, 35 m, silty fine sand, November 1977; 1 female with oosteg- ites, 1 female with emptied marsupium, 1 male, 3 juveniles, station 2419-C, 29°46’59.8”N, 84°05’00.2”W, 10 m, me^ dium fine sand; 1 female with oostegites, station 2419 -D, 29°46’59.8”N, 84°05’00.2”W, 10 m, medium fine sand, February 1975; 2 females, 1 male, 1 juvenile, station 2419-E, 29°46’59.8”N, 84°05’00.2”W, 10 m, medium fine sand, February 1975; 1 female with oostegites, 3 males, 1 juvenile, station 2419-F, 29°46’59.8”N, 84°05’00.2”W, 10 m, me- dium fine sand, February 1975; 1 ovigerous female, station 2419-Z, 29°46’59.8”N, 84°05’00.2”W, 10 m, medium fine sand, February 1975; 1 ovigerous female, station 2423-A, 29°37’00.8”N, 84°17’00.2”W, 19 m, silty fine sand, 1975; 1 male, station 2423-F, 29"37’00.8”N, 84°17’00.2”W, 19 m, silty fine sand, September 1977; 1 female with oostegites, 1 male, station 2423-G, 29°37’00.8”N, 84°17’00.2”W, 19 m, silty fine sand, February 1975; 1 male, station 2423-H, 29°37’00.8”N, 84°17’00.2”W, 19 m, silty fine sand, 1976; 1 male, 1 juvenile, station 2423-1, 29°37’00.8”N, 84°17’00.2”W, 19 m, silty fine sand, February, 1975; 1 ju- venile, station 2423-K, 29°37’00.8”N, 84°17’00.2”W, 19 m, silty fine sand; 1 female with oostegites, station 2424-B, 29°13’00.7”N, 85°00’01.4”W, 27 m, medium sand, 1976; 1 female, station 2424-1, 29n3’00.7”N, 85°00’01.4”W, 27 m, medium sand, February 1975; 1 male, station 2426-E, 28°57’59.4”N, 85°23’00.2”W, 82 m, fine sand, 1975; 2 females with oostegites, station 2528-C, 29°54’58.6”N, 86°04’58.5”W, 37 m, coarse sand; 1 female with oostegites, 1 male, station 2528-J, 29°54’58.6”N, 86°04’58.5”W, 37 m, coarse sand, Eebruary 1978; 1 male, station 2533-C, 29°42’59.9”N, 85n5’28.6”W, 67 m, coarse sand; 1 female with oostegites, station 2642-E, 29°40.5’N, 87°37’W, 36 m, medium sand; 2 females, 2 juveniles, station 2747-10, 27°24.2’N, 84°07.3’W, 74 m, medium fine sand, August 1977; 4 males, 2 juveniles, 1 manca, 27°24.2’N, 84°07.3’W, 74 m, medium fine sand, August 1977; 2 females, station 2748-03, 27°37.2’N, 83°53.5’W, 50 m, coarse sand, No- vember 1977; 1 female with oostegites, 1 male, station 2748-05, 27”37.2’N, 83°53.5’W, 50 m, coarse sand, Au- gust 1977; 1 female, 1 male, 1 juvenile, station 2748-06, 27°37.2’N, 83°53.5’W, 50 m, coarse sand, August 1977; 1 female with oostegites, 1 male, station 2748-06, 27°37.2’N, 83°53.5’W, 50 m, coarse sand Eebruary, 1978; 2 juveniles, station 2748-06, 27°37.2’N, 83°53.5’W, 50 m, coarse sand, November 1978; 1 female, station 2748-07, 27°37.2’N, 83°53.5’W, 50 m, coarse sand, August 1977; 1 male, station 2748-07, 27°37.2’N, 83°53.5’W, 50 m, coarse sand, Novem- ber 1977; 1 female, station 2748-09, 27°37.2’N, 83°53.5’W, 50 m, coarse sand, November 1977; 1 female with oosteg- ites, 2 males, station 2748-11, 27°37.2’N, 83°53.5’W, 50 m, coarse sand, November 1977; 1 ovigerous female, sta- tion 2851, 27°03’25.8”N, 83°0r08.5”W, 36 m, fine sand; 1 male, station 2856-E, 29°54’01.3”N, 87°24’00.2”W, 30 m, fine sand; 1 subadult male, station 2856-E, 29°54’01.3”N, 87°24’00.2”W, 30 m, fine sand, September 1977; 1 male, sta- Figure 3, Chelipeds of Alokolliopseudes mocsweenyi 'coastal morph' from Ft. Morgan, Alabama. A. Adult mole. B. Female with oostegites. Scale bar = 0.2 mm. 31 Drumm and Heard Figure 4 . Mop showing the distribution of Alokolliopseudes mocsweenyi. Block circles represent the 'offshore morph' ond tri- ongles indicote the 'coostol morph. ' tion 2856^H, 29°54’01.3”N, 87°24’00.2”W, 30 m, fine sand, September, 1977; 1 male, 1 juvenile, station 2856-J, 29°54’01.3”N, 87°24’00.2”W, 30 m, fine sand, September 1977. Geographic distribution: NW Atlantic (South Carolina to Florida Keys), eastern Gulf of Mexico (COM) (northward to coastal Mississippi), bathymetric range: 0.5-82 m (Figure 4). Remarks: The ‘offshore morph’ of A. macsweenyi can be distinguished from the ‘coastal morph’ most notably by dih ferences in the male cheliped. The propodus of the male cheliped for the ‘coastal morph’ (Figure 3A) is much more robust and is short (less than 2 times as long as broad, ex- eluding fixed finger), while the propodus of the ‘offshore morph’ is long (more than 2 times as long as broad) (Figure 2E). The dactylus cutting edge of the ‘coastal morph’ does not have a medial tooth as in adult males of the ‘offshore morph.’ The terminal claw of the fixed finger of the propo- dus in the ‘offshore morph’ can either be of regular size (Figure 2E) or reduced (Eigure 2E). Subadult males have a propodus shape similar to females (Eigure 2G). The females of both forms are nearly identical; however, the fixed finger cutting edge of the ‘coastal morph’ (Eigure 3B) has rarely been observed to possess a proximal tooth. This tooth can be large (Eigure 2A), or small (Eigure 2B) in the ‘offshore morph.’ However, several of the females exam- ined, especially ovigerous females, lacked this tooth (Eigure 2C). One ‘offshore morph’ female with oostegites had a small setose tooth on the dactylus cutting edge (Eigure 2D). Examination of material from the eastern GOM revealed the presence of a new ‘morph’ of Alokalliapseudes maeswee- nyi, which generally occurred in offshore sites and greater depths than the inshore ‘coastal morph’. The morphs can generally be distinguished by differences in the cheliped. MeSweeny (1968) in an unpublished MS thesis noticed that a small percentage of females of A. macsweenyi collected in the Biscayne Bay area of South Elorida had a small tooth proximally on the fixed finger cutting edge. However, the senior author has examined numerous specimens of the ‘coastal morph’ throughout its range and has never seen this tooth on the fixed finger. Since both forms of the female cheliped are apparently represented in offshore and coastal habitats, we are hesitant to call the ‘offshore morph’ a sepa- rate species (although one form is much more common in one region than the other, and vice versa). It is often diffF cult to quantify variation within a species, hence the reason many biologists are skeptical about the subspecies category. Whether one agrees with subspecies or full species status, it is clear that the ‘offshore morph’ is distinct enough to sug- gest specific separation from the ‘coastal morph.’ It would be interesting to determine whether these phenotypic diF ferences are associated with genetic isolation. This species might be diverging and undergoing incipient speciation. The present pattern suggests that selection is favoring one form over the other in different habitats. The pattern of the adult male cheliped of the ‘offshore morph’ could be at- tributed to paedomorphosis (the retention of juvenile chan acteristics in the adult) because the juvenile males of the ‘coastal morph’ have a slender cheliped propodus as seen in the adult males of the ‘offshore morph.’ This warrants further investigation. Genus Mesokalliapseudes Eang, 1956 Kalliapseudes (Mesokalliapseudes) Eang 1956: 216. Mesokalliapseudes: Gutu 2006: 142. 32 Tanaidacea from the Northwestern Atlantic Diagnosis (modified after Gutu 2006): Accessory flagel- lum of antennule with 3 or 4 articles. Antenna peduncle without double row of plumose setae on last article. Che- liped without exopodite; propodus slender and very long, much longer than carpus, fixed finger shorter than dactylus. Pereopod 1 without exopodite. Pereopods 2 and 3 dactylus with long and thin outer proximal digitiform prolongation, with few sensory setae. Pereopods 4 and 5 short and thick with some sensory setae; unguis absent. Pereopod 6 dacty- lus with subterminal seta. Pleopod exopodite biarticulate. Pleotelson with two terminal long plumose setae. Male with cheliped similar to female. Remarks: The distribution of this genus occurs exclusively in the New World. Four of the 6 species occur in the north- west Atlantic and the other 2 occur in the northeast Pacific (on the west coast of Baja California, Mexico). Mesokal- liapseudes is characterized from the other genera within the subfamily Kalliapseudinae by the following combination of characters: 1) last peduncle article of antenna lacking dou- ble-row of plumose setae, 2) male and female cheliped with very long and slender propodus and with an apparent lack of sexual dimorphism, and 3) absence of exopodites on the cheliped and first pereopod. Mesokalliapseudes bahamensis Sieg, 1982 (Figures 5, 14A, C, G, 1) Kalliapseudes (Mesokalliapseudes) bahamensis Sieg 1982: 3-10, figures 1-4; Bamber 1993: 122; Drumm 2003: 2, 11. Kalliapseudes bahamensis Bamber 1993: 128-130, figure 5. Mesokalliapseudes bahamensis Gutu 2006: 142, 148, 150, 151, figures 232-235. Type material: Holotype female (USNM 181707), paratypes (93 juveniles and 69 females, USNM 181901), paratypes (17 juveniles and 14 females, ZMK Tan. 40). Material examined: Paratypes (USNM 181901), San Salva- dor, Bahamas, inside NW reef, near Dump Reef, 24°08’N, 74°28’W 4 m, 18 December 1979; Kiawah Island, SC, 32°29’6”N, 78°49’18”W, S121, SERTC Invert. Collection, SCDNR, 52.0 m, coll. David Knott, 6 August 1981, 1 ovi- gerous female (dissected) ~ 6.5 mm, 3 females with emptied marsupium, 3 females with oostegites, 3 subadult females and 1 subadult male; offshore disposal area. Charleston, SC, 32°42’30”N, 79°5r36”W, S98, SERTC Invert. Col- lection, SCDNR, 8-17 m, coll. David Knott, August 1978, 1 subadult female; off Savannah River, GA, 31°44’6”N, 80M3’0.1”W, S116, SERTC Invert. Collection, SCDNR, 33 m, coll. David Knott, 21 August 1980, 1 female with emptied marsupium and 1 subadult male; off Tittle Tybee Island, GA, 3U4r6”N, 80°20’48”W, S119, SERTC Invert. Col- lection, SCDNR, 28 m, coll. David Knott, 10 March 1981, 1 subadult male; off Amelia Island, EE, 30°37’00.12”N, 8U10’41.8”W, S117, SERTC Invert. Collection, SCDNR, 22 m, coll. David Knott, 4 August 1980, 4 subadult males ~ 3.7 mm. 1 adult female; COM, 27°37’2”N, 83°53’5”W, Figure 6 . Map showing the distribution of Kalliapseudes baha- mensis. Block circles represent previously published records and triangles indicate new distribution locations. MAEEA, 50 m, 9 August 1977. Diagnosis: (Adult) Rostrum rounded. Pereonites with- out anterolateral apophyses. Pleotelson broader than long. Third peduncle article of antenna spinulate. Mandibular palp terminally with simple seta. Eixed finger of propodus of cheliped less than one half length of dactylus; cutting edge of dactylus with more than 10 long setae increasing in length distally. Type locality: San Salvador, Bahamas, inside NW reef, near Dump Reef, 24°08’N, 74°28’W (Eigure 6). Geographic distribution:. NW Atlantic and Gulf of Mexico, from South Carolina to southeast Elorida (new locality re- cords), San Salvador Bahamas, Caribbean Sea (Carrie Bow Cay, Belize) , bathymetric range: 4-52 m (Eigure 6). Remarks: Examination of material from the collections of SERTC confirmed the presence of M. bahamensis in the coastal and shelf waters off South Carolina, Georgia, and northeastern Elorida. Additional specimens of this species were also made available by Judy Johnson, Nova Southeast University, from shallow water collections made off Et. Eauderdale on the southeastern coast of Elorida. The only major difference found between the SE Elorida specimens and those from further north was the larger size of the for- mer (1 ovigerous female from South Carolina was 6.5 mm). Gutu (2006) reported this species off Carrie Bow Cay, Belize which extended its range into the northwestern Caribbean Sea. Examination of material from MAEEA also revealed the presence of M. bahamensis at a depth of 50 m, which extends its range into the COM. This species can be distinguished from its congeners by its distinct armature of the female cheliped (Eigure 5B) and the absence of anterolateral apophyses on the pereonites (Eigure 5A). Mesokalliapseudes brasiliensis (Bacescu, 1986) (Eigure 7) Drumm and Heard Kalliapseudes viridis brasiliensis: Bacescu 1986: 93, 95, 96, figure 2. Kalliapseudes (Mesokalliapseudes) viridis brasiliensis: Gutu 2006: 142. Mesokalliapseudes brasiliensis: Gutu 2006: 142; Drumm and Heard 2007: 459, 467. Type material:. Holotype female (MHN Grigore Antipa No. 695). Material examined: 7 adult males, 9 females with oostegites and 4 ovigerous females (MZUSP 16.899), Brazil, 23°36’S, 44°46’W, 48 m depth; 5 females with oostegites (1 partly dis- sected), 3 females with emptied marsupium, 5 adult males (1 partly dissected), Trinidad, sta. 5-1, coll. August 2003. Diagnosis: Rostrum round, tapering anteriorly. Pereonites lacking anterolateral apophyses. Pleotelson broader than long. Inner flagellum of antennule with three articles; first peduncle article about 3.3 times as long as broad. Third an tide of antenna without distinctive spinulate process. Ten minal spiniform seta of mandibular palp naked and stout, approximately seven times as long as broad. Fixed finger of the propodus of cheliped less than one half the length of dactylus. Gutting edge of the dactylus of cheliped with 3 or 4 setae midway and one distal seta near unguis. Pereopod 6 dactylus with one subterminal seta. Last article of uropod ex- opodite approximately 1.6 times as long as second article. Type locality: East of Port of Tubarao, Brazil, 20°15.5’S, 40°05.3’W, 29 m depth (Figure 8). Geographic distribution: SW Atlantic (Brazil) and NW An lantic (Trinidad), bathymetric range: 29-48 m (Figure 8). Remarks: Examination of new material extends the range of this species in the northwest Atlantic off Trinidad. Me- sokalliapseudes brasiliensis was originally considered a subspe- cies of M. viridis (Bacescu 1986); subsequently, Gutu (2006) considered it a valid species based on the different geograph- ical distributions of the species but recognized the very scant original description. Bacescu (1986) described this species as lacking lateral plumose setae on the pleonites, but Gutu (pers. comm., Bucharest “Grigore Antipa” Natural History Museum, Romania) examined the type material and com firmed the presence of plumose setae. Gutu (pers. comm.) compared the type specimen to our illustrations and noted only 2 differences: 1) the number of ventral spiniform setae on the pereopod 1 propodus (3 in our specimen and 2 in the type specimen) and 2) the number of spiniform setae on the pereopod 6 dactylus (2 or 3 in our specimens and 4 in the type specimen). These characters have been shown to vary within species (one ovigerous female we examined had 4 spiniform setae on the pereopod 6 propodus) so they should not be used to diagnose species. One of the most iim portant characters for distinguishing species of Mesokalliap- seudes is the nature of the cheliped (i.e, setation/spination on the cutting edges and the proportion of dactylus/ pro- dus fixed finger length). The specimens we examined have 3 or 4 setae midway on the cutting edge of the dactylus and one seta distally near the unguis (Figure 7G). Gutu (pers. comm.) examined the type specimen cheliped and did not notice any setae on the cutting edge, but mentioned that this could be due to poor preservation. We have decided to treat this species as conspecific with M. cf. brasiliensis sensu stricto rather than give it designation as a new species until further material (topotypic) can be examined. Mesokalliapseudes soniadawnae Bamber, 1993 (Figure 14F) Kalliapseudes (Mesokalliapseudes) soniadawnae Bamber 1993: 122, figures 1-4; Drumm 2003: 2, 11; Gutu 2006: 141. Kalliapseudes soniadawnae: Bamber 1993: 128, 129, 130. Mesokalliapseudes soniadawnae: Gutu 2006: 142, 151. Type material: Holotype female (NMW.Z. 1991.099.1), 1 paratype male (NMW.Z.1991.099.2). Material examined: None available for study. Diagnosis (from Bamber 1993): Rostrum rounded. Ante- rolateral apophyses on pereonites 2-6. Pleotelson broader than long. Inner flagellum of antennule with three articles. Third peduncle article of antenna not spinulate. Mandibu' lar palp terminally with long seta. Fixed finger of propodus of cheliped less than one half length of dactylus. Type locality: Garibbean Sea, Trinidad, 10°40’N, 61°35 W, depth 10 m. Geographic distribution: Known only from the type locality. 34 Tanaidacea from the Northwestern Atlantic A'"" - '"n V, - I 0 - OcC'ifn 1 E ) f j ! j ( 1 type locality Figure 8. Map showing the distribution of Mesokolliapseudes cf. brasiliensis. The black circle represents the previously published record and triangles indicate new distribution locations. Remarks: Attempts to borrow type material from the Na- tional Museum of Wales were unsuccessful. Based on Bam- ber’s (1993) description, this species can be distinguished from the other congeners by the following characters: 1) a short stout pectinate spiniform seta on the ventrodistal cor- ner of the pereopod 1 basis, and 2) no spinulate process on the second peduncular article of the antenna. Mesokalliapseudes thalasispeleus Gutu, 2006 (Figures 14H, J) Mesokalliapseudes thalasispeleus Gutu 2006: 142-151, fig- ures 209-231. Type material: Holotype female with oostegites no. 250.299, 1 allotype male no. 250.300, MHN Grigore Antipa. Material examined: None available for study. Diagnosis (from Gutu 2006): Rostrum rounded. Pere- onites lacking anterolateral apophyses. Pleotelson as long as broad. Inner flagellum of antennule with three articles. Third peduncle article of antenna not spinulate. Mandibu- lar palp terminally with short spiniform seta. Fixed finger of propodus of cheliped less than one half the length of dactylus. Female cheliped with less than 10 short spiniform setae on dactylus cutting edge. Type locality: NW Atlantic, Exuma Gays, Bahamas, ap- proximate coordinates: 23°32’N, 75°50’W (exact coordi- nates unknown). Geographic distribution: Known only from the type locality. Remarks: Mesokalliapseudes thalasispeleus is the second known species of Mesokalliapseudes identified from the Ba- hamas, the other one being M. bahamensis and can be dis- tinguished from it and the other congeners by two major characters: 1) the shape of the pleotelson (as long as broad; all other species are broader than long), and 2) the short spiniform seta on the mandibular palp terminus. Mesokal- liapseudes thalasispeleus appears to be unique in having lon- ger than usual simple setae on the anterior and posterior corners of the pereonites (approximately as long as the as- sociated pereonite). Subfamily Tanapseudinae Bacescu, 1978 Genus Psammokalliapseudes Lang, 1956 Diagnosis: Antennule inner flagellum not reduced. Ghe- liped and pereopod 1 with exopodite. Psammokalliapseudes granulosus Brum, 1973 (Figures 9, 13E) Psammokalliapseudes granulosus Brum 1973: 2-3, figure 2; 1974: 4-7, figures 8-26; Bacescu 1979: 3; Bacescu and Absalao 1985: 53. Cirratodactylus floridensis Gardiner 1973: 237, figures 1-6; Bacescu and Absalao 1985: 53; Sieg 1986: 22; Gutu 1996: 70. Type material:. None apparently by original designation. Material examined: 3 subadult males (USNM 1011363), ~ 2.9 mm, Et. Lauderdale, EL, 25°59’14”N, 80°05’25”W, 20 m depth, coll. June 1992, det. David Drumm; 1 female with oostegites (USNM 141481), North Miami, EL, 25°54.7’N, 80°06’W, 15 m depth, sand, coll. May 1964; 2 spec., MA- ELA station 2103, 26°25’N, 83^57 W, 33 m, fine sand, coll. 1976, det. Heard and Sieg 1983; 4 spec., MAELA station 2104, 26°25’N, 83°23’W, 53 m, coarse sand, coll. 1975, det. Heard and Sieg 1983; 2 spec., MAELA station 2211, 27°56’N, 83°52’W, 43 m, coarse sand, coll. 1975, det. Sieg and Heard 1983; 2 spec., MAELA station 2315, 28"33’N, 84°20’W, 38 m, silty fine sand, coll. 1975, det. Heard and Sieg 1983; 3 spec., MAELA station 2317, 28°56’N, 84°05’W, 29 m, silty, very fine sand, coll. 1975, det. Heard and Sieg 1983; 2 spec., MAELA station 2422, 29°30’N, 84°27 W, 24 m, medium fine sand, coll. 1976, det. Heard and Sieg 1983; 2 spec., MAELA station 2424, 29°13’N, 85°00’W, 27 m, me- dium sand, coll. 1975, det. Heard and Sieg 1983; 23 spec., MAFLA station 2425, 29°05’N, 85°15’W, 36 m, medium sand, coll. 1975, det. Heard and Sieg 1983; 3 spec., MAFLA station 2426, 28°57’N, 85°23’W, 82 m, fine sand, coll. 1977, det. Heard and Sieg 1983; 3 spec., MAELA station 2528, 29°54’N, 86°04’W, 37 m, coarse sand, coll. 1975, det. Heard and Sieg 1983; 3 spec., MAELA station 2529, 29°55’N, 86°06’W, 38 m, coarse sand, coll. 1975, det. Heard and Sieg 1983; 10 spec., MAELA station 2530, 29°51’N, 86°06’W, 41 m, medium sand, coll. 1976, det. Heard and Sieg 1983; 2 spec., MAELAstation 2532, 29°46’N, 86M2’W, 45 m, coarse sand, coll. 1975, det. Heard and Sieg 1983; 2 spec., MAELA station 2748, 27°37’N, 83°53’W, 50 m, coarse sand, coll. 1976, det. Heard and Sieg 1983; 2 spec., MAELA station 2853, 29°18’N, 84°19’W, 29 m, coarse sand, coll. 1977, det. Heard and Sieg 1983; ~35 specimens (adult males, females, juveniles, mancas), Culebra Island, Puerto Rico, 28 m, coll. 2003; 1 adult female. Lover’s Beach, northeastern edge of Man-O-War Bay, Tobago, 1U18’15”N, 60°31’25”W, April 35 Drumm and Heard Figure 9 . Psommokalliopseudes granulosus from Puerto Rico. A. Dorsal view of body of adult female with oostegites. Scale bar = i .0 mm. B. Lateral view of adult mole. Scale bar = 1.0 mm. C. Pereopod 5 of adult female. Scale bar = 0.2 mm. 1992, coll. (Sc id. Richard Heard, 2 m depth, coral sand/ rubble. Diagnosis (adult): Rostrum rounded. Pleotelson broader than long. Antennule inner flagellum with t\^^o articles. Pe- reopod 1 dactylus with three ventral teeth associated with a short spinule. Dactylus of pereopods 1-6 with distal re- curved sensory setae. Type locality: Ponta dos Calderos e a llha Redonda, Brazil (Figure 10). Geographic Distribution: Brazil, Caribbean Sea (Puerto Rico, Tobago), NW Atlantic (South Florida), eastern COM, bathymetric range: 20-82 m (Figure 10). Remarks: Psammokalliapseudes granulosus, originally de- scribed from Brazil, was reported as a new genus and species, Cirratodactylus floridensis by Gardiner (1973) a few months later from South Florida waters. Gardiner (1973) further designated a new monotypic family Cirratodactylidae Gan diner, 1973 to accommodate it. Bacescu and Absalao (1985) synonymized C. floridensis with P. granulosus, relegating the genus Cirratodactylus and family Cirratodactylidae to junior synonyms of Psammokalliapseudes Lang, 1956 and Kalliap- seudidae, respectively. Examination of new material and MAFLA material ex- tends this species range into the Caribbean Sea (Puerto Rico and Tobago) and the eastern GOM and its depth range is extended to 82 m. This species can easily be distinguished from its only other congener P. mirabilis and is unique among tanaidaceans in having curled sensory setae on the dactylus of all of the pereopods (Figure 9C). Examination of mancas (postembryological instars with incompletely deveh oped postcephalic appendages) revealed the presence of ex- opodites on the last tw^o pereopods. This represents the first record of this occurring in the genus Psammokalliapseudes. Genus Tanapseudes Bacescu, 1978 Diagnosis: Antennule inner flagellum reduced. Cheliped and pereopod 1 lacking exopodite. Tanapseudes gutui Hansknecht, Heard and Bamber, 2002 (Figures 11, 13F, G). Tanapseudes gutui Hansknecht et al. 2002: 67, figures 1-2. Type material: Holotype: adult male (USNM 1001787). Paratypes: 2 males, 1 ovigerous female (USNM 1001788); 1 male, 1 ovigerous female (GCRL 2038); 1 male (MHN Grigore Antipa No. 250.181); 2 ovigerous females (MHN Grigore Antipa No. 250.180); 1 male (NHM 2001.6903); 1 female (NHM 2001.6904). Material examined: Paratypes: 1 ovigerous female, 1 adult male, GCRL 2038, CH2MHill Consultants, Caro- lina WWTP, Puerto Rico, San Juan Estuary, 18°27.80’N, 65°53.44’W, St. Cl-2, 34 m, sandy clay, 30 October 1999. Non-types: 1 adult male, EPA Coastal 2000, 6701, St. PR44, Puerto Rico, id. Tom Hansknecht; 3 males, 1 female and 2 juveniles, MAEEA station 2426, 28°57’N, 85°23’W, 82 m, fine sand, coll. 1977. Diagnosis: Pleonites with only few (3 at most) lateral plu' mose setae. Pleotelson with very pronounced rounded posterF or protuberance. Male pereopod 1 with dorsodistal spiniform '(V\ ■ H . * * X ^ .'if/ititric Ocei//t 4 - , • type locality Figure 10 . Mop showing the distribution of Psommokolliop- seudes granulosus. Block circles represent previously published records and triangles indicate new distribution locations. 36 Tanaidacea from the Northwestern Atlantic Figure 1 1 . Tonopseudes gutui, adult male. A. Dorsal view of body. Scale bar = 0.3 mm. B. Uropod. Scale bar = 0.05 mm. C. Cheliped. Scale bar = 0.01 mm. D. Pleotelson. Scale bar = 0. 1 mm. seta on propodus reduced or lacking. Male cheliped carpus with ventrodistal rounded protuberance. Pereopods 2-5 with ventral margins of merits and carpus heavily setose. Uropod basal article lacking inner distal spiniform projection. Type locality: San Juan, Puerto Rico, 18°27.80’N, 65°53.44’W, 3-34 m depth (Figure 12). Geographic distribution: Caribbean Sea (Puerto Rico, To- bago) and eastern COM, bathymetric range: 3-82 m depth (Figure 12). Remarks: Examination of MAFLA material extends this spe- cies range into the eastern COM and its depth range is ex- tended to 82 m. Hansknecht et al. (2002) described and illus- trated the uropod exopodite of T. gutui as being biarticulate. However, examination of type material revealed the presence of 3 articles (1 small round basal article. Figure IIB). They also mention that the adult male cheliped has a tooth midway on the cutting edge of the dactylus; we did not see this tooth on the paratype male we examined (Figure IIC). Tanapseudes gutui can be distinguished from the other congeners by the male pereopod 1 propodus, which has a reduced dorsodistal spiniform seta and the male cheliped, which has a carpal process (Figure IIC). Gutu and Angsu- panich (2005) describe this pattern in specimens collected from the Andaman Sea in Thailand which they attribute to T. ormuzana. Their specimens likely represent a new species because these characteristics were not evident in the material examined by us, Hansknecht et al. (2002) or in the original description (Bacescu 1978). The location of their material (Thailand) is also distant from the type locality (Puerto Rico). The posterior protuberance of the pleotelson (Figure HD) of T. gutui also seems to be more pronounced and pereopods 2-5 more setose than in the other species. Key to genera and species of Kalliapseudidae presently known in the northwest Atlantic 1. Mandibular palp uniarticulate and short, with one terminal seta (Figure 13 A) 2 Mandibular palp uniarticulate and long, with a row of long, plumose setae (Figure 13B) 3 2. Pereopods with dactylus having curled sensory setae at tip (Figure 9C); antennule with inner flagellum biarticulate (Figure 13E) Psammokalliapseudes granulosus Brum, 197 3 Pereopods with dactylus lacking curled sensory setae at tip (Eigures 13 C, G); antennule with inner flagellum vestigial, uniarticulate (Eigure 13 E) ... Tanapseudes gutui Hansknecht, Heard and Bamber, 2002 3. Chelipeds not sexually dimorphic; antenna with third peduncle article lacking large triangular tooth (Eigure 14C) Chelipeds showing strong to moderate sexual dimorphism; antenna with third peduncle article having large triangular tooth (Eigure 14D) Alokalliapseudes macs weeny i (Drumm, 2003) 4. Pereonites lacking apophyses (Eigure 14E) 5 Pereonites 2-4 with anterolateral apophyses (Eigure 14E) Mesokalliapseudes soniadawnae Bamber, 1993 5. Mandibular palp armed distally with single spiniform seta (more than 6 times as long as broad) spiniform seta (Eigure 7B) Mesokalliapseudes brasiliensis (Bacescu, 1986) Mandibular palp armed distally with either a single long seta or a single short spiniform seta (less than 6 times as long as broad) spiniform seta 6 6. Pleotelson broader than long (Eigure 14G); mandibular palp armed distally with a long simple seta (Eigure 141) Mesokalliapseudes bahamensis Sieg, 1982 Pleotelson as broad as long (Eigure 14H); mandibular palp armed distally with a short spiniform seta (Eigure 14J) Mesokalliapseudes thalasispeleus Gutu, 2006 A . iJ/itii/ir Oiva/i ^ type locality • Figure 12. Map showing the distribution of Tonopseudes gutui. Block circles represent previously published records and the tri- angle indicates o new distribution location. 37 Drumm and Heard Figure 13 . Plate I for the illustrated key to the NW Atlantic kalliopseudids. A. Tanapseudes ormuzano, left mandible. Scale bar = 0.03 mm. B. Kolliopseudes mognus, left mandible. Scale bar = 0. 1 mm. C. T. ormuzano, distal end of pereopod I . Scale bar = 0.05 mm. D. Kolliopseudes mouritonicus, distal end of pereopod 1 . Scale bar = 0. 1 mm. E. Psommokolliopseudes granulosus, ontennule. Scale bar = 0. 1 mm. F. Tanapseudes gutui, ontennule. Scale bar = 0.05 mm. C. T. gutui, pereopod 3. Scale bar = 0.05 m. Family Characteristics The family Kalliapseudidae is currently defined by the combination of the absence of a palp on the maxillule and the presence of sensory setae on the dactylus of the pereo- pods. The presence of exopods on pereopods 4 and 5 of the manca (one or more postembryological instars with incoim pletely developed postcephalic appendages) might be anotlv er synapomorphy of the family. The senior author recently confirmed the presence of this character in a species of mikalliapseudes, constituting the first report of this occurring in the Hemikalliapseudinae. The only exception is the re- port of the apparent lack of exopodites for the manca stage of Psammokalliapseudes mirabilis (Lang 1956). Lang’s (1956) observations need further confirmation, since exopods have been reported for all other known mancas for the 3 sub- families. The only other group of tanaidaceans reported to exhibit this character are members of the sphyrapoid sub- family Pseudosphyrapodinae Gutu, 1980 (see Gutu 2006), a mostly deep-water group with apseudid affinities and not closely related to the Kalliapseudidae. For undetermined reasons, the presence of exopods appear to have been inde- pendently retained within these 2 disparate groups. The sensory setae on the dactylus of the pereopods is a very confusing character and we do not think it should be included in the family’s diagnosis or in phylogenetic studies. It is only through theories of homology that phylogenetic analysis can proceed. Position (similarity of topographical relationships) is one key assumption of homology. Some ka- lliapseudids have terminal sensory setae and some have sub- terminal setae. The structures the setae are attached to are likewise suspect. Members of the Kalliapseudinae definitely have a unique structure: numerous setae attached to a short and thick dactylus. The lack of positional and structural similarities across the subfamilies violates the assumption of homology. The presence of sensory setae on the dactylus of the pereopods is found in the parapseudid genus ThaP cungella (Gutu and Angsupanich 2004) and resembles the setae found in some species of the kalliapseudid subfamily Hemikalliapseudinae, so this character should be used with caution. Ecology Little is known of the biology and ecology of most mem- bers of Kalliapseudidae. The feeding behavior of two spe- 38 Tanaidacea from the Northwestern Atlantic Figure 14, Plate 2 for the illustrated key to the NW Atlantic kalliapseudids. A. Mesokolliopseudes bohomensis, female cheliped. Scale bar = 0. 1 mm. B. Alokolliopseudes mocsweenyi, female cheliped. Scale bar = 0.2 mm. C. A^. bohomensis, antenna peduncle. Scale bar = 0.05 mm. D. A. mocsweenyi, antenna peduncle. Scale bar = 0.05 mm. E. A. macsweenyi, pereonites. Scale bar = 0.5 mm. F. Mesokolliopseudes soniodownoe, pereonites modified after Bomber (1993). Scale bar = 0.5 mm. G. A/I. bohomensis, pleotelson. Scale bar = 0.2 mm. H. Mesokolliopseudes tholasispeleus, pleotelson modified after Gutu (2006). Scale bar = 0.2 mm. I. M. bahamensis, right mandible. Scoel bar = 0. 1 mm. J. M. tholasispeleus, left mandible modified after Gutu (2006). Scale bar = 0. 1 mm. cies [R granulosus (subfamily Tanapseudinae) and A. macswee- nyi (subfamily Kalliaseudinae)], which distincdy differ in moudipart morphology, was described by Drumm (2005). Based on the observations of Drumm (2005), A. macsweenyi constructs “tubes” in soft sediments using mucus secretions and feeds by filtering detritus and diatoms with plumose setae attached to the chelipeds and maxillipeds. In contrast R granulosus, which lacks a permanent domicile, appears to be fossorial and feeds by scraping the organic material (e.g. microflora) off sand particles (Drumm 2005). Although a vast majority of the species within the sub- order Apseudomorpha are fossorial, (e.g., Apseudidae, Sphyrapidae) or epibenthic (e.g., some Pagurapseudidae and Metapseudidae), some members of the families Kah liapseudidae, Parapseudidae Gutu, 1981, and possibly the small and poorly known Numbakullidae Gutu and Heard, 2002 appear to occupy permanent or semipermanent tubes or burrow domiciles. Members of the parapseudid genera Discapseudes Bacescu and Gutu, 1975 and Halmyrapseudes Bacescu and Gutu, 1974 construct well -developed tubes (Bacescu and Gutu 1974, 1975, R. Heard, pers. obser.). However, there can be different interpretations of whether or not members of the subfamily Kalliapseudinae are tube or burrow dwellers, or both. Based on the authors’ person- al observations and those of Drumm (2005), we consider A. macsweenyi to be a tube dweller sensu law. When the sediments surrounding its vertically oriented domicile are flushed away, a soft mucus “tube” remains; however, it may be a matter of semantics whether this constitutes a true tube or a mucus burrow-lining that remains intact. Members of 39 Drumm and Heard the Kalliapseudinae appear to be suspension or filter feed- ers occupying permanent domiciles in soft-bottom substrata (e.g., sand, sand-silt, mud). In contrast, members of the sub- families Hemikalliapseudinae and Tanapseudinae, which are also known from soft-bottom habitats, appear to be fos- sorial deposit feeders that lack permanent domiciles. Acknowledgements We would like to thank R. King and D. Knott (South Carolina Department of Natural Sciences) and J. Johnson (Nova Southeastern University) for providing specimens of M. bahamensis. Drs. R. Bamber and M. Gutu provided helpful discussions on kalliapseudid systematics. Dr. K. Christol dos Santos (Universidade de Sao Paulo) loaned specimens of M. brasiliensis and T. Hansknecht (Barry A. Vittor & Associates) pro- vided specimens of T. gutui and M. brasiliensis for study. We thank J. Shaw and C. Schloss (GCRL Gunter Library) for procuring interlibrary loan material. Roger Bamber and R. King provided valuable editorial insights and suggestions on an earlier version of this manuscript that greatly improved the quality of the final work. This research was supported by NSF grant DEB-0529749. Literature Cited Anderson, G. 2009. Tanaidacea classification. http://peracarida. usm.edu/TanaidaceaTaxa.pdf (viewed on 7/20/2009). Bacescu, M. 1978. Contribution to the knowledge of Monokono' phora (Crustacea: Tanaidacea) from the NW of the Indian Ocean. Memoriile Sectiilor Stiintifice, Edit. Academiei Repu- blicii Socialiste Romania, Seria IV, Tomul 1:197-220. Bacescu, M. 1979. Kalliapseudes gianucai, a new Tanaidacea from the Brazilian waters. Revue Roumaine de Biologie (Serie de Biolo- gie Animale) 24:3-8. Bacescu, M. 1986. Heteromysis mureseanui n. sp. and Kalliapseudes viridis, ssp. brasiliensis n. ssp., from the Brazilian littoral wa' ters. Revue Roumaine de Biologie, Serie de Biologie Animale 31:93-97. Bacescu, M. and R.S. Absalao. 1985. Hemikalliapseudes cavooreni n. sp. and a few remarks on the Brazilian Apseudoidea. Travaux du Museum d’Histoire Naturelle “Grigore Aitipa” 27: 49-54. Bacescu, M. and M. Gutu. 1974. Halmyrapseudes cubanensis n. g. n. sp. and H. bahamensis n. sp., brackishwater species of Tanaida' cea (Crustacea). Travaux du Museum d’Histoire Naturelle “Gri- goreAntipa” 15:91-101. Bacescu, M. and M. Gutu. 1975. A new genus (Discapseudes n. g.) and three new species of Apseudidae (Crustacea, Tanaidacea) from the northeastern coast of South America. Zoologische Mededelingen 49:95-113. Bamber, R.N. 1993. A new species of Kalliapseudes (Crustacea: Ta' naidacea: Kalliapseudidae) from Trinidad. Proceedings of tbe Biological Society of Washington 106:122-130. Brum, S.l.N. da. 1973. Contribucao ao conhecimento da fauna do Arquipelago de Abrolhos, Babia, Brasil, No. 4. Crustacea - Tanaidacea. Boletim do Museu de Historia Natural UFMG Zoologia 18:1-5. Brum, S.l.N. da. 1974. Contribucao ao conhecimento da fauna do Arquipelago de Abrolhos, Bahia, Brasil, No. 5. Crustacea - Tanaidacea. Boletim do Museu de Historia Natural UFMG Zoologia 20:1-15. Drumm, D.T 2003. Kalliapseudes (Mesokalliapseudes) macsweenyi, a new species of Kalliapseudidae (Crustacea: Tanaidacea: Apsem domorpha) from mangroves in Florida. Zootaxa 357:1-12. Drumm, D.T. 2004. Comparative morphology of the mouthparts, chelipeds and foregut of two kalliapseudid tanaidaceans (Crus- tacea: Apseudomorpha). Proceedings of the Academy of NatU' ral Sciences in Philadelphia 154:137-147. Drumm, D.T. 2005. Comparison of feeding mechanisms, respira' tion, and cleaning behavior in two kalliapseudids, Kalliapseudes macsweenyi and Psammokalliapseudes granulosus (Peracarida: Ta- naidacea). Journal of Crustacean Biology 25: 203-211. Drumm, D. and R. Heard. 2007. Redescription of Mesokalliapseudes crassus (Menzies, 1953) (Crustacea: Tanaidacea: Kalliapseudi' dae): the first record of a hermaphroditic kalliapseudid. Proceed- ings of the Biological Society of Washington 120:459-468. Drumm, D., R. Heard, and K. Larsen. 2009. Tanaidacea Web Site. http://www.usm.edu/gcrl/tanaids/ (viewed on 8/29/2009) Gardiner, L.F. 1973. A new species and genus of a new monokono- pboran family (Crustacea: Tanaidacea), from southeastern Flor- ida. Journal of Zoology, London 169:237-253. Gutu, M. 1980. Pseudosphyrapus, a new genus of a new fam- ily (Sphyrapidae) of Monokonophora (Crustacea, Tanaidaca). Travaux du Museum d’Histoire Naturelle “Grigore Antipa” 36:393-400. Gutu, M. 1981. A new contribution to the systematic and phylog- eny of the suborder Monokonophora (Crustacea, Tanaidacea). Travaux du Museum d’Histoire Naturelle “Grigore Antipa” 23:81-108. Gutu, M. 1996. Tanaidaceans (Crustacea, Peracarida) from Bra- zil, with descriptions of new taxa and systematical remarks on some families. Travaux du Museum d’Histoire Naturelle “Grig- ore Antipa” 36:23-133. Gutu, M. 2006. New Apseudomorpb taxa (Crustacea, Tanaidacea) of the world ocean. Curtea Veche, Bucharest, Romania, 318 p. Gutu, M. and S. Angsupanich. 2004. Description of two new gen- era and species of Tanaidacea (Crustacea) from shallow waters of the Andaman Sea, Thailand. Travaux du Museum National d’Histoire naturelle “Grigore Antipa,” 46:29-44. 40 Tanaidacea from the Northwestern Atlantic Gutu, M. and S. Angsupanich. 2005. Contribution to the knowl- edge of the kalliapseudids (Crustacea: Tanaidacea) from the Thai waters. Travaux du Museum National d’Histoire naturelle “Grigore Antipa,” 48:43-56. Gutu, M. and R.W. Heard. 2002. A new genus and species of a new family of apseudomorph tanaidaceans (Crustacea: Peracarida) from Australian waters. Travaux du Museum d’Histoire Natu- relle “Grigore Antipa” 44:93-103. Hansknecht, T, R.W. Heard, and R.N. Bamber. 2002. Tanapseudes gutui, a new species of apseudomorphan Tanaidacea (Crusta- cea: Peracarida) from the Caribbean Sea and the taxonomic status of the family Tanapseudidae Bacescu, 1978. Gulf and Caribbean Research 14:67-74. Lang, K. 1956. Kalliapseudidae, a new family of Tanaidacea. In: K.R Wingstrand, ed. Bertil Hanstrom. Zoological papers in honour of his sixty-fifth birthday November 20*, 1956. Zoo- logical Institute, Lund, Sweden, p. 313. Larsen, K. 2003. Proposed new standardized terminology for tanaid- acean Crustacea. Journal of Crustacean Biology 23:644-661. McSweeny, E.S. 1968. A systematic study of five species of Tanaida- cea (Crustacea: Malacostraca) collected in Southern Florida. M.S. Thesis, University of Miami, Miami, FL, USA, 172 p. Sieg, ]. 1980. Sind die Dikonophora eine polyphyletische Gruppe” Zoologische Anzeiger 205: 401-416. Sieg, J. 1982. Anmerkungen zum Genus Kalliapseudes Stebbing, 1910, mit Beschreibung einer neuen Art Kalliapseudes bahamen.' sis n. sp. (Crustacea: Tanaidacea). Mitteilungen aus dem Zoolo- gischen museum der Universitat Kiel 1:3-17. Sieg, J. 1986. Tanaidacea (Crustacea) von der Antarktis und Sub- antarktis. 11. Tanaidacea gesammelt von Dr. J.W. Wagele wahrend der Deutschen Antarktis Expedition 1983. Mittei- lungen aus der Zoologischen Museum der Universitat Kiel 2:1-80. 41 Gulf and Caribbean Research Volume 22 Issue 1 2010 Observations of a Black Grouper (Mycteroperca bonaci) Spawning Aggregation in Bermuda Brian E. Luckhurst Department of Environmental Protection, Bermuda, brian.luckhurst^gmail.coni DOI; 10.18785/gcr.2201.05 Follow this and additional works at: http:/ / aquila.usm.edu/ gcr & Part of the Marine Biology Commons Recommended Citation Luckhurst; B. E. 2010. Observations of a Black Grouper (Mycteroperca bonaci) Spawning Aggregation in Bermuda. Gulf and Caribbean Research 22 (l): 43-49. Retrieved from http://aquila.usm.edu/ gcr/vol22/ issl/5 This Article is brought to you for free and open access by The Aquila Digital Community. It has been accepted for inclusion in Gulf and Caribbean Research by an authorized editor of The Aquila Digital Community. For more information, please contact Joshua.Cromwell^usm.edu. Gulf and Caribbean Research Vol 22, 43-49, 2010 Manuscript received November 16, 2009; accepted February 9, 2010 OBSERVATIONS OF A BLACK GROUPER (NiYCTBROPBRCA BONACI) SPAWNING AGGREGATION IN BERMUDA Brian E. Luckhurst^ Marine Resources Division, Department of Environmental Protection P.O. Box CR 52, Crawl CRBX, Bermuda, ^Current address: 2-4 Via della Chiesa, 05020 Acqualoreto, Umbria, Italy, e-nuxil: brianduckhurst@gmail.com Abstract: Diving observations at a black grouper {Mycteroperco bonaci] spawning aggregation site on Bermuda's reef platform revealed many similarities to observations of this species obtained at multi-species spawning aggregation sites in Belize. In addition to similarities in body sizes, color patterns and some behavior, the principal spawning period in the days after the full moon was also similar. Although spawning was not observed in this study, there was ample indirect evidence of spawning at the site, i.e. courtship behavior by males, females with distended abdomens, and color changes. The formation of temporary spawning territories by males and courtship behavior within these territories is described and illustrated. Taken together, these data appear to indicate that the behavior of black grouper at spawning aggregations is consistent across a broad latitudinal range from Belize in the south to the northern limit of the species' range in Bermuda. Introduction Relatively few studies have been published on the bioh ogy of black grouper (Mycteroperca bonaci), and most of these studies have concentrated on the reproductive biology of this protogynous hermaphroditic species (Crabtree and Bullock 1998, Garcia-Cagide et al. 2001, Brule et al 2003, Teixeira et al. 2004). Spawning seasonality of black grouper at spawn- ing aggregation sites in Cuba has been described by Claro and Lindeman (2003). Although the black grouper is rec- ognized as a transient aggregation spawner (Domeier and Colin 1997), only a small number of studies have described the behavior of this species at fish spawning aggregation sites (FSAS) with the majority of the research being conducted in Belize (Heyman and Kjerve 2008, Paz and Sedberry 2008). One study in Florida (Eklund et al. 2000) examined an ag- gregation site in relation to a Marine Protected Area (MPA) boundary but provided less behavioral information as spawn- ing was not observed. Whaylen et al. (2004) reported see- ing small groups of black grouper with distended abdomens during observations at a primary Nassau grouper (Epineph- elus striatus) spawning aggregation site in Little Cayman but spawning was not observed. Black grouper have been an important species to the Ber- muda fishery for decades but suffered a significant decline in landings from the mid - 1970s along with many other grouper species (Luckhurst 1996). Although it was known that black grouper aggregated to spawn, the location of spawning sites was apparently not well known in the local fishing industry. In contrast, red hind (Epinephelus guttatus) spawning aggrega- tion sites were well-known and heavily fished, which prompt- ed early management action to seasonally protect these sites (Luckhurst 1998, Luckhurst and Trott 2009). In the summer of 2003, the location of a spawning aggregation site for black grouper was revealed by fishermen and this lead to research to define the dynamics of the aggregation. It was determined that the black grouper site was relatively close to an exist- ing red hind site which was seasonally closed to all fishing. Anecdotal evidence indicated that the black grouper site was being heavily fished and that the bag limit of one fish per boat per day was being routinely exceeded. As enforcement of the bag limit was problematic due to the large number of landing sites, it was decided to incorporate the black grouper site into a redefined and enlarged seasonally protected area (Fisheries Protected Areas Order 2004) which included the original red hind spawning aggregation site (Luckhurst, pers. obs.). Only after the site was seasonally closed to fishing was it possible to conduct an intensive research program to study the aggregation and learn more about its dynamics without interaction with fishermen at the site. The data presented here are the first to be derived from this ongoing study. Materials and Methods A week before diving observations began, 2 mooring buoys were placed about 40 m apart near the presumed cen- ter of the spawning aggregation site at a depth of about 30 m. This was done to avoid anchoring on the site which could have disturbed the aggregated fish and also increased the ef- ficiency of boat operations. There were 2 dive boats on the site for 3 days of the project with a single boat on the remain- ing 2 days. Diving observations commenced on the day of the full moon in June 2005 and continued for 6 consecutive days. No diving was possible on the fifth day due to rough sea conditions at the site. Teams of divers from each boat (2-4 divers per team) recorded their observations on waterproof paper on slates and all of the daily observations made dur- ing the study were collated and used for the present analysis. Divers surveyed the area widely and made estimate counts of the number of fish within their view and also estimated fish sizes. In addition, divers made notes on behavior and color patterns. After each dive, team members discussed Luckhurst TABLE I. Summary of doily observations at o block grouper spawning aggregation site in Bermuda in June and August 2005. No observations were mode in July. See Figure 3 for further details of the behavior noted on June 26 and August 25. Sunset was at 2030 hrs during the June observation period and at 1 954 hrs during the August period. Date 2005 Time (h) Moon phase Fish abundance Size-FL cm Observations estimate Mean (range) June 21 1300 Full 20+ 125 (110-150) Fish hovering mainly over sand holes 1500 25-30 125 (110-150) Few color changes but no interactions between fish 1700 30+ 110(90-150) Cone-shaped school of 30+ fish hovering above substrate, inactive; pole-body phase fish increasing in number June 22 1300 Full+l 70-100 No size estimates Single layer school moving over substrate, available several females with distended abdomens 1700 200-400 110(80-150) Bond of fish hovering 7-9 m above reef (10-15 fish high) - 2-4 % of fish in pole- body phase June 23 1730 Full+2 100-200 110(100-150) 70-80 % pole-phase fish, bond of fish hovering 3-5 m above reef June 24 1500 Full+3 150-200 100 (90-150) Bond of fish hovering 7-9 m above reef, % of females appears to hove increased from June 23 1815 150+ 90 (80-130) Increased % of females, minimum of 5-6 females with distended abdomens; mole courtship observed June 25 Full+4 No diving - rough sea conditions June 26 1645 Full+5 150+ 90 (80-140) Moles with pole sub-coudol fin margins, females with distended abdomens common, females comprise 90% of fish present, fish becoming more active 1855 250-300 90 (80-140) Moles (125-140 cm FL) in "sunburst" coloration set up temporary spawning territories, periodically swim 9-12 m. up into water column in courtship behavior, no interaction with females 1910 250-300 90 (80-150) Minimum of 12 contiguous spawning territories established, occupied by largest moles, oil in "sunburst" coloration exhibiting courtship behavior; dork-phose females appear to be sheltering in reef substrate 1925 Fish were becoming more active at the time that observations ceased August 24 1300 Full+5 125-150 100 (90-140) Fish formed cone-shaped school and hovered over reef, 1 0% pole-phase fish 1600 150-175 90 (80-140) Increase in school size, school moving between sand and reef, with associated color changes which were frequent and rapid August 25 1900 Full+6 125+ (90-150) Several moles observed in "sunburst" coloration in courtship behavior, females largely remain in dork-body phase close to substrate their estimates of numbers and sizes as well as behavioral observations in an attempt to reach a consensus on what had been observed. A videographer roamed the area and cap- tured footage of behavior and color changes. A portion of this footage was subsequently analyzed to confirm and refine divers’ observations. Due to logistical and safety constraints arising from work- ing offshore, the dive teams were not able to remain on site until sundown. This is reflected in the timing of the observa- tions in relation to sunset (Table 1). Another set of observa- tions was made on the site for 2 days in August 2005, start- ing 5 days after the full moon. Only 4 divers were involved in these observations. During observations, males were readily identified due to their larger size (all fish >120 cm fork length (FT)) and were counted as males since earlier research had determined the transition size range from female to male to be 110-120 cm FT (Luckhurst and Trott, unpublished data). Following this 44 Bermuda Black Grouper Spawning Aggregation Figure I. Location of black grouper spawning aggregation site on the northeast reef platform of Bermuda. The square (WOO m x 1 000 m) is the approximate area within which black grouper were observed during diving observations and the star symbol is the site with the highest observed density of black groupers during diving observations. protocol, all fishes estimated to be < 120 cm FL were counted as females. Although this species is capable of rapid and dra- matic color changes, there was also some consistency in the appearance of the two sexes with smaller females generally being in dark-phase coloration or the normal species color pattern. The interpretation of the pale body coloration is still to be determined but Paz and Sedberry (2008) report that it is seen in both sexes. The width of the sub -marginal black bands of fin pigmentation on the caudal, anal and pectoral fins is also a useful indicator of the sex of the fish (Crabtree and Bullock 1998). In males, these bands are wider and a more intense black. This contrast is accentuated dun ing spawning times, particularly in the caudal fin of males (with a pale caudal margin). Additionally, males in courtship display show a distinctive color pattern on the head. This cok oration, termed a “sunburst” pattern by Heyman and Kjerve (2008) is described and illustrated (Figure 3C in their paper). The same coloration pattern is termed a “whitediead” phase male by Paz and Sedberry (2008, Figure 3D). 1 use the term “sunburst” in this paper as the more descriptive term to de- scribe this pattern in courting males as well as to use a term which is already in the published literature. Results Site description The spawning aggregation site was located about 10 km offshore on the northeast reef platform of Bermuda (Fig- ure 1) at a depth of about 30 m. The aggregation area is characterized by an extensive substrate of hard bottom with gorgonians and scleractinian corals. The hard bottom is iiv terspersed with sand holes of variable size, often with ridges between them. The depth in the sand holes is about 33 m while the tops of the ridges range from 24-28 m depth. The bottom gently slopes seaward towards the edge of the reef platform with the shelf break at about 55 m depth. The ceiv ter of the black grouper site is located about 500 m from the edge of the reef platform (Figure 1). During the June observations, the surface water temper- ature was 25 °C, however, there was a thermocline present at a depth of about 20 m. Below the thermocline, the tem- perature was 22°C. There were no water temperature data available from the site for the August observations but divers did not report detecting a thermocline. A comparison of the mean monthly water temperature bem^een Bermuda and Belize (Figure 2) reveals that maximum temperatures occur at about the same time of year (August - September). There is a difference of < 2°C between the maxima (27.9°C in Ber- muda in August; 29.5 °C in Belize in September). However, the annual temperature range in Bermuda (18.9-27.9°C) is considerably greater than in Belize (26.5-29.5°C). Behavioral observations Table 1 briefly summarizes the daily observations by divers at the site. One of the notable constraints during the project was the underwater visibility which varied from 15-25 m, coupled with the fact that black grouper are generally wary and do not allow a close approach by divers on open-circuit SCUBA (Eklund et al. 2000, Paz and Sedberry 2008). As a result, this hindered divers’ counts and thus estimates of abundance should be viewed as conservative because it was rarely possible to count all of the fish in the field of view clearly. The abundance estimates are mostly given as a range due to the variability of divers’ counts. Because of the spatial extent of the site, it was not always possible to determine if individual divers were counting the same group of fish. Observations in June 2005 started on the day of the full moon (June 21) when only 30+ fish were counted at the site. The number of fish showed an increasing trend in the fol- lowing days to about 300 fish on June 26 (moon full + 5), although there was a credible estimate of 400 fish on June 22 (Table 1). The size range of fishes remained reasonably con- sistent during the 5 days of observations. Although the data are limited, observations confirmed that although males and females were always present on site, females appeared to in- crease in number during the afternoon and early evening. A small number of females with distended abdomens (a good indirect indicator of spawning readiness) were first observed on June 22 (moon full + 1) and the number of “ripe” fe- males generally increased until observations ceased (Table 1). On June 26* (full moon +5), divers observed the establish- 45 Luckhurst Month Figure 2, Mean monthly water temperature (°C) in Bermuda and Belize. Maximum water temperatures occur during the same period (August - September) but there is greater seasonality in Bermuda than in Belize. ment of male spawning territories with males in courtship displays showing the distinctive “sunburst” color pattern on the head. A minimum of 12 male spawning territories were identi- fied by swimming a transect along a ridge line in the late afternoon and counting the large males which were conspic- uous swimming above the substrate. These male territories were roughly mapped and appeared to be contiguous. These territories were first observed at 1855 h local time (95 miiv utes before sunset) but it is not known if they had formed earlier. Divers surveying in the vicinity of these territories during the same time period did not observe any other large males displaying courtship behavior at the site. A diagrammatic rep- resentation of male courtship behavior (Figure 3) illustrates the different compo- nents of the behavioral sequence. Males began by slowly swimming around the pe- rimeter of their spawning territory about 1-2 m above the substrate. The striking “sunburst” coloration started to become more prominent at this stage. They then turned and swam (in a languid manner) vertically upward in the water column from 9-12 m above the substrate. Upon reaching this height above the substrate, they swam in a circular motion around an imaginary perimeter appearing to delimit their territory as a cylinder (Figure 3). The “sunburst” pattern appeared to become more pronounced when the males were at the top of the cylinder (}. Pitt, pers. comm.. Department of Environmental Protection, Bermuda). After a few minutes, they turned and swam slowly downward to the substrate and apparently resumed the sequence again. No pair spawning rushes or gamete release were observed in this study. How- ever, groups of 6-10 smaller fish in dark-phase coloration (considered to be females) were observed sheltering in the reef infrastructure around the male territories (J. Pitt, pers. comm.) although no interactions with males were detected. Due to the falling light level in the water column, it became increasingly difficult to observe clearly what female behavior was occurring at this time. Interestingly, no other transient spawning species were observed at the site during the five days of observations. It appeared that black grouper domi- nated the area in terms of both number and biomass. The observations 2 months later (August 2005) were lim- ited to 5 and 6 d after the full moon (Table 1). With only 4 divers, it was not possible to survey the site as thoroughly as in June but similar schooling behavior by black grouper was observed during the day and color changes were com- mon. The estimate of the number of fish (150-175) pres- ent on August 24 (full+5) at 1600 h local time compared with the estimate (150+) on the same lunar day in June at 1645 h is similar (Table 1), but no meaningful conclusion can be drawn from this except to confirm that fish were still present in similar numbers 2 months later. The size range of fish between the 2 periods was also similar (Table 1). Again, Figure 3 . Diagrammatic representation of courtship behavior of mole black grouper in temporary spawning territories. Measurements given are: 28 m - depth of water, 20 m - diameter of cylinder, 12 m- height above substrate. See text for details of behavior and timing. 46 Bermuda Black Grouper Spawning Aggregation there were no observations of other transient spawning spe- cies such as groupers or snappers in the area. Using the limited observational data (Table 1), it is possi- ble to describe a general behavioral pattern of black grouper during the afternoon period at the site. The daily sequence of behavior appears to be the following: 1) Loose schools of fish hover above hard substrate, sometimes forming cone- shaped schools of fish 10-15 layers high, no interactions between fish observed (1300 - 1700 h); 2) The number of females on site increases, fish become more active (1700 - 1800 h); 3) Females with distended abdomens appear more numerous and male courtship behavior is observed (1800 - 1900 h); 4) Males establish temporary spawning territories and commence courtship behavior, females shelter in the substrate in the vicinity of male territories (1900 - 1930 h). These observations were made in the week following the full moon but it is not known for how many days this sequence might continue. Discussion The center of the spawning aggregation site, located about 500 m from the edge of the reef platform (55 m depth), ap- pears to be at a greater distance from the shelf edge than other published descriptions of black grouper spawning ag- gregation sites. Black grouper aggregations have been found near shelf breaks or at reef promontories in Belize (Heyman and Kjerve 2008) and Sala et al (2001) reported that a black grouper spawning aggregation was observed in the vicinity of a series of coral ridges in a spur and groove system close to the shelf break at Glover’s Reef, Belize. This site was dominated by Nassau grouper. Whaylen et al. (2004) observed small groups of black grouper at a Nassau grouper spawning aggre- gation site which is located at a shelf break near a drop-off to deepwater in Little Cayman. Claro and Lindeman (2003) indicated that all of the multi-spedes spawning aggregation sites which they documented in Cuba were located near the shelf break. However, the black grouper may be more of a generalist as Paz and Sedberry (2008) observed spawning ag- gregations in a variety of reef formations in Belize. The loca- tion of the Bermuda site, at some distance from the shelf break, tends to support this latter observation. Spawning seasonality in black grouper based on gonad histology has determined that the peak spawning period in populations to the south of Bermuda is from January to March (Florida - Crabtree and Bullock 1998, southern Gulf of Mexico - Brule et al. 2003). Claro and Lindeman (2003) indicated that the peak of the spawning season for black grouper in Cuba was from February to March around the full moon. Diving observations of spawning seasonality at Gladden Spit, Belize indicate that peak spawning in black grouper occurs during the period January - March from 5-14 d after the full moon (Heyman and Kjerfve 2008). A survey of spawning aggregation sites in Belize revealed that peak spawning occurred in January - February and that black grouper were most abundant at sites from the full to the last quarter moon (Paz and Sedberry 2008). In summary, all of the black grouper populations at latitudes south of Ben muda have a winter spawning pattern. However, the summer spawning period Qune - August) for black grouper in Ben muda is consistent with the spawning periods of other local groupers such as red hind (Luckhurst 1998), coney Cephalo- pholis fulva (Trott 2007) and lane snapper Lutjanus synagris (Luckhurst et al. 2000). Thus, it appears that black grouper spawn at the warmest time of year in Bermuda and at a similar temperature, but at the coldest time of year, further south, e.g. Belize (Figure 2). Paz and Sedberry (2008) recorded a bottom temperature range of 24-27°C in Belize at black grouper spawning ag- gregation sites. This minimum is lower than that recorded at Gladden Spit by Heyman et al. (2005) but this may simply be the result of oceanographic variations. The bottom water temperature (22°C) observed at the aggregation site in the present study in June was recorded below a thermodine but it is not known whether a thermodine is a consistent feature of the oceanography at this site during this time period. A bottom temperature of 25°C was recorded at a shallower red hind spawning aggregation site in June (Luckhurst 1998) in the vicinity of the black grouper site. Although diving obser- vations ceased 5-6 days after the full moon, strong evidence of an increase in fish abundance (in June) and imminent spawning (courtship and color changes, both June and Am gust) was observed. However, it is not known how long the aggregation remained intact for either observation period or how long spawning may have continued. Heyman and Kjerve (2008) indicated that the lunar abundance peak of black grouper occurred 5-14 d after the full moon. The data presented here are broadly similar to the detailed observations made in Belize and appear to confirm consis- tent behavioral patterns of black grouper in this spawning aggregation at the northern edge of the species range. The number of black grouper observed in aggregations in Belize over several years ranged from 25 to 375 (Paz and Sedberry 2008), a range similar to that reported here (20+ to 400) for a very limited time period. Heyman and Kjerve (2008) report- ed a maximum total of about 150 fish at a multi-species ag- gregation site at Gladden Spit and Sala et al. (2001) reported a similar maximum (140 fish) at Glover’s Reef. Paz and Sedberry (2008) stated that spawning took place at sunset and Heyman and Kjerve (2008) observed spawning 15-20 min before sunset. As the observations in the present study terminated at least one hour before sunset (Table 1), it is perhaps not surprising that the spawning act (i.e. gamete release) was not observed. Both Paz and Sedberry (2008) and Heyman and Kjerve (2008) described pair spawning in black grouper but neither described the full male courtship behav- ioral sequence documented here. Perhaps this is simply a 47 Luckhurst variation of the basic spawning behavior already described by these authors. Several elements of the behavioral sequence described for Bermuda are similar to those reported for males in “wbitediead” coloration (Paz and Sedberry 2008); these authors determined that this color pattern was observed only in mature males in spawning condition. Furthermore, this coloration was only seen in males during spawning months (December-March) in Belize (Paz and Sedberry 2008). By extrapolation, the observation of this male color phase in both June and August suggests that these are active spawn- ing months in Bermuda. Although no observations were made in July, it is reasonable to assume that spawning could have occurred in that month, leading to a conclusion of a minimum spawning period of 3 lunar months in Bermuda. This is consistent with the 3 month peak spawning period at Gladden Spit (January-March) documented by Heyman and Kjerve (2008). Recent acoustic tagging data collected from the Bermuda site indicates that the aggregation may form monthly for a period of 5-6 months (Trott, Luckhurst and Pitt, unpublished data) but additional data is required to confirm this time period. The important issue of whether spawning is occurring in each aggregation month will require continued monitoring of the site. These data are essential to better define the range and variation of the elements of this aggregation which will allow for more responsive and effec- tive management of this commercially valuable species. Acknowledgements 1 want to thank fisherman K. Gregory for taking me to the site when he first became aware of the pres- ence of this spawning aggregation. His long-term support for the management of spawning aggregations and his contributions to fisheries research have been important factors in progressing this work. There were many people involved in this diving project but they are too numerous to list individually by name. 1 want to acknowledge 1. Murdoch and R. Whayman for organizing this project and providing their own vessels to transport divers to the site. Judie Glee, at reef, did much of the organizational work and coordination for the project. Chris Burville generated much valuable video footage which helped to clarify and refine observations and M. Sturmey provided a number of important observations. Tammy Trott provided the Bermuda water temperature data and W. Heyman the Belize data. Joanna Pitt produced Figure 1. Terry Madeiros created Figure 3 based on information provided to him by the author. Ken Lindeman, W. Hey- man, T. Trott and J. Pitt provided helpful comments on the manuscript. Literature Cited Brule, T, R. Ximena, T Colas- Marrufo, Y. Hauyon, and A.N. Tuz- Sulub. 2003. Reproduction in the protogynous black grouper Mycteroperca bonaci (Poey) from tbe soudiern Gulf of Mexico. Fishery Bulletin 101:463-475. Claro, R. and K.C. Lindeman. 2003. Spawning aggregation sites of snapper and grouper species (Lutjanidae and Serranidae) on the insular shelf of Cuba. Gulf and Caribbean Research 14:91-106. Crabtree, R. E. and L. H. Bullock. 1998. Age, growdi, and repro- duction of black grouper, Mycteroperca bonaci, in Florida wa- ters. Fishery Bulletin 96:735-753. Domeier, M. L. and P. L. Colin. 1997. Tropical reef fish spawning aggregations: defined and reviewed. Bulletin of Marine Sci- ence 60:698-726. Eklund, A.-M., D.B. McClellan, and D.E. Harper. 2000. Black grouper aggregations in relation to protected areas within the Elorida Keys National Marine Sanctuary. Bulletin of Marine Science 66:721-728. Garcia- Cagide, R. Claro, and B. V. Koshelev. 2001. Reproductive patterns of fishes of the Cuban shelf In: R. Claro, K.C. Ein- deman, and E. R. Parenti, eds. Ecology of the marine fishes of Cuba. Smithsonian Institution Press, Washington, D.C., USA, p. 73-102. Heyman, W.D. and B. Kjerve. 2008. Characterization of transient multi- species reef fish spawning aggregations at Gladden Spit, Belize. Bulletin of Marine Science 83:531-551. Euckhurst, B.E. 1996. Trends in commercial fishery landings of groupers and snappers in Bermuda from 1975 to 1992 and as- sociated fishery management issues. In: E. Arreguin-Sanchez, J.E. Munro, M.C. Balgos, and D. Pauly, eds. Biology, fisheries and culture of tropical groupers and snappers. ICEARM Con- ference Proceedings 48, p. 286-297. Euckhurst, B.E. 1998. Site fidelity and return migration of tagged red hinds (Epinephelus gutttatus) to a spawning aggregation site in Bermuda. Proceedings of the Gulf and Caribbean Eisheries Institute 50:750-763. Euckhurst, B.E., J.M. Dean, and M. Reichert. 2000. Age, growth and reproduction of the lane snapper, Lutjanus synagris (Pisces: Eutjanidae) at Bermuda. Marine Ecology Progress Se- ries 203:255-261. Euckhurst, B.E. andTM. Trott. 2009. Seasonally- closed spawning aggregation sites for red hind (Epinephelus guttatus): Bermuda’s experience over 30 years (1974-2003). Proceedings of the Gulf and Caribbean Eisheries Institute 61:331-336. Paz, M. and G.R. Sedberry. 2008. Identifying black grouper (M^y- cteroperca bonaci) spawning aggregations off Belize: Conserva- 48 Bermuda Black Grouper Spawning Aggregation tion and management. Proceedings of the Gulf and Carib- bean Fisheries Institute 60:577-584. Sala, E., E. Ballesteros, and R.M. Starr. 2001. Rapid decline of Nassau grouper spawning aggregations in Belize: Fishery man- agement and conservation needs. Fisheries 26:23-30. Teixeira, S.F., B.P. Ferreira, and I.P. Padovan. 2004. Aspects of fishing and reproduction of the black grouper Mycteroperca bo- naci (Poey, 1860) (Serranidae: Epinephelinae) in Northeastern Brazil. Neotropical Ichthyology 2:19-30. Trott, T.M. 2004. Preliminary analysis of age, growth, and repro- duction of coney (Cephalopholis fulva) at Bermuda. Proceedings of the Gulf and Garibbean Fisheries Institute 57:385-400. Whaylen, L, G.V. Pattengill-Semmens, B.X. Semmens, P.G. Bush, and M.R. Boardman. 2004. Observations of a Nassau grouper, Epinephelus striatus, spawning aggregation site in Little Gayman, Gayman Islands, including multi-species spawning information. Environmental Biology of Fishes 70:305-313. 49 Gulf and Caribbean Research Volume 22 Issue 1 2010 Evaluating Management Actions for Spotted Seatroup Cynoscion nebulosus, in Mississippi with an Age-Structured Projection Model Richard S. Fulford University of Southern Mississippi J. Read Hendon University of Southern Mississippi DOI; 10.18785/gcr.2201.06 Follow this and additional works at: http:/ / aquila.usm.edu/ gcr & Part of the Marine Biology Commons Recommended Citation Fulford; R. S. andj. Hendon. 2010. Evaluating Management Actions for Spotted Seatrout; Cynoscion nebulosus, in Mississippi with an Age-Structured Projection Model. Gulf and Caribbean Research 22 (l): 51-61. Retrieved from http://aquila.usm.edu/ gcr/vol22/issl/ 6 This Article is brought to you for free and open access by The Aquila Digital Community. It has been accepted for inclusion in Gulf and Caribbean Research by an authorized editor of The Aquila Digital Community. For more information, please contact Joshua.Cromwell^usm.edu. Gulf and Caribbean Research Vol 22, 51-61, 2010 Manuscript received December 16, 2009; accepted February 10, 2010 EVALUATING MANAGEMENT ACTIONS FOR SPOTTED SEATROUT, CYNOSCION NEBULOSUS, IN MISSISSIPPI WITH AN AGE-STRUCTURED PROJECTION MODEL Richard S. Fulford^ and J. Read Hendon^ ^Department of Coastal Sciences and ^Center for Fisheries Research and Development, Gulf Coast Research Laboratory, University of Southern Mississippi, 703 East Beach Drive, Ocean Springs, MS 39564, email: Richard.Fulford@usm.edu Abstract: Spotted seatrout, Cynosdon nebulosus, is an important recreational fishery in the coastal waters of the Gulf of Mexico and is the most sought after gamefish in coastal Mississippi. The management of C. nebulosus is state-specific, and unlike other similarly managed species, data on both population structure and movement support the existence of local sub-stocks. It is important for each state to clearly examine its own sub-stock in the context of its own state fishery in order to properly manage for local sustainability. We used an age-structured assessment model to examine the status (1993-2005) of the Mississippi C. nebulosus population and to project forward several probable management actions (i.e., length limits) while also accounting for uncertainty in both fishing mortality and annual recruitment. Model results suggest annual fishing mortality for Mississippi C. nebulosus is close to but that spawning stock biomass (SSB) is not below This sug- gests the sub-stock is currently stable, but with high fishing pressure and a high dependence on annual recruitment to the fishery. Projections suggest that when uncertainty in angler effort and annual recruitment are included in the analysis, more conservative management actions are warranted in order to achieve both higher fishery yield and stable SSB. Introduction Spotted seatrout, Cynosdon nebulosus, is an important rec- reationally and commercially harvested species in all states bordering the northern Gulf of Mexico (GOM, GSMFC 2001). In particular, the landings of C. nebulosus have been increasing in coastal Mississippi state waters since 1995 as spotted seatrout are the dominant target of recreational am glers within the state. While historically the commercial bar- vest of C. nebulosus has been high, recreational landings have represented over 90% of total landings since 1981 (NMFS Fisheries Statistics Section unpublished data). As a result, the recreational management of C. nebulosus in Mississippi is a significant issue that receives a lot of public attention. Although C. nebulosus is harvested across the northern GOM coast, there is evidence that there is not a single GOM stock but multiple sub-stocks. Cynosdon nebulosus is a non-migratory estuarine-dependent species (Gold and Richardson 1998) that can be found in a variety of coastal habitats, but is generally found in shallow water (< 1 m) as- sociated with rooted vegetation (GSMFC 2001). Data from tagging studies in Mississippi and elsewhere indicate that individual adult fish are highly unlikely to travel more than 15 km both within and betw^een years (Moffett 1961, Baker and Matlock 1993, Hendon et al. 2002). These data support the idea that there are sub-stocks of C. nebulosus differem tiable at a scale consistent with each GOM state, and it is reasonable to generate both independent stock assessments and management regulations for each GOM state. This is consistent with existing management in that C. nebulosus are managed independently within each state as a part of a cooperative agreement between states (GSMFC 2001). Regulations for the recreational harvest of C. nebulo- sus vary greatly by GOM state (Table 1). Yet, all five states have adopted a proxy for maximum sustainable yield (MSY) based on the spawning potential ratio (SPR). The SPR measures the reproductive potential of the fished stock in comparison to the reproductive potential of the virgin (i.e., unfished) stock. The SPR proxy can be estimated from age- structured landings data and provides an easily interpretable benchmark against which to determine stock status. Not all states have a target SPR value but all 5 states report the SPR for their state as part of their respective stock assessment. The recreational fishery for C. nebulosus in Mississippi is particularly important in comparison to other state -mam aged fisheries. An analysis of angler interview data for Mis- sissippi indicates that C. nebulosus is the dominant target spe- cies among anglers in Mississippi (National Marine Fisheries TABLE I. Current fishery regulations for Cynosdon nebulosus by Gulf of Mexico (GOM) state. SPR— spawning potential ratio. State Minimum size limit (in) Daily Bag limit Target SPR Florida 15-20* 5 35% Alabama 14 10 30% Mississippi 13 15 n/a Louisiana 12 25 18% Texas 15-25** 10 30% *FL allows 1 fish/day > 20" TL ** TX allows 1 fish/day > 25" 51 Survey CPUE (fish yr'’’) Catch biomass (mt) Fulford and Hendon Figure I. Time series of catch for Cynoscion nebulosus in Mississippi. A. Female recreational catch. B. Index catch per unit effort (CPUE) from fishery-independent data. Arrow in upper panel indicates only major regulatory change between 1 993 and 2005. Error bars are ± 1 se. Service Fisheries (NMFS) Statistics Division, pers. comm., Mississippi Department of Marine Resources (MS-DMR), unpublished data ). However, Mississippi has not established formal benchmarks for assessment of stock status and while benchmarks have been established in several other states, these benchmarks, and the associated management regula- tions, should not be applied to assessment of the Mississippi stock without some examination of the projected effect. Management of C. nebulosus in Mississippi has undergone several changes over the last 30 years, but has been rela- tively stable betv^een 1995 and 2007. Since initial adoption, recreational management regulations have included both a minimum length limit and a daily quota (i.e., bag limit) for harvest. The daily quota has ranged from 10 to 50 but has been set at 15 since 1996. Minimum length limits have ranged from 12” (305 mm) to 14” (356 mm) total length (TL) but were set at 14” from 1995 to 2006. In 2007 the minimum length limit was reduced to 13” (330 mm) TL. The recent change in the length limit was initially proposed based on public comments that the 14” length limit resulted in a high level of sub-legal catch and release for near-shore anglers (MS-DMR, unpublished public comments). No for- mal stock assessment of C. nebulosus in Mississippi is avail- able to evaluate this change in the management regulations. Management regulations for recreational fisheries, like those for commercial fisheries, are primarily focused on maximizing harvest and/or angler satisfaction while also maintaining a stable population (Hilborn and Walters 1992). Achieving this dual objective in a recreational fish- ery is complicated by highly variable effort, highly variable catch per unit effort (CPUE), and low reporting rates for landings. Common management options include set- ting a maximum CPUE (i.e., daily quotas) combined with length limits to protect spawning stock biomass (SSB) and maintain a target SPR. The influence of either bag limits or minimum length limits on fishing mortality is greatly affected by variability in the rate of recruitment, as well as changes in angler effort through time. Evaluating the ap- propriateness of management actions under these circum- stances can be difficult and involves much uncertainty regarding the effect on long-term population stability. Quantitative models offer a powerful tool for both the assessment of fishery stocks and the evaluation of poten- tial management decisions (Hilborn and Walters 1992). In particular, statistical catch at age (SCAA) models allow indi- vidual cohorts to be tracked through time as a method for estimating total population mortality rate, recruitment, and SSB. Such models also provide a framework for the evalua- tion of management actions by projecting fishery yield and SSB based on estimated changes in fishing mortality and future recruitment. This approach has been used to estab- lish future status and compare management actions for At- lantic cod (Gadus morhua, Reich and DeAlteris 2009), lake whitefish (Coregonus clupeaformis, Mohr et al. 2007), and North sea plaice (Pleuronectes platessa, Hoff and Frost 2008). In the case of C. nebulosus, SCAA models provide an ap- proach for exploring the relative influence of the range of management regulations applied across the 5 COM states on the Mississippi stock. This analysis is not therefore a formal assessment of the stock, but rather an exploration of possible management outcomes with a stock assessment model that we hope is a step towards a formal assessment in the future. In this study we applied an SCAA model to examine the Mississippi population of C. nebulosus with 3 objectives: (1) to estimate current stock status of the Mis- sissippi population relative to MSY-based benchmarks, (2) to evaluate the range of minimum length limits currently applied to C. nebulosus across the COM in terms of their relative effect on population sustainability in Mississippi, and (3) to explore the effect of changes in future recruit- ment and angler effort on population sustainability and how 52 Cynoscion nebulosus Age-Structured Model these factors should affect management decisions. The fo- cus on minimum length limits as the primary management tool was based on current discussions regarding manage- ment of C. nebulosus in Mississippi and the need to under- stand the influence of length limits on population stability. Methods Data used for this model assessment of C. nebulosus were a combination of fishery independent and fishery dependent data. Recreational landings (1993-2005) of C. nebulosus were estimated from creel data collected in Mississippi as a part of the Marine Recreational Fisheries Statistics Survey (MRFSS; NMFS Fisheries Statistics Section unpublished data; Figure lA). These data included both landings and dead discards as model input. A time series (1993-2005) of fishery indepen- dent catch per unit effort (CPUE) was used to constrain the 200 300 400 500 600 Tota! length (mm) Figure 2, Metrics for Cynoscion nebulosus in Mississippi. A. Sex ratio. Black bars are males and grey bars females. B. Total length at age for females. Reference lines indicate cutoff for 12" {—), 13" (—), and 14" (■■■) length limits. C. Biomass at total length for females. Points in panels B and C are individual fish (n = 3,524). model and came from a gillnet survey conducted monthly at eight survey sites along the Mississippi Gulf coast (Figure IB; University of Southern Mississippi - Center for Fisher- ies Research and Development (CFRD) unpublished data). While there is a commercial harvest of C. nebulosus in Missis- sippi, these landings are small (about 10% of total landing; NMFS Fisheries Statistics unpublished data) and are not affected by recreational management actions. Commercial harvest is almost entirely hook and line with a 14” length limit and a 40,000 lb annual quota since 1986 (MS-DMR, unpublished data). Commercial harvest was included in the model as a separate but constant fishing mortality term. Length frequency of the catch as reported by MRFSS was converted to age frequency for females only based on esti- mates of sex ratio at length (Figure 2A) and year-specific age -length keys (ALK) that were both based on C. nebulo- sus collected, sexed, and aged by the University of South- ern Mississippi CFRD (n = 3,524, mean = 244/yr). Model input also included estimates of percent maturity at age for spotted seatrout in Mississippi (Brown -Peterson and War- ren 2001, Brown-Peterson et al. 2002). Growth rates of female spotted seatrout in Mississippi were also estimated from size -at- age and biomass -at- age data collected inde- pendent of the fishery (Figure 2B, C; 1993-2006, CFRD unpublished data). Natural mortality of spotted seatrout in Mississippi was estimated to be 0.3 for all model simu- lations based on an analysis of longevity and growth pa- rameters used in previous assessments (GSMFC 2001). Model description The model assessment was conducted using a SCAA Model (ASAP2; NMFS NEFSC Eisheries Toolbox http:// nft.nefsc.noaa.gov/). The ASAP2 model is a non-linear optimization model that estimates average fishing mortality and spawning stock biomass by age class based on minimi- zation of an objective function that describes model fit to fishery landings, index CPUE, as well as fishery and index age compositions. Nine age classes were included in model simulations (age 0-8) with no plus group. The model fit was constrained both by estimates of variability for each data in- put source (Table 2) and a Beverton-Holt stock-recruitment function with an initial steepness of 0.6 (Haddon 2001). The initial steepness value was chosen to be neutral, how- ever final steepness was fully estimated by the model and was not strongly influenced by the initial value. Error structure for both fishery landings and index CPUE were assumed to be lognormally distributed while error structure for the age compositions had a multinomial distribution. Effective sample size for the multinomial distribution was set at 200 for all years based on mean annual coverage of the age data used to build the ALK. The ASAP 2 model has been used to conduct formal stock assessments of several fish stocks in- cluding red grouper, Epinephelus morio, and yellow tail floun- der, Pleuronectes ferrugineus, (Schirripa et al. 1999, Legault et 53 Fulford and Hendon TABLE 2, Input parameters for the age-structured model. Initial value is the value input to the model which remained constant if Fixed (F), but could change during the optimization if Estimated (E). Selectivity values for length limits of 12 and 13" were only used to perform model projections. Parameter Initial value F/E Final value Model component Natural mortality 0.3 F 0.3 Estimate non-fishing mortality Steepness 0.6 E 0.8 Stock-recruitment curve CV of rec. catch 0.2 F 0.2 Weight on model fit CV of comm, catch 0.1 F 0.1 Weight on model fit CV of recruitment 0.5 F 0.5 Weight on model fit CV of Index catch 0.2 F 0.2 Weight on model fit Selectivity age-0 12" 0.1 F 0.1 Age-specific component of directed fishing mortality used in projection Selectivity age- 1 12" 1 F 1 Age-specific component of directed fishing mortality used in projection Selectivity age >2 12" 1 F 1 Age-specific component of directed fishing mortality used in projection Selectivity age-0 1 3" 0.05 F 0.05 Age-specific component of directed fishing mortality used in projection Selectivity age- 1 13" 0.8 F 0.8 Age-specific component of directed fishing mortality used in projection Selectivity age >2 13" 1 F 1 Age-specific component of directed fishing mortality used in projection Selectivity age-0 14" 0.03 *E/F 0.03 Age-specific component of directed fishing mortality used in projection Selectivity age- 1 14" 0.6 *E/F 0.54 Age-specific component of directed fishing mortality used in projection Selectivity age >2 14" 1 *E/F 1 Age-specific component of directed fishing mortality used in projection Unexploited stock size 455,000 E 492,000 Virgin stock size used to estimate benchmark SPR Index selectivity 1 E 0.2 (age-0) Age-specific cotchobility of gillnet survey (all ages) 0.8 (age-1) 1 (age-2-i-) *Selectivity values for 14" limit v^ere used for initial optimization and v^ere estimated. These values were then fixed for the projection. al. 2006). The ASAP2 model was used (1) to estimate stock status (1993-2005) of C. nebulosus including estimates of SSB and age-specific fishing mortality rate (F^), (2) to esti- mate uncertainty for current stock status, and (3) to conduct projections of relative SSB and female fishery yield for a range of management scenarios (See Model projections sec- tion). The model input data were for females only because of our emphasis on the influence of management on repro- ductive capacity and population stability. The influence of management on relative fishery yield is presented as a tool for discussing the tradeoffs between population stability and harvest but is not a measure of total fishery yield as about 14% of the total harvest is estimated to be male (Figure 2A). Reference benchmarks for the fishery were selected based on common benchmarks used for stock assessments of C. nebulosus in other states (GSMFC 2001). No benclv marks have been established for C. nebulosus in Missis- sippi, however several other states have chosen reference points based on SPR (Table 1). For this assessment we re- port MSY, Fishing mortality rate at MSY (F^^^^^, and Fishing mortality rate at an SPR of 30% (F^^). Fishery refer- ence points are addressed in more detail in the Discussion. Uncertainty estimates for model output including fishery benchmarks were based on a Markov Chain Monte Carlo (MCMC) simulation involving 200 model runs selected from 200,000 overall runs with an initial burn in of 1,000 runs. Each run is a repeat of the base model with randomly select- ed values for each input parameter from the appropriate dis- tribution with the best fit parameter value as the mean. The MCMC approach is a well-established method for estimating uncertainty in model estimates based on variability in model parameters (Haddon 2001). All parameters were assigned a lognormal error structure with the exception of catch at age data which were assigned a multinomial error structure. In addition a retrospective analysis was conducted that involved a series of model simulations with the final year reduced by 1 to identify any retrospective patterns in the data time series. Model projections The baseline results of the SCAA model were projected forward for a period of 12 yr (2003-2015) based on a range of both management actions and biological conditions. This projection period was chosen to allow for an initial transition period (~5 yr) to a stable outcome. Projections were conducted at three length limit restrictions 12”, 13” and 14” and 4 projected fishing mortality rates (F ,125% of F , 150% of F , and F,,^,). Length limits were simu- lated with shifts in the age-specific selectivity of the fishery in the model (Table 2). Selectivity changes were based on the 54 Cynoscion nebulosus Age-Structured Model probability of a legal sized fish being in a particular age class, which was estimated using a cumulative ALK (1993-2005; CFRD unpublished data). These age-specific probabilities were also adjusted to account for delayed release mortality of sub -legal fish based on reported numbers of fish released alive (NMFS Fisheries Statistics Section unpublished data) and an estimated 72 h mortality rate of 10% based on an observational study (n = 478 fish; R. Hendon, unpublished data). All other components of the base model run remained consistent with the optimized results given in Table 2. In addition, these projections were repeated with one of 2 re- cruitment patterns. Either annual recruitment of age-0 fish was allowed to shift according to the modehestimated stock recruitment curve or age-0 recruitment was held constant at an average value for the last 5 yr of the dataset (2000-2005). The constant recruitment option assumes that recruitment may have reached a biological maximum (e.g., habitat limn tation). The output from these projections is a time series for SSB and fishery yield over the proceeding 5 yr based on management and biological conditions. Output from model projections was relative change in SSB and female yield expressed as the proportion of either SSB or yield in 2006 under current conditions for length limits and fishing mortality. Differences betw^een the model projections were based either on differences in linear slope analyzed with an ANCOVA or differences in terminal year value with an ANOVA. Results The SCAA model provided a good fit to the overall ob- jective function with most of the error contained in the fit to fishery age composition (71%). This was expected as the age composition of the catch was dominated by age-1 and age -2 fish leaving little latitude for the model fit. Most of the lack of fit occurred as an overestimation of age-1 fish and underestimation of age -2 fish in the catch, but the total deviance was small (Figure 3). The stock recruitment func- tion provided a meaningful constraint on the abundance of age-0 fish each year with a final steepness value of 0.8. The MCMC and retrospective analyses indicated a low level of variability about the predictions of average F (across age classes) and SSB with a generally increasing pattern in uncertainty towards the final year in the assessment (Figure 4). In addition, the retrospective analysis suggested retro- spective pattern in the model fit was present with strongest influence in the final 2 yr of the assessment with CV in- Age (yr) Figure 3. SCAA model fit. A. Index CPUE. B. Total commercial catch biomass. C. Total recreation catch biomass. D. Age composition of the recreational catch pooled across years. Closed symbol indicates observed data and open symbol indicates prediction of the age- structured model. Error bars are ± Ise. 55 Average F Spawning stock biomass (mt) Fulford and Hendon Figure 4. Time series of model simulations based on a Monte Carlo analysis. A. Median spawning stock biomass (SSB). B. Aver- age fishing mortality rate (F). Solid line— Monte Carlo analysis, dashed error Tmes~5th and 95th percentiles. creasing to > 1, so projections were initiated in 2003 and run for an additional 2 yr (i.e., final projection year 2015) to minimize the effects of retrospective pattern on the pro- jections. Overall variability in model estimates (model CV 16%, 1993-2005) was used to analyze projection results. Spawning stock biomass in 2003 was estimated in the model to be 169 mt (95% CL 75-426 mt) and the prob- ability that exceeded SSB was estimated to be 71% (Figure 5 A). The model estimated an increas- ing trend in SSB bem^een 1993 and 2001 and then a de- creasing trend until 2003 (Figure 4A). The net change in SSB between 1993 and 2003 (39 mt) was estimated to be greater than the uncertainty of model output (95% Cl ± 23 mt), suggesting a significant increase over this period. Fishing mortality rate in 2003 was estimated to be 0.65 (95% CL 0.50-0.82). The probability that current F exceeds F^^^ is about 17% (Figure 5B). The trend in average fish- ing mortality was positive over the entire time series (Fig- ure 4B), however the trend is flat from 1994 to 2000 after which F began to rise more rapidly suggesting most of the increase in fishing mortality has occurred in recent years. Forward projections of the model indicated that chang- es in the trend in relative female yield for the recreational fishery changed as a function of length limits, but the mag- nitride and direction of change is dependent on the level of fishing mortality and the projected recruitment rate (Fig- ure 6). Using the model stock recruitment function and F at or above F , relative female yield was at or above 1 in 2006 at all size limits (Figure 6A, C, E). Relative fe- male yield increased initially at all size limits for F and 125% of F , but then began to decrease after 2008 with current ^ the most rapid decrease for the 12” size limit. The slope of relative yield at 12” was significantly different (ANCOVA; p < 0.008) than either 13 or 14” at F and at 125% of F . The slopes were all negative at 150% of F , but were not significantly different (p = 0.074). At rela- tive female yield increased monotonically to over 200% of the yield in 2006 with no significant difference in slope between length limits (ANCOVA; p = 0.3; Figure 6G). The influence of length limits and fishing mortality rate on relative yield were reduced if recruitment of age-0 fish was capped at the 5 yr average (Figure 6B, D, F, H). Rela- tive yield declined initially for all F at or above F , but the slope increased to near zero by 2010. For the trend was initially positive and then flat after 2008 for the rest of the projection period (Figure 6H). However, no significant differences in slope were detected (p > 0.1) among length limits at any value of F. The stable value for relative yield after 2010 was not significantly different among levels of F (AN OVA; p > 0.1) or among length limits (AN OVA; p > 0.1). This recruitment driven stable point for the projec- tion was 60-70% of the estimated female yield in 2005. Spawning stock biomass was also projected to be inflm enced by length limit, recruitment pattern, and fishing mon tality rate (Figure 7). If a stock recruitment function was used in the projection with F = F , SSB was predicted to increase by 66% by 2015 with a length limit of 14”, but decline by 23% and 53% at 13” and 12” respectively (Figure 7A). If F was set at either 125% or 150% of F , then the trend in SSB had a negative slope for all length liim its with SSB declining by 60-80% at 125% of F and 80-95% at 150% (Figure 7C, E). The slope for 12” was sig- nificantly lower at 125% of (ANCOVA, p = 0.004) than the slope at either 13” or 14”. No significant differ- ence in slope was detected at 150% of F (p = 0.64). For F^q„/^ the projected trend in SSB had a strongly positive slope for all three length limits with the slope at 12” significant- ly lower (p < 0.001) than at either 13” or 14” (Figure 7G). Model projections of SSB changed somewhat when re- cruitment of age-0 fish was capped at the 5 yr average (Figure 7B, D, F, H). Projected SSB between 2003 and 2015 declined initially for all length limits and all F at or above F . The ^ ® current TABLE 3. Model generated reference benchmarks for the C. nebulosus recreational fishery in Mississippi. Values in parentheses are 95% confidence limits. Benchmark Estimated value ^current 0.65 (0.50-0.82) F msy 0.7 (0.63-0.77) MSY 24.9 mt SSB msy 120 mt (15-453) ^30% 0.37 56 Cynoscion nebulosus Age-Structured Model Figure 5. Cumulafive density function the model run based on Monte Carlo analysis. A. Spawning stock biomass (SSB). B. average F . for the terminal year. Vertical lines indicate model estimates of current / ^.sx respectively. trend was flat for all length limits at (Figure 7H). All pro- jections with a fixed recruitment rate stabilized by 2010 and the final year SSB differed by level of F, but only the ending value at (21% increase from 2003) differed significantly from the other three values of F examined (AN OVA, p < 0.03). Discussion Projections made with an SCAA model are sensitive to uncertainty in future conditions such as recruitment and fishing effort. In some cases, patterns in future conditions can be well estimated and used to make specific predictions of future stock status (Mohr et al. 2007, Hoff and Frost 2008, Reich and DeAlteris 2009). In the case of C. nebulosus in Mis- sissippi, too much uncertainty exists regarding future recruit- ment and angler behavior to make predictions. Yet, we can project the state of the stock in the future relative to current conditions and in so doing gain some useful insight on the sensitivity of the population to specific actions. There is both process uncertainty and observation uncertainty pres- ent in such projections that are difficult to separate and quantify. However, the use of an MCMC approach to esti- mate overall uncertainty should allow for a combined esti- mate, which allows for an estimate of the risk of exceeding benchmarks associated with specific management actions, as well as trends in relative stock condition through time. The results of the model analysis indicate that the influ- ence of changes in the minimum legal length limit for C. nebulosus is dependent on both future recruitment and fu- ture changes in angler effort. Yet, certain consistencies did emerge across the range of length limits tested in the model. The largest length limit of 14” produced the highest relative yield in the terminal year and the highest SSB in all but the most conservative level of fishing mortality rate. In contrast, the smallest length limit (12”) produced the lowest terminal year relative yield and the lowest projected SSB in all simula- tions. There was variance in the similarity of projected out- comes for a length limit of 13” and it seems that 13” and 14” differ most as management actions under current condi- tions and are more similar if fishing mortality is either raised or lowered significantly. Fishing at always produced the highest yields and the largest increase in SSB across all mini- mum length limits. In the case of relative yield may not comprehensively emulate objectives for a recreational fishery, as this increase is driven by the increase in abun- dance of larger, older fish. The model indicated that stock abundance would increase as well, but not as much as yield. When recruitment was held constant at the 5 yr average, the projection results always stabilized after about 5 yr and remained constant thereafter. The exact level of stability was dependent on fishing mortality rate, but not on the mini- mum length limit, which suggests that if current recruitment levels are limiting then a lot of fishery yield is lost as pre -re- cruit mortality even at lower levels of F. This finding supports the idea that recruitment limitation (e.g., via habitat loss) may be as important as management actions to fishery yield. Recruitment of C. nebulosus in coastal Mississippi has not been comprehensively examined, but research suggests coastal aquatic vegetation is an important limiting compo- nent. Cynoscion nebulosus has been shown to be highly de- pendent on rooted macrophytes for nursery habitat (Rozas and Minello 1998, GSMFC 2001), and a study of nursery source habitat in Mississippi Sound indicated that a higher proportion of adults had a chemical signature consistent with a nursery area having a higher than average density of sea grasses (Comyns et al. 2008). Juveniles may also be using emergent macrophytes such as salt marsh as habitat (Chester and Thayer 1990), but studies have found a strong preference for both emergent and submerged rooted mac- rophytes (GSMFC 2001). Both submerged sea grass and emergent marsh have been in general decline in coastal Mississippi (Moncreiff et al. 1998) and this suggests that nursery habitat may be in decline, which will contrib- ute to limiting future recruitment to the fishable stock. If nursery habitat might be limiting to recruitment in the future, it becomes more important to establish an SPR benchmark that is adequate to allow for reductions in juve- nile survivorship. Only one scenario was tested that involved a theoretical benchmark SPR (F^^,/) and the result was much higher SSB with a stock-recruitment relationship, but no 57 Fulford and Hendon 2004 2006 2008 2010 2012 2014 2016 2004 2006 2008 2010 2012 2014 2016 "h— ' _C0 CD 0^ 2004 2006 2008 2010 2012 2014 2016 2004 2006 2008 2010 2012 2014 2016 Figure 6 . Model-based projections of relative female yield for the Cynoscion nebulous recreational fishery. Relative fishery yield is expressed as proportion of estimated yield in 2006 under current conditions for F and minimum length limits. Panels are for 4 levels of fishing mortality (A, B - C, D -125% E, F - 150% and G, H - F^^J and either model predicted (left) or constant (right) recruitment. Each panel contains a projection for 3 theoretical length limits: 12" (•), 13" (o), or 14" (A). See text for details. real difference if recruitment was capped. This outcome demonstrates that management actions to mediate loss of es- sential habitat may have limited value once the habitat is lost. While Mississippi does not have a target SPR, data sug- gest the current SPR of the Mississippi stock is below the reported target values for other GOM states (Table 1). The transitional SPR has been independently estimated to be be- tween 6 and 13% from 1993 to 2005 (R. Hendon, unpub' lished data). The applicability of these benchmark values for the Mississippi stock has not been evaluated and our use of should not be interpreted as an endorsement of this value for management. Yet, our model projections suggest 58 Cynoscion nebulosus Age-Structured Model that allowing stock SPR to fall further is likely to result in a declining SSB and relative yield, while increasing SPR ultP mately will both increase yield and SSB, despite the decline in harvest needed to accomplish this objective. Changes in the minimum length limit should influence stock SPR, as indicated by changes in projected SSB in the model, but other factors affecting fishing mortality are also important. Changes in fishing mortality not associated with manage- ment regulations are most strongly affected by changes in an- gler effort. Angler effort in the future is highly uncertain as 2004 2006 2008 2010 2012 2014 2016 2004 2006 2008 2010 2012 2014 2016 5 n 4 3 2 - 1 - 0 1 1 1 1 1 2004 2006 2008 2010 2012 2014 2016 1.32 -I 1.28 - 1.24 - 1.20 - 1.16 - 1.12 - 1.08 - H o/ V 5-0 ■o .. o ■o- O - O -O o 2004 2006 2008 2010 2012 2014 2016 Figure 7, Model-based projections of relative spawning stock biomass (SSB) for Cynoscion nebulosus. Relative biomass is expressed as the proportion of SSB estimated in 2006 under current conditions for F and minimum length limits. Panels are for four levels of fishing mortality (A, B - F C, D -125% F E, F - 150% F and G, H - ond either model predicted (left) or constant (right) recruitment. Each panel contains a projection for three theoretical length limits: 12" (•), 13" (oj, or 14" (A). See text for details. 59 Fulford and Hendon recreational fishing has been shown to respond to a variety of influences including costs of fishing, individual objectives of fishing (e.g., food vs. trophy fishing), and angler access (GSMFC 2001). In the case of C. nebulosus in Mississippi, creel data indicate that angler effort has increased from around 800,000 trips/yr in 1993 to over 1,000,000 trips/yr between 2000 and 2004 (MS-DMR unpublished data). Mod- el results suggest that while fishing mortality has been consis- tently close to since 1993, recreational catches have been slowly increasing over this time period. Commercial catches have been falling but this is thought to be a result of decliiv ing effort. This suggests that both population abundance and angler effort have increased since 1993. The model estimated an increasing trend in F and a decreasing trend in SSB since 2000, which further suggests that population abundance may have reached a peak while angler effort continues to rise. If this is true, any increase in fishing mortality due to changes in the length limit would only increase this trend. Creel data indicate that a reduction in the legal length limit for C. nebulosus may also result in an increase in angler effort in the future. Fish size distribution appears to shift upwards away from shore due to the higher abundance of mature females associated with the barrier islands (CSM- FC 2001), so there is a presumed negative relationship between minimum length limits and angler access since shore -bound or small boat anglers have more access to smaller fish. The true response is highly uncertain. In fact there is a high reported catch and release for near shore sub-legal fish when the length limit is 14” (MS-DMR, uiv published data), and a reduction in the size limit may re- suit in a transfer of release mortality into harvest. However, data also suggest release mortality, even after 72 h, is less than 10% (R. Hendon, unpublished data), and while ille- gal harvest may increase this number, it remains likely that a reduction in the length limit is likely to increase the tan get value of C. nebulosus and result in more angler effort. The model projections combining lower length limits (12-13”) with increased fishing mortality are more like- ly to be consistent with angler behavior under these as- sumptions. The current average F for female C. nebulosus in Mississippi is very close to F^,^. Our analysis suggests that after accounting for uncertainty, population stabih ity is more likely if F remains stable or is reduced. In pan ticular, the recent downward trend in SSB suggests that any further increase in harvest will negatively affect SPR. Independent of angler response, model results suggest a 14” size limit is most consistent with maintaining or iin creasing SPR. Estimates of SPR for C. nebulosus in Missis- sippi appear very sensitive to fishing mortality for age-1 fish. Cynoscion nebulosus are 80% mature by age- 2 but only 45% mature at age-1 (BrowinPeterson and Warren 2001) and data suggest they have a mean size of 12” at age-1 and a mean size of 14.6” at age-2 (CFRD unpublished data). Based on model input data and accounting for differences in length-specific fecundity (Brown- Peterson and Warren 2001), annual egg production is 41% from age-1 and 44% from age -2 fish, so spawning potential is highly dependent on newly-mature age-1 and age -2 fish and should be very sensitive to an increase in mortality for these fish. The best strategy for population stability, based on model results, is to protect age-1 fish until they spawn at least once. Model projections indicate this strategy might be possible at either a 13 or a 14” length limit, but after accounting for future un- certainty is most likely with a 14” length limit. The positive trend in SSB predicted by the model between 1993 and 2000 also suggests that the 14” size limit combined with lower an- gler effort resulted in a stable population over this period. Statistical catch at age models are valuable tools for both estimating stock status and projecting the effects of future changes in condition. One key strength of the approach is the ability to account for uncertainty in the model estimates. Uncertainty can have many sources but the most common are uncertainty due to model structure (i.e., process) and uncertainty due to variability in the data (i.e., observation uncertainty). In particular the model is sensitive to observa- tion uncertainty present in estimates of catch at age taken from MRFSS surveys. The MRFSS program has been criti- cized for observer bias and inconsistent levels of coverage through time (NRC 2006). This has resulted in a high coef- ficient of variation between years for these data that must be carried through to model output. In this case, the impor- tance of these data to overall model fit was down-weight- ed to partially account for bias in the MFRSS data and its influence on uncertainty estimates is thought to be small. Cynoscion nebulosus should be managed on a state by state basis based on the results of tagging (e.g., Hendon et al. 2002) and genetic (Cold et al. 1999) studies. Several states along the Culf Coast have established SPR-based benchmarks for assessing stock status but over a fairly broad range of rela- tive SSB (Table 1). Our results suggest that in Mississippi, the most robust strategy is to protect SSB at age-1 in order to maintain a high level of recruitment. Cynoscion nebulosus is the dominant sportfish in coastal waters (CSMFC 2001) with a higher directed effort on this species in comparison to other neighboring states with a more diverse inshore fishery. While it is difficult to make a definitive statement regarding why the Mississippi fishery may require more conservative benchmarks for population stability it is likely related to this high directed effort and the decline in coastal vegetation over time. In general it will be important to set meaningful benchmarks for population stability that reflect local condi- tions, and these actions can be appropriately evaluated using quantitative tools such as SCAA models prior to implemen- tation, which should greatly improve the manager’s ability to maintain a stable and productive fishery for the future. 60 Cynoscion nebulosus Age-Structured Model Acknowledgements This work would not have been possible without the time and effort of a great many peo- pie and we thank G. Grey, W. Dempster and all other CFRD staff that aided in the collec- tion and processing of data for this research. We also acknowledge M. Buchannan, M. Hill, and W. Devers of the Mississippi DMR for their time and contribution to the collection of fishery-de- pendent data. This work was funded by a grant from the Mississippi DMR Tidelands Trust Fund. Literature Cited Baker, W.B. and G.C. Matlock. 1993. Movement of spotted se- atrout tagged in Trinity Bay, Texas. Northeast Gulf Science 13:29-34. Brown-Peterson, N.J. and J.W. Warren. 2001. The reproductive biology of spotted seatrout, Cynoscion nebulosus, along the Mis- sissippi Gulf Coast. Gulf of Mexico Science 2001:61-73. Brown-Peterson, N.J., M.S. Peterson, D.L. Nieland, M.D. Mur- phy, R.G. Taylor, and J.R. Warren. 2002. Reproductive biol- ogy of female spotted seatrout, Cynoscion nebulosus, in the Gulf of Mexico: differences among estuaries? Environmental Biol- ogy of Fishes 63:405-415. Chester, A.J. and G.W. Thayer. 1990. Distribution of spotted se- atrout (Cynoscion nebulosus) and gray snapper (Lutjanus griseus) juveniles in seagrass habitats of western Florida Bay. Bulletin of Marine Science 46:345-357. Comyns, B.H., C.F. Rakocinski, M.S. Peterson, and A.M. Shiller. 2008. Otolith chemistry of juvenile spotted seatrout Cynoscion nebulosus reflects local natal regions of coastal Mississippi, USA. Marine Ecology Progress Series 371:243-252. Gold, J R. and E.R. Richardson. 1998. Mitochondrial DNA di- versification and population structure in fishes from the Gulf of Mexico and western Atlantic. The Journal of Heredity 89:404-414. Gold, J.R., E.R. Richardson, and C. Eurman. 1999. Mitochondri- al DNA diversity and population structure of spotted seatrout (Cynoscion nebulosus) in coastal waters of the southeastern United States. Gulf of Mexico Science 17:40-50. GSMEC. 2001. The spotted seatrout fishery of the Gulf of Mexico, United States: a regional management plan. Publication No. 87. Gulf States Marine Eisheries Commission, Ocean Springs, MS, USA, 204 p. Haddon, M. 2001. Modeling and quantitative methods in fisher- ies. Chapman and Hall/CRC Press, Washington D.C., USA, 375 p. Hendon, J.R., J.R. Warren, J.S. Pranks, and M.V. Buchanan. 2002. Movements of spotted sea trout (Cynoscion nebulosus) in Missis- sippi coastal waters based on tag-recapture. Gulf of Mexico Science 2002:91-97. Hilborn, R. and C. Walters. 1992. Quantitative fisheries stock as- sessment: choice, dynamics, and uncertainty. Chapman and Hall, New York, NY, USA, 570 p. Hoff, A. and H. Prost. 2008. Modelling combined harvest and effort regulations: the case of the Dutch beam trawl fishery for plaice and sole in the North Sea. ICES Journal of Marine Science 65:822-831. Eegault, C., H.H. Stone, and K.J. Clark. 2006. Stock assessment of Georges Bank yellowtail flounder for 2006. NMPS North- east Eisheries Science Center TRAC Reference document - 2006/01, Woods Hole, MA, USA, 66 p. Moffett, AW. 1961. Movements and growth of spotted seatrout, Cynoscion nebulosus (Cuvier) in west Plorida. Marine Labora- tory, Institute of Marine Science of the University of Miami, Technical Series Number 36, Miami, PL,USA, 33 p. Mohr, L.C., M.P. Ebener, P. Brzuzan, P. Hliwa, and M. Luczynski. 2007. Evaluation of two harvest policies for managing lake whitefish (Coregonus clupeaformis) populations in a Laurentian Great Lake, Lake Huron. In: M. Jankus, ed. Schweizerbart' sche Verlagsbuchhandlung, Stuttgart Germany, p 471-483. Moncreiff, C.A., TA. Randall, and J.D. Caldwell. 1998. Mapping of seagrass resources in Mississippi Sound. Project Number BY3-156-3238. Pinal Report, Gulf Coast Research Laboratory, Ocean Springs, MS, USA, 33 p. NRC. 2006. Review of recreational fisheries survey methods. Na- tional Research Council, Washington, D.C., USA, 202 p. Reich, D.A. and J.T DeAlteris. 2009. A simulation study of the effects of spatially complex population structure for Gulf of Maine Atlantic cod. North American Journal of Eisheries Management 29:116-126. Rozas, E.R and TJ. Minello. 1998. Nekton use of salt marsh, seagrass, and nonvegetated habitats in a south Texas (USA) estuary. Bulletin of Marine Science 63:481-501. Schirripa, M.J., C.M. Eegault, and M. Ortiz. 1999. The red grou- per fishery of the Gulf of Mecxico: Assessment 3.0. Sustain- able Eisheries Division Contribution No. SPD-98/99-56. Technical Report. National Marine Eisheries Service, Wash- ington, D.C., USA, 58 p. 61 Gulf and Caribbean Research Volume 22 Issue 1 2010 Effects of Hurricane Katrina on an Incipient Population of Giant Salvinia Salvinia molesta in the Lower Pascagoula River^ Mississippi Pam L. Fuller U.S. Geological Survey Mike G. Pursley Mississippi Department of Marine Resources Dale Diaz Mississippi Department of Marine Resources Wesley Devers Mississippi Department of Marine Resourees DOI; 10.18785/gcr.2201.07 Follow this and additional works at: http:/ / aquila.usm.edu/ gcr & Part of the Marine Biology Commons Recommended Citation Fuller, P. L., M. G. Pursley, D. Diaz and W. Devers. 2010. Effects of Hurricane Katrina on an Incipient Population of Giant Salvinia Salvinia molesta in the Lower Pascagoula River, Mississippi. Gulf and Caribbean Research 22 (l): 63-66. Retrieved from http://aquila.usm.edu/gcr/vol22/issl/7 This Short Communication is brought to you for free and open access by The Aquila Digital Community. It has been accepted for inclusion in Gulf and Caribbean Research by an authorized editor of The Aquila Digital Community. For more information, please contact Joshua.Cromwell(®usm.edu. Gulf and Caribbean Research Vol 22, 63-66, 2010 Manuscript received August 14, 2009; accepted November 30, 2009 SHORT COMMUNICATION EFFECTS OF HURRICANE KATRINA ON AN INCIPIENT POPULATION OF GIANT SALVINIA SALVINIA MOLESTA IN THE LOWER PASCAGOULA RIVER, MISSISSIPPI Pam L. Fuller^*, Mike G. Pursley^, Dale Diaz^, and Wesley Devers^ ^US. Geological Survey, 1920 NW 7P^ Street, Gainesville, FL 32653 L7SA, ^Mississippi Department of Marine Resources, 1141 Bayview Avenue, Biloxi, MS 39530 USA * Gorresponding author, email: pfuller@usgs.gov Introduction Giant salvinia (Salvinia molesta) is among the worst inva- sive aquatic weeds in the world (Holm et al. 1977) and has invaded aquatic habitats in numerous countries (Julien et al. 2002). Under ideal conditions giant salvinia can double its biomass within 2 (Cary and Weerts 1983) to 4 d (Gau- det 1973, Mitchell and Tur 1975, Sale et al. 1985), clogging waterways with dense mats of vegetation. A single plant is capable of starting a population that may cover 103.6 km^ (40 mb) in 3 mo (Creagh 1991/1992 in Jacono and Pitman 2001). Giant salvinia can out-compete native vegetation and if control measures are not implemented, will completely cover the water surface and form mats up to 1 m thick (Cre- agh 1991/1992 in Oliver 1993). These mats deplete dissolved oxygen, make waterways uninhabitable by most fish species, impede boat traffic, reduce habitat for waterfowl, limit access for fishing and swimming and can interfere with water use for electrical generation, irrigation and municipal water sup- plies (Julien et al. 2002). Giant salvinia has been listed as a Federal Noxious Weed since 1984 (McFarland et al. 2004), and as such, it is ille- gal to import into, or transport this plant within the United States. Giant salvinia also appears on many state noxious weed lists, including Mississippi’s (U.S. Department of Ag- riculture 2009). However, if giant salvinia is not declared by a state as a noxious weed, it can still be cultivated and sold within that state. Despite regulations, this species continues to be moved through the water garden trade as an ornamen- tal plant for backyard ponds. Escapes or releases from such areas may have resulted in its establishment in numerous southern states such as Florida, Louisiana, and Texas and in major waterways like the Colorado River (U.S. Geological Survey 2009). A population of giant salvinia was discovered in June 2005 in the lower west Pascagoula River distributary and a major tributary. Bluff Creek, in Jackson County, Mississippi. At the first report of infestation, the Mississippi Department of Marine Resources (MDMR) conducted an initial survey of the watershed and determined that giant salvinia was restrict- ed to areas on the western side of the river both north and south of Interstate 10 and was densest in backwater sloughs (Figure 1). Biologists from MDMR also concluded that the infestation had become too extensive (about 789 ha) to erad- icate with herbicides or mechanical control methods, so Aus- tralian salvinia weevils (Cyrtobagous salviniae) were chosen as a bio -control agent. The weevils were seeded in 3 locations on 18 August 2005 in an effort to establish a population that would ultimately hinder the spread. An outreach campaign, in the form of signs at boat ramps and other high -visibility areas, was also initiated to increase public awareness of giant salvinia and on measures to prevent its spread. Interviews of local residents by MDMR indicate that the source of the infestation was likely a direct release of the plant during a clean-out of a water garden pond. The densest area of infes- tation was in a canal that drains a residential area just south of 1-10. Hurricane Katrina struck the Mississippi coast 29 August 2005 causing a storm surge in the study area ranging from 4.6-5.2 m (FEMA 2005). At the time, there was concern and speculation over the fate of the giant salvinia. Several hypoth- eses were considered to have merit: 1) The storm surge may have beached much of the plant material on land, rendering the population small enough for control efforts; 2) the salin- ity of the surge may have killed at least the downstream por- tion of the infestation; 3) the plant may have been spread to new areas during the flooding; and 4) the growth and spread of remaining giant salvinia may be augmented by increased nutrient levels resulting from the flooding. The objectives of this study were to: 1) survey the lower Pascagoula River Basin and determine the post-storm dis- tribution and abundance of giant salvinia; 2) control any remaining giant salvinia through physical and/or chemical means; 3) determine the fate of the bio-control agents; and 4) determine if re-introduction of salvinia weevils is needed and if so, to decide where best to release them. Materials and Methods The study area consisted of about 483 km of navigable waterway of the lower Pascagoula River system from near the river mouth at Highway 90 to about 11.26 km north of Inter- state 10 (Eigure 1). The extent of the survey area was chosen 63 Fuller et al. Figure J. Area of the lower Poscogoulo River, Jackson County, Mississippi surveyed for giant salvinia after Hurricane Katrina. The area encompassed by the white line is the pre- storm infestation area. Block dots are survey points with no giant salvinia; white dots ore areas where giant salvinia was found. White triangle (arrow) is Martin Bluff, where a population was found in June 2008. based on pre- Hurricane Katrina giant salvinia presence and was expanded well beyond known pre -storm distribution to determine if the invasive plant had infiltrated other water- ways. Because all records were destroyed when Hurricane Ka- trina flooded the MDMR offices, pre-storm giant salvinia distribution was approximated and was mapped based on the recollection of MDMR staff. Mapping surveys docu- mented the presence or absence of giant salvinia and oth- er aquatic invasive plants post Hurricane Katrina at about 3,300 points over 37 field days between 1 May and 9 August 2006. Monthly follow-up surveys have been conducted from September 2006 to the present to look for new infestations of giant salvinia. Bi-weekly surveys have been conducted to monitor giant salvinia growth and to spray and/or remove any remaining plants in previously identified areas. Initial mapping surveys were conducted using a 3 person crew. All crew members also served as invasive plant spotters to maximize detection probability. The speed of the survey boat was kept under 10 kph to facilitate observation of small fragments of gi- ant salvinia. A data point was created every 300 m. At each point, a Magellan Mobile Mapper CE using ArcPad 6.0 was used to record the presence or ab- sence of giant salvinia and the presence of any other aquatic invasive plants. Surface water temperature and salinity were acquired using a YSI model 556 multi-probe meter and manually en- tered into the Mobile Mapper as meta- data for each location. Digital photos were also taken of invasive plants when found. Survey crews also looked for the presence of salvinia weevils at each loca- tion by examining the plants for signs of weevil damage to the leaves. In areas with relatively small, isolated infesta- tions, the plants were removed from the water using a small screened net and secured for later disposal on land. At the end of each survey day, the boat was removed from the water and visu- ally checked for invasive plant matter on the outside and inside of the boat to prevent introduction of invasives into other waters. Follow-up surveys were less regi- mented and were performed by slowly cruising the area in a boat looking for areas with the plant. These surveys were combined with control spraying opera- tions. A mixture of 1.5% glyphosate and 0.5% diquat was applied on the remnants left by the storm every 10-14 d through October 2006, after which time no giant salvinia could be found. Monthly surveys of the formerly infested areas occasionally yielded small patches of giant salvinia from April 2007 to June 2008 in the canals north and south of I- 10. These areas were treated by mechanical removal and/ or herbicide appli- cation as noted above. Results The initial survey effort revealed that over 99% of the giant salvinia present prior to the storm was killed either by storm surge salinity or by being deposited on land. However, giant salvinia was found at 19 sites in 7 areas adjacent to the west Pascagoula River (Figure 1), totaling about 2 ha. Sur- prisingly, the infestation had not spread substantially. Only a few sites were located outside of the original area of infes- tation, and those were only a few meters from the original infestation. It was also surprising to learn that the surge did 64 Giant Salvinia in Pascagoula River not push the infestation farther upriver. The highest salin- ity where giant salvinia was found was 1.44, although Biber (2008) reported this species living in salinities of 7 in the lower Pascagoula River. Two new or previously unknown populations of the plant were located during follow-up surveys. One population of mature tertiary- stage growth was well-hidden in a patch of thick torpedo grass (Panicum repens) in a private pond com nected to the river by a culvert; the other was in a stand of emergent aquatic vegetation in a puddle at the very end of a silted -in canal. These plants were treated and eliminated. In June 2008, during a regular survey, a 46.45 m“ patch of rapidly reproducing young giant salvinia was found just north of Martin Bluff (Jackson County) adjacent to a large marshy area (Figure 1). No giant salvinia had been seen there since Hurricane Katrina. A few plants had been removed just south of this area in April 2006 and none were seen during subsequent surveys. Although it was thought that all the giant salvinia had been eliminated as of summer 2009, more patches have ap- peared, likely from hidden areas in the marsh that were not detected. No salvinia weevils were found during any of the surveys. Discussion An extensive river survey determined that the giant sah vinia population had been greatly reduced, rather than ex- panded, as a result of Hurricane Katrina. The reduction was attributed to deposition on land and mortality caused by exposure to salinity (see Biber 2008) during the storm surge. Evidence was found during the survey which may explain one way giant salvinia survived the storm surge. As water rose during Hurricane Katrina, giant salvinia was trapped in the framing of boat houses, which became completely submerged during the storm surge (Figure 2). As the water receded some of the giant salvinia likely fell from the framing and re -infested the area. After three years, there is still no evidence that any sah vinia weevils survived Hurricane Katrina. With most known infestations eliminated, weevil re-introduction is not practh cal, or advisable. The salvinia weevils would not have enough plant material to be sustained, and the giant salvinia they arrived on could cause a new outbreak. Mississippi Department of Marine Resources will contiiv ue conducting monthly boat and quarterly aerial surveys to look for new infestations and will survey the affected areas every 2 weeks. They will also continue public outreach efforts such as signs at boat ramps and brochures at fishing camps. Figure 2. Giant salvinia draped on rafters of a boot house along the Pascagoula River in the study area nearly a year after Hurricane Katrina. 65 Fuller et al. particularly in areas with close proximity to the infestations. The timing of this study was fortuitous as the remaining 2 ha of infestation could have easily exceeded the original 769 ha had no action been taken. The state was only able to respond because of the funding obtained for this study. Without a quick response, the infestation would have gotten out of control and become too large to manage. The small area of infestation was key in being able to effectively manage this population of giant salvinia. From the discovery in June 2005 until October 2009, MDMR estimates expenditures of over $256,000 on eciuipment, personnel, herbicides, and fuel and 2,110 person-hours to combat the invasion. Eradication of giant salvinia in all but small enclosed bod- ies of water has been deemed to be very unlikely, and even then will likely take years (McFarland et al. 2004). Given the size of the lower Pascagoula River, the complexity of its cham nels and emergent vegetation, and the fact that another pop- ulation of giant salvinia exists 235 km up-river in the Lower Leaf River (Robles et al. 2008), eradication seems unlikely in this area. However, because Hurricane Katrina reduced the population down to a manageable level, it appears that the state may be able to keep population levels low enough to control them in this area. Acknowledgements We would like to thank R. Flores and G. Larson for their help with field work. Aerial photographs used in the map were provided by the Mississippi Geospatial Clearing House. We are grateful to A. Benson for creating the map presented in the publication. Use of trade, product or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government. Funding provided by United States Geological Survey, Office of the Eastern Regional Executive for Biology, FY 2006 State Partnership Program. Literature Cited Biber, P.D. 2008. Determining salinity-tolerance of giant salvinia using chlorophyll fluorescence. Gulf and Caribbean Research 21 : 1 - 6 . Cary, PR. and PG.J. Weerts. 1983. Growth of Salvinia molesta as affected by water temperature and nutrition. 1. Effects of nitrogen level and nitrogen compounds. Aquatic Botany 16:163-172. Creagb, C. 1991/1992. A marauding weed in check. Ecos 70:26-29. FEMA. 2005. Mississippi Hurricane Katrina surge inunda- tion and advisory base flood elevation map panel overview. bttp://www. fema.gov/ pdf/bazard/ flood/ recoverydata/ ms_overview.pdf_(viewed on 10/19/2009). Gaudet, J.J. 1973. Growth of a floating aquatic weed, Salvinia, under standard conditions. Hydrobiologia 41:77-106. Holm, L.G., D.L. Plucknett, J.V. Pancbo, and J.R Herberger. 1977. Tbe World’s Worst Weeds. University Press of Hawaii, Honolulu, HI, USA, 609 p. Jacono, C. and B. Pitman. 2001. Salvinia molesta: Around tbe world in 70 years. Aquatic Nuisance Species Digest 4:14-16. Julien, M.H., TD. Center, and RW. Tipping. 2002. Floating Fern (Salvinia). In: R.V. Van Driescbe, S. Lyon, B. Blossey, M. Hoddle, and R. Reardon, tecbnical coordinators. Biological Control of Invasive Plants in tbe Eastern United States. Pub- lication FHTET-2002-04, USDA Forest Service, Morgan- town, WV, USA. 413 p. McFarland, D.G., L.S. Nelson, M.J. Grodowitz, R.M. Smart, and C.S. Owens. 2004. Salvinia molesta D.S. Mitcbell (Giant Salvinia) in the United States: A Review of Species Ecology and Approaches to Management. Technical Report DRDC/ EL SR-0402. U.S. Army Corps of Engineers, Engineer Re- search and Development Center, Environmental Laboratory, Vicksburg, MS, USA. 41 p. Mitchell, D.S. and N.M. Tur. 1975. The rate of growth of Salvinia molesta [S. auriculata Auct.] in laboratory and natural condi- tions. Journal of Applied Ecology 12:213-225. Oliver, J.D. 1993. A review of the biology of giant salvinia (Sal- vinia molesta Mitchell). Journal of Aquatic Plant Management 31:227-231. Robles, W., J.D. Madsen, V.L. Maddox, and R.M. Wersal. 2008. 2007 statewide survey of the status of giant salvinia and hy- drilla in Mississippi. GeoReferences Instittite Report #5019. Technical Report. Mississippi Bureau of Plant Industry, GeoReferences Institute and Department of Plant and Soil Sciences. Mississippi State University, Mississippi State, MS, USA. 11 p. Available from: bttp://www.gri.msstate.edu/pub- lications/docs/2008/02/3739GRI_5019_2008.pdf (viewed on 11/30/2009). Sale, P.J.M., P.T Orr, G.S. Shell, and D.J.C. Erskine. 1985. Pho- tosynthesis and growth rates in Salvinia molesta and Eichhornia crassipes. Journal of Applied Ecology 22:125-137. U.S. Department of Agriculture. 2009. Mississippi State-listed noxious weeds. PLANTS database. bttp://plants.usda. gov/java/noxious?rptType=State&cstatefips=28 (viewed on 10/19/2009). U.S. Geological Survey. 2009. Nonindigenous Aciuatic Species Database. Gainesville, FL. http://nas.er.usgs.gov. (viewed on 8/15/2009) 66 Gulf and Caribbean Research Volume 22 Issue 1 2010 Notes on the Biology of an Adult Female Chimaera cubana Captured Off St. Croix^ US. Virgin Islands William B. Driggers III National Marine Fisheries Service^ Pascagoula, william.driggers(®noaa.gov Jill M. Hendon University of Southern Mississippi Michael J. Andres University of Southern Mississippi Stephen S. Curran University of Southern Mississippi Christopher T. Gledhill National Marine Fisheries Service, Pascagoula et al DOI; 10.18785/gcr.2201.08 Follow this and additional works at; http://aquila.usm.edu/gcr & Part of the Marine Biology Commons Recommended Citation DriggerS; W. B. Ill, J. M. Hendon, M. J. Andres, S. S. Curran, C. T. Gledhill, M. A. Grace, M. D. Hendon, C. M. Jones, B. T. Noble and K. R. Rademacher. 2010. Notes on the Biology of an Adult Female Chimaera cubana Captured Off St. Croix, U.S. Virgin Islands. Gulf and Caribbean Research 22 (l): 67-69. Retrieved from http:// aquila.usm.edu/gcr/vol22/iss 1/8 This Short Communication is brought to you for free and open access by The Aquila Digital Community. It has been accepted for inclusion in Gulf and Caribbean Research by an authorized editor of The Aquila Digital Community For more information, please contact Joshua.Cromwell^usm.edu. Gulf and Caribbean Research Vol 22, 67-69, 2010 Manuscript received August 12, 2009; accepted December 2, 2009 SHORT COMMUNICATION NOTES ON THE BIOLOGY OF AN ADULT FEMALE CHIA/IAERA CUBANA CAPTURED OFF ST. CROIX, U.S. VIRGIN ISLANDS William B. Driggers, 111 Jill M. Hendon^ Michael J. Andres^ Stephen S. Curran^ Christopher T. Gledhilh, Mark A. Graceh Michael D. Hendonh Christian M. JonesS Brandi T. Nohleh and Kevin R. Rademacher^ ^National Marine Fisheries Service, Southeast Fisheries Science Center, Mississippi Laboratories, P.O. Drawer 1207, Pascagoula, MS 39567, ^The University of Southern Mississippi, Gulf Coast Research Laboratory, 703 East Beach Drive, Ocean Springs, MS 39564 * Corresponding author, e-mail: william.driggers@noaa.gov Introduction Within the western North Atlantic Ocean there are at least 4 genera and 5 species of chimaeroids occurring in deep waters generally associated with outer continental slopes or areas of high bathymetric relief (Didier 2002; Didier 2004). Two chimaeroids, Chimaera cubana and Hydrolagus alberti, are known to be indigenous to the Caribbean Sea in waters asso- ciated with the Greater and Lesser Antilles. While H. alberti occurs throughout the Gulf of Mexico and the Caribbean Sea, C. cubana is thought to be endemic to an area bounded by Cuba and Colombia (lUCN 2009). These two chimaeras are readily differentiated by the presence or absence of an anal fin and species-specific branching patterns of cranial lateral line canals (Didier 2004). Since the description of C. cubana by Howell-Rivero (1936), only 10 specimens have been reported in the primary literature with another 11 speck mens located in museum collections (Bunkley- Williams and Williams 2004). The dearth of biological information on C. cubana led the International Union for the Conservation of Nature to recommend that “basic data be collected on all captures” (lUCN 2009). Figure 1. Lateral view of the adult female Chimaera cubana col- lected south of St. Croix, U.S. Virgin Islands, on 25 March 2009. The right side of the fish is presented due to damage to the left pec- toral and pelvic fins. Note that the preoperculor and horizontal canals hove separate branching points from the suborbital canal. Materials and Methods On 25 March 2009 an adult female C. cubana was cap- tured on longline gear off St. Croix, U.S. Virgin Islands, at 17A8.25’N, 64“48.26W betvs^een 2017-2144 h at a depth of 280 m. The bottom temperature, dissolved oxygen and saliiv ity at the site were 18.3“C, 5.7 mg/1 and 36.5, respectively. An incision was made through the abdominal musculature and the gastrointestinal and reproductive organs were ex- cised. Fresh material was used for all examinations and pho- tographs. The specimen was frozen after inspection, and later deposited in the museum at the University of Southern Mis- sissippi. Gulf Coast Research Laboratory (accession number GCRL 36376). Anatomical terms used in descriptions follow Dean (1906), Wourms (1977) and Jones et al. (2005). Results and Discussion The specimen’s anal fin, caudal fin and tail filament were missing (Figure 1), and thus a total length measurement was not taken. The distances from the snout to the pectoral fin origin and snout to the pelvic fin origin were 103 mm and 338 mm, respectively. The digestive tract contained numerous Clypcastcr subdc- prcssus tests and ambulatory spines, suggesting these echino- derms could represent a significant prey item of C. cubana. Eight gyrocotylidean cestodes were distributed throughout the spiral intestine. Bunkley- Williams and Williams (2004) reported the presence of 2 specimens of a gyrocotylidean cestode in the spiral intestine of a C. cubana caught off La Parguera, Puerto Rico, and identified the specimens as Gy- rocotylc rugosa or G. urna. We obtained the specimens re- ported by Bunkley- Williams and Williams (2004) from the United States National Parasite Collection (USNPC No. 92730) and found them to be conspecific with the specimens we collected. Based on diagnostic characters used to differ- entiate among the species within the genus (i.e., shape of the lateral body margin), we identified all of the specimens as G. urna. A forthcoming study will examine 28S rDNA fragments from the Caribbean, Norwegian and Australian specimens of G. urna to thoroughly assess the identity of Ca- ribbean Gyrocotylc fauna. The reproductive tract was typical of a female chimaeroid 67 Driggers et al. 10 cm Figure 2, Reproductive tract of the adult female Chimaera cu- bana collected south of St. Croix, U.S. Virgin Islands on 25 March 2009. Note vitellogenic follicles in varying stages of develop- ment. oo = anterior oviduct, o = ostium, og = oviducol gland, po = posterior oviduct, sr = seminal receptacle, vf = vitellogenic follicle. (Dean 1906; Figure 2). No oocytes or developing egg cases were present within either oviducal gland. Fifty-eight foF licles were visible in the 2 ovaries and no corpora lutea were observed. Non-vitellogenic follicles ranged in diameter from 1 to 7 mm (mean = 3.65; sd = 1.96). Vitellogenic foF licles ranged in diameter from 9 to 35 mm (mean = 17.58; sd. = 9.96) and appeared to be separable into 6 size cohorts (Figure 3). The follicle pair of greatest diameter were in the right ovary and consisted of 2 follicles with diameters of 35 and 32 mm. The next largest cohort was in the left ovary with follicle diameters of 26 and 25 mm. Cohort 3 was in the right ovary and consisted of a single 21 mm follicle. The remaining cohorts continued to show a pattern of decreasing diameters in alternating ovaries. To our knowledge, this is the first report of oocytes maturing in ovary- specific series for any chondrichthyan. The presence of oocytes in various stages of development strongly suggests that C. cubana is reproductively active over a relatively protracted period and is consistent with the re- productive biology of other chimaeroids, such as Callorhyncus callorhyncus and Hydrolagus colliei (DiGiacomo and Raquel Perier 1994, Barnett et al. 2009). The absence of corpora lutea in the ovaries or egg case development in the ovidu- cal glands or posterior oviducts suggests the specimen had not recently ovulated. Therefore, the number of vitellogenic follicles present in the ovaries indicates that the C. cubana we collected was capable of an annual fecundity of at least 12 young, assuming all vitellogenic oocytes eventually be- came fertilized, encased and deposited. In the absence of additional data on the reproductive biology of this species we must assume this is an estimate of maximum fecundity. It is likely, however, that the maximum annual fecundity is higher since vitellogenesis appears to be relatively rapid, as indicated by follicles of varying sizes and the simultaneous presence of vitellogenic and noiwitellogenic follicles. Figure 3 . Ovarian follicle di- ameter and oocyte cohort as- signment as observed in an adult female Chimaera cubana collect- ed south of St. Croix, U.S. Virgin Islands on 25 March 2009. All oocytes in cohort 7 were non- vitellogenic. □ = right ovarian follicle diameter, X = left ovarian follicle diameter. Biology of Chimaera Cubana Acknowledgements We thank the crew of the NOAA Ship Oregon II for assistance in collection of the specimen. Literature Cited Barnett, LA., R.L Earley, D.A. Ebert, and G.M. Cailliet. 2009. Maturity, fecundity, and reproductive cycle of die spotted ratfish, Hydrolagus colliei. Marine Biology 156:301-316. Bunkley- Williams, L.B. and E.H. Williams. 2004. New locality, depth, and size records and species character modifications of some Caribbean deep-reef/ shallow slope fisbes and a new bost and locality record for cbimaera cestodarian. Caribbean Journal of Science 40:88-119. Dean, B. 1906. Cbimaeroid fishes and their development. Car- negie Institution of Washington, Washington, D.C., USA, 194 p. Di Ciacomo, E.E. and M. Raquel Perier. 1994. Reproductive biology of the cockfish, Callorhynchus callorhynchus (Holo- cepbali: Callorbyncbidae), in Patagonian waters (Argentina). Eisberies Bulletin 92:531-539. Didier, D.A. 2002. Cbimaeras. In: K.E. Carpenter, ed. The Eiving Marine resources of the Western Central Atlantic. Volume 1: Introduction, Molluscs, Crustaceans, Hagfishes, Sharks, Batoid Eishes and Chimaeras. EAO Species Identi- fication Cuide for Eishery Purposes and American Society of Ichthyologists and Herpetologists Special Publication No. 5. Pood and Agricultural Organization, Rome, Italy, p. 591-599. Didier, D.A. 2004. Phylogeny and classification of extant bolo- cepbali. In: J.C. Carrier, J.A. Musick, and M.R. Heitbaus, eds. Biology of Sharks and Their Relatives. CRC Press, Boca Raton, PL, USA, p. 115-135. Howell-Rivero, L. 1936. Some new rare and little known fishes from Cuba. Proceedings of the Boston Society of Natural History 41:41-76. lUCN. 2009. The lUCN Red List of Threatened Species: Chimaera cubana. http://www.iucnredlist.org (viewed on 4/22/2009). Jones, C.J.P., T.I. Walker, J.D. Bell, M.B. Reardon, C.E. Ambro- sio, A. Almeida, and W.C. Hamlett. 2005. Male genital ducts and copulatory appendages in cbondricbthyans. In: W.C. Hamlett, ed. Reproductive Biology and Phylogeny of Chondrichtbyes. Science Publishers, Inc., Enfield, NH, USA, p. 361-393. Wourms, J.P. 1977. Reproduction and development in chon- drichthy an fishes. American Zoologist 17:379-410. 69 Gulf and Caribbean Research Volume 22 Issue 1 2010 Growth Patterns of Shoal Grass Halodule wrightii and Manatee Grass Syringodiumjiliforme in the Western Gulf of Mexico Melissa A. Gutierrez Texas A&M Universityj Corpus Christi Annette A. Cardona Texas A6’M University, Corpus Christi Delbert L. Smee Texas A&M University, Corpus Christi, lee.smee^tamucc.edu DOI; 10.18785/gcr.2201.09 Follow this and additional works at: http:/ / aquila.usm.edu/ gcr & Part of the Marine Biology Commons Recommended Citation Gutierrez, M. A., A. A. Cardona and D. L. Smee. 2010. Growth Patterns of Shoal Grass Halodule wrightii and Manatee Grass Syringodiumjiliforme in the Western Gulf of Mexico. Gulf and Caribbean Research 22 (l): 71-75. Retrieved from http : / / aquila.usm.edu/ gcr/ vol22/ iss 1 /9 This Short Communication is brought to you for free and open access by The Aquila Digital Community. It has been accepted for inclusion in Gulf and Caribbean Research by an authorized editor of The Aquila Digital Community. For more information, please contact Joshua.Cromwell(®usm.edu. Gulf and Caribbean Research Vol 22, 71-75, 2010 Manuscript received October 30, 2009; accepted December 15, 2009 SHORT COMMUNICATION GROWTH PATTERNS OF SHOAL GRASS HALODULE WRIGHTU AND MANATEE GRASS SYRINGODIUM FILIFORME IN THE WESTERN GULF OF MEXICO Melissa A. Gutierrez, Annette A. Cardona, and Delbert L. Smee* Texas A&M University - Corpus Christi, Department of Life Sciences, 6300 Ocean Dr. Unit 5800, Corpus Christi, TX 78412 * Corresponding author, entail: lee.smee@tamucc.edu Introduction Seagrass beds are a valuable resource because of the numer- ous roles they play in coastal systems. Seagrass blades provide habitat for abundant micro- and macro -algal communities, which in conjunction with the seagrass, contribute substam tially to primary productivity in estuarine systems (Heck and Valentine 2006). The blades and roots stabilize sediments, which improves water clarity and increases light penetration, further increasing primary production (Zieman 1982, Gacia and Duarte 2001). Seagrass beds may also provide increased growth rates, critical habitat, and predation refuges for a vari- ety of organisms (e.g., Irlandi and Peterson 1991, Hemminga and Duarte 2000) and have an increased abundance and dh versity of juvenile and adult fish and other epibenthic organ- isms (Summerson and Peterson 1984, Heck et al. 1995). In Texas, like most of the western Gulf of Mexico (GOM), shoal grass (Halodule wrightii), manatee grass (Syrin^ godium filiforme), and turtle grass (Thalassia testudinum) are the most common seagrasses (Zieman 1982, Quammen and Onuf 1993, Withers 2002). Eighty percent of seagrass beds in Texas currently occur in the Laguna Madre (hereafter LM), a hypersaline lagoon that separates a coastal barrier island (Padre Island) from the Texas mainland (Piilich 1998, Tunnell and Judd 2002). Seagrasses were once common in many Texas bays, but have disappeared or declined in coverage in many areas due to anthropogenic causes (Pu- lich and Onuf 2007). Fortunately, the loss of seagrasses in Texas bays was offset by the increase in seagrass abun- dance in the LM due to the moderation of salinity after dredging of the Gulf Intracoastal Waterway (Quammen and Onuf 1993). Shoal grass can survive and grow in sa- linities from 5-80 (McMillan and Moseley 1967) and this seagrass dominated the LM for decades because of its abil- ity to withstand these extreme salinities (Withers 2002). Shoal grass harbors a diverse resident fauna (Tolan et al. 1997) and the migratory redhead duck (Aythya ameri- cana) population depends on shoal grass in the LM for food during the winter season (Cornelius 1977). Shoal and manatee grass are currently present in the upper LM, with shoal grass historically being dominant (Quammen and Onuf 1993) and extensively studied (e.g., Dunton 1994, 1996). However, manatee grass is increasing in coverage in much of the LM and is steadily replacing shoal grass in this system (Quammen and Onuf 1993, Pulich and Onuf 2007). In other areas such as Corpus Christi Bay, shoal, manatee, and turtle grass have coexisted for the past 20 yrs (Czerny and Dunton 1995, K. Dunton pers. comm.). Although manatee grass is becoming increasingly abun- dant in Texas bays, its growth characteristics have not been measured in the western GOM. Changes in seagrass species composition can have significant community ef- fects (Micheli et al. 2008), but the effects of a transition from shoal to manatee grass in the LM have not been ex- tensively studied (but see Tolan et al. 1997). The goals of our study were to measure growth patterns of these two seagrass species in tw^o locations in the western GOM that vary in salinity, epiphyte loads, and nutrient inputs. Materials and Methods We selected two locations (bays) for this study: the East Flats section of Corpus Christi Bay (CCB) and another in the upper LM. Corpus Christi Bay is an urban estuary that receives substantial nutrient inputs, which are much higher than in the LM. Water exchange occurs more read- ily in CCB, giving this location lower, albeit more variable, salinity. By utilizing these locations, we were able to measure growth characteristics of shoal and manatee grass under dif- ferent abiotic conditions. In both CCB and LM, we sampled monospecific stands of manatee grass that were adjacent to monospecific stands of shoal grass. Seagrass beds were sepa- rated by ~50 m in LM and ~500 m in CCB, and all were lo- cated in about 1.3 m of water (referenced to MLLW). GPS co- ordinates were 27°24.793’N, 97°21.224W (shoal grass) and 27°24.805’N, 97°21.214’W (manatee grass) in the LM and 27°48.58rN, 97°07.323’W (shoal grass) and 27°48.758’N, 97°07.195’W (manatee grass) in CCB. We placed a PVC pole near the center of each seagrass bed and all growth character- istics were made within 10 m of these poles for each species. Hydrolab minisondes were deployed in both loca- tions and set to measure salinity and water tempera- ture over a 60 s period daily for 10-14 d. We averaged the salinity and temperature for each 60 s measurement and then averaged these values for a grand mean of 71 Gutierrez et al. temperature and salinity for each deployment period We quantified epiphyte load on shoal and manatee grass in both locations in June 2007 when epiphytes were abun- dant, as epiphytes can strongly influence seagrass growth and mortality (Burd and Dunton 2001, Duarte 2002, Lir- man and Cropper 2003). Our methods consisted of taking 5 randomly sampled, 10 cm diameter core samples using a polyvinyl chloride (PVC) corer (Johnson and Heck 2006) from each seagrass type. Within each core sample, 3 seagrass shoots were randomly selected for epiphyte quantification. The blade surface area was standardized by only using the old- est 10 cm of growth (top of the grass) with no obvious signs of grazing or other damage. We then carefully scraped off the epiphytes with a scalpel and transferred them to pre-weighed (0.001 g) Whatman GF/C filter paper. The filter paper and epiphytes were dried in a convection oven and weighed (0.001 g), and the total weight was subtracted from the original fil- ter paper weight to quantify the epiphyte load. The epiphyte weight of the 3 blades was averaged to produce one epiphyte value per core sample. This produced 5 samples of epi- phyte weight per location for both shoal and manatee grass. We sampled seagrass growth characteristics during con- secutive peak growing seasons from March 2007 through June 2008. Sampling was conducted every 10-28 d (n = 27 dates) depending on the season and weather conditions. We measured shoot density, root:shoot ratio (RSR), and pri- mary growth rate in each location to determine the annual mean primary productivity patterns for each seagrass spe- cies. We also measured the density of reproductive shoots produced by manatee grass in each location. Daily varia- tion in temperature and salinity are less likely to influence seagrass growth patterns than longer term differences (Dun- ton 1990, 1994), thus we pooled our data over date to fo- cus specifically on comparing only seagrass growth patterns. To measure primary growth, we used the clipping tech- nique of Virnstein (1982); however, due to turbidity, we “harvested” the samples rather than photographing growth (Dunton 1990). This technique consisted of haphazardly selecting and trimming 0.25 iW plots (n = 3) of shoal grass and 0.25 m^ plots (n = 3) of manatee grass in each loca- tion on each sampling date. Cuts were made 1.0 cm above the basal sheath for shoal grass, which allowed us to sample continuous growth (Dunton 1994). For manatee grass, cuts were made 6 . 0 - 1. 0 cm above the basal sheath as preliminary results indicate that clipping below this height resulted in blade death. On each sampling date, a 10.0 cm diameter core sample, ^ 10.0 cm deep, was taken from each newly clipped plot as well as from each plot that had been clipped on the previous sampling date. Ten blades from the sample of the newly clipped plot were measured and averaged to determine the mean cut length at time 0 (i.e., mean blade length above substrate after clipping). The length of every blade was measured from the second core, which was taken 10-28 d after clipping. The mean cut length calculated im- mediately after clipping was subtracted from the mean total length in the second core to determine the amount of growth in each of the 3 plots sampled. Growth rate (cm/ d) was cal- culated by dividing the mean growth rate by the number of days bem^een clipping and harvesting. The growth rates cal- culated for each core sample were averaged to calculate the grand mean growth rates for each grass by location and date. We also measured shoot density (#/ m^) by collecting 78.5 cm^ core samples (n = 3) from an area outside our clipped plot, counting the shoots in each core, and multiplying by 127.4 to convert the value to m^. We pooled our density measurements from each core sample to calculate a mean density for each species by location and then averaged these mean density measures by date (n = 27) to calculate a grand mean for shoal and manatee grass in each location To determine RSR, aboveground biomass (blades, g) and underground biomass (roots and rhizomes, g) were mea- sured from shoal grass and manatee grass beds in each loca- tion during each sampling date (n = 27). Three random core samples (78.5 cm^, 10.0 cm diameter) were taken to a depth of ~ 15.0 cm to ensure the collection of all root and rhizome structures. We haphazardly removed 10 blades from each core sample that had rhizomes attached, divided them into above and below ground sections, and scraped off any epi- phytic material from the above ground portion. Above and below ground sections were dried separately in a convection oven at 60°C for 96 h and individually weighed from each Figure I. Monthly water quality measurements in each location (boy) during the study A. Temperature (mean ± sd). B. Salinity (mean ± sd). The variability within each measurement period was low and using se resulted in the error bars being obscured by the data points. Growth Patterns of Seogrosses 0.009 £ 0.006 O) I Q. >« Q. 0.003 Q. LU 0 ■ Corpus Christi Bay □ Laguna Mad re * Shoal Grass Figure 2. Plot of epiphyte weight (g; mean + se) on shool and manatee grass (n = 5) from both locations (bays). * - significant difference between locations. core sample to calculate the RSR for each blade. Mean RSRs were calculated by species in each location by date (n = 27). A grand mean RSR was calculated for each seagrass species in each bay by averaging the RSR values from all sampling dates. We also counted the number of reproductive shoots in the RSR core samples collected in manatee grass beds on 6 sampling dates between March and May in 2007 and 5 sampling dates bet\^^een March and May 2008. This was done because a high number of reproductive shoots may suggest lateral growth that would not be apparent from a ‘clip and harvest’ measurement. Shoal grass reproductive shoots were not observed during the study. As with shoot density, we multiplied the number of reproductive shoots by 127.4 to convert this value to number per mL Since we took 3 core samples on each sampling date, the number of reproductive shoots in each core sample was averaged. Data analysis We compared the grand mean of temperature and salinity between CCB and LM with a Student t-test (Sokal and Rohlf 1995). We then compared grand mean density, grand mean growth rates and grand mean RSR for each seagrass species between locations with a Student t-test (Sokal and Rohlf 1995). We compared the mean number of shoots pooled by date (n = 6 in 2007 and n = 5 in 2008) betw^een locations by year with separate Mann-Whitney U tests because our data did not meet t-test assumptions (Sokal and Rohlf 1995). LM was 34.0 and ranged between 28.0-38.5 as compared to CCB with a mean salinity of 24.7 (range 20.3-28.8). Epiphyte weight on shoal grass was significantly (32x) greater in CCB than in LM (t = 3.18, p < 0.05, n = 5, Figure 2). Similarly, the epiphyte weight recovered from manatee grass was significantly (9x) greater in CCB than in LM (t = 3.30, p < 0.05, n = 5, Figure 2). Previous research revealed that nutrient inputs are much greater in CCB than in LM (Quammen and Onuf 1993, Lee and Dunton 2000) and higher ambient nutrient levels are most likely responsible for the greater epiphyte weight measured in this study. Shoal grass shoot density was significantly higher and more variable in the LM (t = 2.94, p < 0.01, Table 1). Shoal grass shoot density peaked in LM in March 2008, reaching a density of ~7000 shoots/mk In CCB, shoal grass density peaked at -3600 shoots/iW in May of 2008. Shoot density was lowest in LM with ~470 shoots/ m^ in October 2007 and CCB had its lowest density of ^ 850 shoots/ m^ in November of 2007. Manatee grass shoot density was also greater and more variable in LM (Table 1). A t-test revealed statistical differences between the shoot densities of manatee grass be- t\A^een locations (t = 3.18, p < 0 .01, Table 1). The LM reached its peak density of ^4000 shoots/m^ in May 2007 and CCB density peaked at ~2100 shoots/m^ in June 2007. The low- est density observed was ^420 shoots/m^ in CCB in Octo- her 2007 and ~540 shoots/m^ in LM in November 2007. 1 0000 1 2007 2008 Figure 3. Plot of number of reproductive shoots (mean + se) pro- duced by manatee grass from March to May 2007 (n = 6) and March to May 2008 (n = 5) in Corpus Christi Bay and the Laguna Madre. * - significant difference between locations. Results and Discussion Temporal measurements of water temperature and saliiv ity are presented in Figure 1 to illustrate seasonal trends. However, statistical analysis was performed only on the grand mean values (n = 13) between locations. Water tern- perature ranged from 13.7°-29.9°C and was not statis- tically different between the LM and CCB (t = 0.18, p = 0.85, Figure lA). Salinity was significantly higher in LM (t = 4.46, p < 0.01, Figure IB). The mean salinity in the Root:shoot ratios determine seasonal differences be- tween the aboveground and belowground biomass fractions of seagrass, reflecting seagrass energy allocation (Dunton 1994, 1996). Higher ratios occur during the winter season when plants are dormant and are allocating more energy into roots and other below ground structures, but ratios decrease when energy is allocated toward above ground growth in the spring and summer. The RSR ratios ranged from 1.05-4.9 in shoal grass and 0.44-2.56 in manatee 73 Gutierrez et al. TABLE I. Grand mean growth characteristics ± se (range of values in parentheses) of shoal and manatee gross in two Texas boys. Grand means were calculated from the means of 27 sampling events of monospecific stands of shoal gross and manatee grass in Corpus Christi Bay, TX and the Laguna Madre Texas. * - significant difference between locations. Growth Parameter Shoal Gross Corpus Christi Boy Laguna Madre Manatee Grass Corpus Christi Bay Laguna Madre Shoot Density (number/m^) RootiShoot Ratio (RSR) Growth Rote (cm/doy) 2274 ± 439 (854-3605) 2.25 ±0.37 (1.05-4.90) 0.41 ±0.06 (0.07-0.80)* 3347 ±555 (471-6969)* 2.13 ±0.23 (1.08-4.2) 0.27 ±0.05 (0.07-0.87) 1254 ±281 (420-21 28) 1.1 7 ±0.1 9 (0.44-2.56) 0.52 ±0.14 (0.060-01.2) 1774 ±(548-3965)* 1.28 ±0.21 (0.49-2.13) 0.41 ±0.11 (0.04-1.1) grass (Table 1). Ratios were not significantly different be- tw^een CCB and LM for either shoal grass (t = 0.05, p = 0.61, Table 1) or manatee grass (t = 0.93, p = 0.35, Table 1). Shoal grass grew significantly faster in CCB (t = 2.68, p < 0.05, Table 1). Annual mean growth rates for shoal grass were 0.41 cm/ d and 0.27 cm/ d in CCB and LM, respectively. In both locations, the period of slowest growth occurreci in January 2008 and was calculated in both at 0.07 cm/ d. Shoal grass peak growth of 0.87 cm/ d occurred in LM in September 2007, while growth peaked at 0.81 cm/ d in CCB in July 2007. Manatee grass grew faster in CCB with an annual mean rate of 0.52 cm/d as compared to 0.43 cm/d in LM, but these rates were not statistically different (t = 1.13, p = 0.23, Table 1). Peak growth rate of 1.11 cm/d occurred in LM in June 2007, while the least growth of 0.05 cm/d occurred in March 2007. Peak growth rates of 1.20 cm/d occurred in CCB in August 2007, while the slowest growth in CCB was 0.06 cm/d in January 2008. Shoal grass reproductive shoots were not observed dun ing the study. Manatee grass produced a significantly high- er number of reproductive shoots in LM (-875 reproduc- tive shoots/m^) as compared to CCB (-85 reproductive shoots/m^, z = 2.16, p < 0.05, Figure 3) from March to May 2007. Numbers of reproductive shoots were not sig- nificantly different from March to May 2008 (z = 0.63, p = 0.73, Figure 4) with -41 shoots/m^ at both locations. Because manatee grass has historically been much less common than other seagrasses in Texas (Quammen and Onuf 1993), its seasonal growth patterns in the field have not been carefully studied in this region. Our study pro- vides the first documentation of manatee grass growth and energy allocation patterns in the western COM. Our estF mates of shoal grass growth and RSR ratios are consistent with earlier measurements made by Dunton (1990, 1994, 1996), suggesting that our technique provided an appro- priate assessment of primary production of both species. Our study locations are exhibiting different patterns of seagrass succession. Seagrass succession in the LM is follow- ing the traditional model proposed by Zieman (1982) where shoal grass, the pioneer species, is replaced by manatee grass and finally by turtle grass, the climax community (Quam- men and Onuf 1993, Pulich and Onuf 2007). In contrast, all three seagrasses have coexisted for the past 20 yr in CCB without an obvious loss in overall coverage of any one spe- cies (Czerny and Dunton 1995, K. Dunton pers. comm.). Fluctuations in salinity can be stressful to seagrasses and slow or stop succession so that multiple species co- exist (Montague and Ley 1993). Salinity fluctuations in CCB, coupled with higher epiphyte loads, may act like moderate disturbances, thus stalling seagrass succession and promoting coexistence of these species. Conversely, the more constant salinity levels and lower epiphyte loads in LM are allowing succession to proceed with manatee grass slowly replacing shoal grass. Both seagrasses grew faster in CCB and had higher epiphyte loads, which were likely caused by greater nutrient inputs at this location. We observed higher shoot density in both seagrasses as well as greater energy allocation to lateral growth and reproduc- tive structures by manatee grass in LM, suggesting that condi- tions in this location are more favorable for seagrasses than in CCB. Should seagrass succession proceed in LM, a significant change in species composition in this important and unique ecosystem will likely occur. We must continue to monitor changes in seagrass composition in Texas to better understand potential consequences of species replacement. Since seagrass composition strongly influences community structure (Tolan et al. 1997, Micheli et al. 2008), it is necessary to understand the mechanisms driving seagrass change especially with the current decline in seagrasses worldwide. This study pro- vides important baseline information to begin this process. Acknowledgements We would like to extend our most sincere appreciation to the members of the Marine Ecology Lab at TAMU-CC, particularly K. Johnson, for help in the field. Important methodological advice was pro- vided by K. Jackson (UTMSl). Roy Lehman, K. Dunton, M. Johnson, N. Brown -Peterson, M.S. Peter- son, and two anonymous reviewers provided comments that improved the manuscript. Funding support was provided by grants from NSF-OCE #0648433 and the Texas Research Development Fund to D. Smee. 74 Growth Patterns of Seogrosses Literature Cited Burd, A.B. and K.H. Dunton. 2001. Field verification of a light' driven model of biomass changes in the seagrass Halodule 'wrightii. Marine Ecology Progress Series 209:85-98. Czerny, A.B. and K.H. Dunton. 1995. The effects of in situ light reduction on the growth of two subtropical seagrasses, Thalas- sia testudinum and Halodule wrightii. Estuaries 18:418-427. Cornelius, S.E. 1977. Food and resource utilization by winter- ing redheads on lower Laguna Madre. Journal of Wildlife Management 41:374-85. Duarte, C.M. 2002. The future of seagrass meadows. Environmen- tal Conservation 29:192-206. Dunton, K.H. 1990. Production ecology of Ruppia maritima L. s.l. and Halodule wrightii Aschers in two subtropical estuar- ies. Journal of Experimental Marine Biology and Ecology 143:147-164. Dunton, K.H. 1994. Seasonal growth and biomass of the subtropi- cal Halodule wrightii in relation to continuous measurements of underwater irradiance. Marine Biology 120:479-489. Dunton, K.H. 1996. Photosynthetic production and biomass of the subtropical seagrass Halodule wrightii along an estuarine gradient. Estuaries 19:436—447. Gacia, E. and C.M. Duarte. 2001. Sediment retention by a Medi- terranean Posidonia oceanica meadow: the balance between de- position and new suspension. Estuarine, Coastal and Shelf Science 52:505-514. Heck, K.L. Jr. and J.E. Valentine. 2006. Plant-herbivore interac- tions in seagrass meadows. Journal of Experimental Marine Biology and Ecology 330:420-436. Heck, K.L. Jr., K.W. Able, C.T Roman, and M.P. Eahay. 1995. Composition, abundance, biomass and production of macro- fauna in a New England estuary: comparisons among eelgrass meadows and other nursery habitats. Estuaries 18:379-389. Hemminga, M.A. and C.M. Duarte. 2000. Seagrass Ecology. Cam- bridge University Press, New York, NY, USA, 298 p. Irlandi, E.A. and C.H. Peterson. 1991. Modification of animal habitat by large plants: Mechanisms by which seagrasses influ- ence clam growth. Oecologia 87:307-318. Johnson, M.W. and K.L. Heck. 2006. Effects of habitat fragmenta- tion per se on decapods and fishes inhabiting seagrass mead- ows in the Northern Gulf of Mexico. Marine Ecology Progress Series 306:233-246. Lee, K.S. and K.H. Dunton. 2000. Effects of nitrogen enrich- ment on biomass allocation, growth, and leaf morphology of the seagrass Thalassia testudinum. Marine Ecology Progress Series 196:39-48. Lirman, D. and W.P Cropper. 2003. The influence of salinity on seagrass growth, survivorship, and distribution within Bis- cayne Bay, Elorida: field, experimental, and modeling studies. Estuaries 26:131-141. McMillan, C. and E.N. Moseley. 1967. Salinity tolerances of five marine spermatophytes of Redfish Bay, Texas. Ecology 48:503-506. Michelli, R, M.J. Bishop., C.H. Peterson, and J. Rivera. 2008. Al- teration of seagrass species composition and function over two decades. Ecological Monographs 78:225-244. Montague, C.L. and L.A. Ley. 1993. A possible effect of salinity fluctuation on abundance of benthic vegetation and associ- ated fauna in northeastern Elorida Bay. Estuaries 16:703-717. Pulich, W. Jr. 1998. Seagrass Conservation Plan for Texas. Texas Parks and Wildlife Department, Austin, TX, USA, 79 p. Pulich, W.M. Jr. and C.P. Onuf. 2007. Statewide Summary for Texas. In: L. Handley, D. Altsman, and R. DeMay, R., eds. Seagrass Status and Trends in the Northern Gulf of Mexico: 1940-2002. US. Geological Survey Scientific Investigations Report 2006-5287 and U.S. Environmental Protection Agen- cy 855-R-04-003, Washington, D.C., USA, p. 7-16. Quammen, M.L. and C.P. Onuf. 1993. Laguna Madre: seagrass changes continue decades after salinity reduction. Estuaries 16:302-310. Sokal, R.R. and E.J. Rohlf. 1995. Biometry, 3’^'* ed. W.H. Ereeman, New York, NY, USA, 887 p. Sumerson, H.C. and C.H. Peterson. 1984. Role of predation in organizing benthic communities of a temperate-zone seagrass bed. Marine Ecology Progress Series 15:63-77. Tolan, J.M., S.A. Holt, and C.P. Onuf. 1997. Distribution and community structure of ichthyoplankton in Laguna Madre seagrass meadows: potential impact of seagrass species change. Estuaries 20:450-464. Tunnell, J.W. and E.W. Judd. 2002. The Laguna Madre of Texas and Tamaulipas. Texas A&M University Press, College Sta- tion, TX, USA, 346 p. Virnstein, R.W. (1982). Growth rate of the seagrass Halodule wrightii photographically measured in situ. Aquatic Botany 12:209-218. Withers, K. 2002. Red and Brown Tides. In: E.W. Judd and J.W. Tunnell, eds. The Laguna Madre of Texas and Tamaulipas. Texas A&cM University Press, College Station, TX, USA, p. 255-258. Zieman, J.C. 1982. The Ecology of Seagrasses of South Elorida: A Community Profile. U.S. Pish and Wildlife Service, Office of Biological Sciences PWS/OBS'82/25. Washington, D.C., USA, 155 p. 75 Gulf and Caribbean Research Volume 22 Issue 1 2010 Obituaries - Rezneat Milton Darnell, Jr. (1924-2009) and Royal Dallas Sutkus (1920-2009) Molly Marie Darnell Henry L. Bart Jr. DOI: 10.18785/gcr.2201.10 Follow this and additional works at: http:/ / aquila.usm.edu/ gcr Recommended Citation Darnell, M. M. and H. L. Bart Jr. 2010. Obituaries - Rezneat Milton Darnelljr. (1924-2009) and Royal Dallas Sutkus (1920-2009). Gulf and Caribbean Research 22 (l); 77-78. Retrieved from http://aquila.usm.edu/gcr/vol22/issl/ 10 This Editorial is brought to you for free and open access by The Aquila Digital Community. It has been accepted for inclusion in Gulf and Caribbean Research by an authorized editor of The Aquila Digital Community. For more information, please contact Joshua.Cromwell^usm.edu. Gulf and Caribbean Research Vol 22, 77-78, 2010 REZNEAT MILTON DARNELL, Rezneat Milton Darnell, Jr., well- known and respected ecologist and marine biologist, died on 22 December, 2009 in Rez Darnell working on his book in his office of home, spring 2005. Minneapolis, MN after a brief illness witb pneumonia and suspected lung cancer. Rez was born in Memphis, TN on 14 October, 1924. His parents were Rezneat ROYAL DALLAS SUTTKUS Royal D. Suttkus, or “Sut”, as be was af- fectionately known to family and friends, bolds a special place in soutbeastern icb- tbyology, having described a significant component of the region’s ichthyofauna. On 5 January, 2010, the ichthyological and broader biological communities were awakened to the news that Royal D. Sutt- kus bad passed away one week earlier (28 December 2009) surrounded by family in Decatur, Georgia, less than six months shy of bis 90 birthday. Over a professional career spanning 65 years, be established a legacy that will serve the biological com- munities for many years to come. His great skill and bis insatiable appetite for field collecting are legendary. The collec- tions he amassed- primarily fishes, but also important regional collections of plants, aquatic invertebrates, amphibians and reptiles, and mammals -constitute one of the most comprehensive, long- term records of biotic change in existence. The following account of bis remarkable life is excerpted from an article currently OBITUARY JR. Milton Darnell, Sr. and Matilda Millen Darnell. Dr Darnell was Professor of Oceanography at Texas A&M University from 1968 until bis retirement in 1995 as Professor Emeritus. Darnell graduated from Southwestern College (now known as Rhodes College) in Memphis, TN witb a Bachelor’s degree in Zoology in 1946. He received bis Master’s degree in Biology &c Genetics from Rice University in Houston in 1948 and bis Ph.D. in Ecology from the University of Minnesota in 1953. Before coming to Texas A&M, Darnell served three years as Instructor at Tulane University in New Orleans, LA and 13 years as Assistant Professor at Marquette University in Milwaukee, WI. Dr. Darnell published numerous scien- tific papers on the ecology of the Gulf of Mexico. His last work. The American Sea: A Natural History of the Gulf of Mexico, soon to be published by the Texas A&cM Press, is a comprehensive book on the ecology of the Gulf of Mexico and is eagerly awaited by colleagues across the nation. His many graduate students have praised bis lec- tures and his ability to clearly and con- cisely explain the complex environmental problems of our planet. Dr. Linda Pequegnat, former Research Scientist in the Oceanography Department at Texas A&cM and a friend and colleague of Dr. Darnell’s says, “Rez has been called ‘The Great Synthesizer’ because of his ability to take detached scientific infor- mation and organize it into meaningful overviews that explain the ‘big picture’ of ecological relationships in the natural world. He was also a ‘Renaissance Man’ witb extensive knowledge and experiences in such diverse areas as music, languages, and history - in addition to bis vast scien- tific knowledge. His forthcoming book, soon to be published by the Texas A&cM Press, on the history, biology, ecology, and management of the Gulf of Mexico pulls together more information about the Gulf of Mexico than has ever before been amassed in one Volume.” Dr. Darnell was preceded in death by bis parents and by his older brother, Rowland Jones Darnell. He is survived by his loving and caregiver daughter, Molly Marie Darnell of Minneapolis, MN, his brother J. Millen Darnell of Memphis, TN, his first wife Jeanne Hellberg Darnell of Minneapolis, MN, and many nieces and nephews including James Darnell, serving his second tour of duty in Afghanistan. - Molly Marie Darnell Royal D. Suttkus from the foil of 2000 in the fish collection that would soon be named in his honor. in press in the journal Copeia. Suttkus was born 11 May 1920 in Ballville, Ohio, the third of four children of John Albright Suttkus and Myna Louise Schultz Suttkus. Roy- al, as he was called as a boy, developed a love for natural history in early childhood. He hunted rabbits and pheas- ant with brother Merlin, and enjoyed birding, gathering wildflowers and collecting in- sects. He taught his friends about horned worms and hawk moths. He fished with his father below the hydrodam on the Sandusky River, catching white and black crappie. He caught small fish with his hands while searching for crayfish among slabs of rock. He recalls seeing redhorse 77 suckers spawning along the Sandusky River and shooting an Egyptian goose with a bow and arrow along the Grand River in Michigan. He read Darwin’s On the Origin of Species while in high school. Suttkus graduated from Fremont Ross High School in 1937 then worked in a celery garden for 2 years at a salary of $0.25 cents per hour to earn money for college. In the fall of 1939, he enrolled in Michigan State University, eventu- ally majoring in Wildlife Management. Suttkus joined the R.O.T.C. at Michi- gan State, where he trained in field artil- lery. After earning his bachelor’s degree, he enrolled in Officer’s Commission School. When he finished his training, he was promoted to Second Lieutenant and attached to the 686th Field Artil- lery, an all African American battalion. His battalion went to South Wales in 1944 then crossed the English Channel to France, where his training was put to immediate use in the Battle of the Bulge. After his discharge from the Army in June 1946, he was accepted to the graduate program in the School of Agriculture at Cor- nell University, where he studied under Ed- ward Raney. He met his bride to be, Jeanne Elizabeth Robinson, while working for New York Fish and Game on Saranac Lake. They were married in December 1947. Son, Jay- son, the first of three children, was born in Ithaca, NY, two years later in January 1949. Suttkus accepted a faculty position in Zoology at Tulane University in the fall of 1950. Daughter, Ramona, was born in New Crleans in April 1951; daughter, Jan, was born in September 1954. Suttkus devoted his career at Tulane to collection building and studies of the taxonomy and natural history of specimens he collected. From 1963 to 1968, he was Principal Investigator of the NlH-funded, Environmental Biolo- gy Training Program, a summer program in which students received lectures and train- ing while in the field collecting and pre- paring specimens of plants, invertebrates, fishes, amphibians, reptiles, birds, mam- mals, and fossils. Additionally, he directed 24 graduate students during his career at Tulane University (10 M.S., 14 Ph.D.). In 1963, Suttkus started a consulting business with his long-time Tulane col- league, the late Gerald E. Gunning. Their first contract was a survey of ten stations on the Pearl River near Bogalusa, Loui- siana for a pulp and paper mill. The sur- vey started with monthly samples in April 1963, then switched to quarterly (seasonal) collections a year later. A quarterly survey of eight stations on the upper Pearl River was initiated in 1973. Suttkus continued both surveys until 2005. A survey of the lower Alabama River started in 1969 and continued until 2000. A survey of the Red River near Alexandria, LA was established in 1976 and ended in 2002. Shorter-term surveys were conducted on the Perdido Bay System, Sabine River, Mississippi River and Galcasieu River. All of the collecting on these surveys was supervised by Suttkus and involved standardized gear, technique and environmental sampling. Suttkus also collected marine organisms during oce- anic cruises in the Gulf of Mexico, Indian Ocean, off the coasts of Peru and Ven- ezuela, and around the Galapagos Islands. All of the specimens collected (fishes and any amphibians, reptiles, mussels, and decapods that happened to be collected) were preserved and ultimately cataloged into Tulane’s natural history collections. Suttkus published 125 papers during his career, including 54 of which deal directly with fish taxonomy and systematics, 41 on various aspects of fish life history and/or distribution, and 27 reports based on his fish monitoring surveys. As a sign of his tax- onomic breadth, 11 of his papers deal with mammals, three deal with crayfishes, and one deals with freshwater mussels. Among his systematic and taxonomic contributions are descriptions of 35 new fish species, 29 of which are freshwater species largely con- fined to the southeastern United States. Suttkus’s greatest contributions to southeastern biology were his collections. He built the Tulane fish collection on a foundation of just two mounted fish speci- mens left over from an early exhibit muse- um. By 1968, the fish collection had grown to a size of just over two million specimens, overfilling its space on the main Tulane campus. Later that year, the fish collection, along with birds, mammals and vertebrate fossil collections left over from the early exhibit museum, plus the thousands of specimens of plants, amphibians, reptiles, mammals and fossils amassed by Suttkus and students in the Environmental Biol- ogy Training Program, were moved to a 500 acre parcel of land on the Mississippi River near Belle Ghasse, LA, which Tulane had acquired from the U.S. Navy. The land, which had served as an ammunition stor- age depot during WWII, eventually became the F. Edward Hebert “Riverside” Research Laboratories. The collections became part of what was initially called the Systematics and Environmental Biology Laboratory. In 1976, Suttkus convinced the Tulane administration to formally recognize the collections at Riverside as the Tulane Uni- versity Museum of Natural History, and to appoint him as the Museum’s first Director. Suttkus officially retired from Tulane University in 1990. In fall 2000, a jubi- lee celebration was held in New Orleans to honor Suttkus’s 50 years of service to Tulane University and his contributions to southeastern biology. At a special clos- ing ceremony held under a tent beside the fish collection, the Dean of Arts and Sciences read a proclamation from the President, Faculty and Administrators of Tulane University, officially renaming the Tulane Fish Gollection, the Royal D. Sutt- kus Fish Gollection, and granting Suttkus the title of Emeritus Gurator of Fishes. Suttkus continued collecting and depos- iting specimens in the fish collection until just before Hurricane Katrina devastated the Gulf Goast in August 2005. Suttkus’s home near the beach in Ocean Springs, Mississippi was flooded and badly dam- aged by the high winds and storm surge that accompanied the hurricane. He lost nearly all of his possessions, including his field notes and most of his library. What little remains of his library is now part of the Royal D. Suttkus Fish Gollection. Since the hurricane, Suttkus and Jeanne had been living in an apartment in At- lanta, where he continued to publish his research. Suttkus had also been battling prostate cancer. His health took a down- ward turn in early December 2009. How- ever, family members say that his mind was clear and his spirits were high until shortly before he died. He is survived by his wife Jeanne, son Jayson, daughters Ramona and Jan and their families, brother Hazen and numerous extended family members. - Henry L. Bart, Jr. 78