THE Tasmanian Naturalist Number 121 1999 Published by Tasmanian Field Naturalists Club Inc. ' * VOLUME 121 (1999) ISSN 0819-6826 T.F.N.C. Tasmaman Naturalist EDITOR: ROBERT J. TAYLOR CONTENTS Distribution, habitat and conservation status of the land snail Miselaoma weldii (Pulmonata: Punctidae). K.J. Bonham 2 A review of factors implicated in tree decline in Tasmania. M.G. Neyland 13 Will the introduced European green crab impact upon Patiriella vivipera , the rare endemic sea star? G.K. Prestedge 26 Will the introduced northern Pacific sea star impact upon Patiriella vivipera , the rare endemic sea star? G.K. Prestedge 29 Nest use by the common ringtail possum Pseudocheirus peregrinus in coastal tea-tree on Flinders Island. S.A. Munks 33 Distribution of the burgundy snail Helicarion rubicundus on the Forestier and Tasman Peninsulas. H. Otley, K. Bonham and R. Taylor 42 Deliniation of critical habitat for threatened species. M.J. Brown 48 Book Review 57 Published annually by The Tasmanian Field Naturalists Club Inc., G.P.O. Box 68 A, Hobart, Tasmania 7001 The Tasmanian Naturalist (1999) 121: 2-12. DISTRIBUTION, HABITAT AND CONSERVATION STATUS OF THE LAND SNAIL MISELAOMA WELDII (PULMONATA:PUNCTIDAE) Kevin J. Bonham 3/54 Duke Street, Sandy Bay, Tasmania 7005 Email: k_bonham@postoffice.utas.edu.au Abstract. The land snail Miselaoma weldii (Tenison-Woods, 1876) is currently listed as vulnerable under the Tasmanian Threatened Species Act. The species was surveyed on the Circular Head peninsula to investigate the status of populations on The Nut and to determine if it occurred elsewhere on the peninsula. On The Nut, it was found to occupy about four hectares of habitat in three discrete subpopulations. It occupied a wide range of native vegetation types and sometimes occurred in introduced vegetation. However, it had been eliminated by massive weed invasion and other past disturbances. M. weldii was not found away from The Nut. The population is estimated to be approximately 20 000. The Tasmanian population of this species warrants a classification of endangered. INTRODUCTION Miselaoma weldii is a small punctid land snail most readily distinguished by its reversed (sinistral) shell. It was discovered in the early 1870s by W.F. Petterd. Tenison-Woods (1876) described the species and gave the following quote from Petterd: “This small and reversed Helix I have only observed at the foot of the high rocks about Stanley, Circular Head, where I collected it with a few other species of Helices on the surface of blocks of rocks that are overgrown with a thick mass of entangled vegetation. It is extremely abundant and generally in clusters. I have collected some hundreds of specimens.” (p. 161) Petterd (1879) further commented that M. weldii was found in company with H. coesus (Pedicamista coesa) and H. stanleyensis (Pernagera officeri) and that “it appears to be strictly confined to the habitat given, where it is anything but rare.” The southern Victorian name Laoma sinistra (Gabriel 1930) is presently a synonym of M. weldii , but further work on this is desirable as the similar South Australian Miselaoma reevesbyi Cotton 1938 is definitely distinct from M. weldii. Recent records of M. weldii are few. Smith and Kershaw (1981) show the species as present in the 10km grid square below The Nut, but this record does not Status of M. weldii 3 seem to be matched to any museum specimen and may be a case of filling in all possible dots for a vague locality description. I recorded the species in good numbers in a small dogwood gully perched above the Stanley quarry in December 1988 and again in October 1991. Many sites near Circular Head (including around Smithton, Rocky Cape, Table Cape, the Hunter Islands and areas on the Black River) have been searched by various collectors without finding the species (Petterd 1879; author’s records; collections by Bill Mollison held in the Tasmanian Museum and Art Gallery). In the absence of any records away from The Nut, the species was listed as vulnerable under the Threatened Species Act 1995. In April 1998 a more detailed survey of the species was commissioned by the Threatened Species Unit to enable management recommendations to be formulated and to more accurately determine the status of the species. METHODS Previous species-specific surveys conducted by the author (eg for Tasmaphena lamproides and Anoglypta launcestonensis ) have used 15 metre radius (0.07 hectare) sites, which were searched for about 75 minutes. This was not considered appropriate for M. weldii , a tiny snail which requires much closer searching and which is known, where present, to occur in much greater densities. Instead, each site was an area of 0.01 hectares (typically a 10x10 metre square) which was searched for one hour. At some sites discrete small areas of searchable habitat occurring near each other were combined to make up the total 0.01 hectare area. Any available and accessible shelter was searched. Numbers of all snail species (native or introduced) seen during this time were counted, and subdivided into live and, in the case of Miselaoma weldii , dead specimens. Adults and juveniles were not differentiated as the proportion of clear juveniles in this species is very small; Microhabitats of live M. weldii seen were classified and recorded. Fieldwork was conducted between 12 and 17 May, 1998. On The Nut 17 sites were searched. Some additional informal searching was also undertaken near selected sites to verify the extent of populations and the species’ ability to occur under weeds. As most of The Nut is either cleared, massively weed-infested or dangerously steep, no attempt was made to proportionally sample the available habitat. Instead, sites were selected deliberately to obtain as much information about the species as possible. The largest areas of searchable habitat were found on the south and south-west slopes (eight sites), and the north and north-east slopes (eight sites). A site was also searched on top of The Nut, an area that has been almost entirely cleared. The peninsula away from the Nut was explored for the occurrence of habitat and suitable sites searched. Details of all sites, including site numbers, Australian Map Grid references, altitudes, descriptions of vegetation and tenure are given in Table 4 The Tasmanian Naturalist Table 1. Details of the sites where searching for Miselaoma weldii was undertaken on the Circular Head peninsula. Site Grid Reference Altitude Vegetation Tenure The Nut 1 35644859 60 Dogwood with gorse and ivy at cliff base State Res. 2 35654856 30 Introduced wattle, gorse and fireweed State Res. 3 35654857 60 Blackwood/dogwood scrub with creepers State Res. 4 35674856 80 B\ackwood/Melaleuca/Dicksonia scrub with nettles and weeds State Res. 5 35664856 90 DogwoodIBursaria/Banksia/Goodenia scrubState Res. 6 35674856 110 Dogwood scrub with gorse, Melalueca and tea-tree Quarry Res. 7 35644859 110 Banksia/Bursaria scrub with dogwood and Cyathodes State Res. 8 35714860 10 Foreshore shrubbery and rockfields State Res. 9 35704860 30 Dry tea-tree scrub with grass and Cyathodes State Res. 10 35694862 70 Eucalypt woodland with wattle, sedges and sclerophyll shrubs State Res. 11 35684862 110 Blackwood scrub with Bursaria and Correa State Res. 12 35674863 10 Boxthorn and succulents State Res. 13 35664858 130 Open sedgeland with Banksia State Res. 14 35674856 50 Blackwood/Dogwood scrub with Blechnum on rocks State Res. 15 35704860 40 Dry tea-tree scrub with Banksia and bracken State Res. 16 35704861 10 Foreshore shrubbery on rocks State Res. 17 35694863 10 Wattle and thick foreshore scrub State Res. Away from the nut A1 35544854 5 Coast wattle scrub with creepers Council? A2 35504849 10 Wet coast wattle scrub with tea-tree and various sedges Coast Res. A3 35464839 10 Blackwood/Melaleuca regrowth forest Coast Res. A4 35174804 5 Wet eucalypt/blackwood/A/0.05). However, females suckling back-young made significantly fewer changes in nest site than non-lactating females (t = 3.70, df = 14, P<0.01). Nest Use by Ringtail Possums 37 Table 1. Seasonal variation in the percentages of nests occupied by different combinations of males (M) and females (F) (back-young excluded) at Whitemark Beach. Month F M FM 2F Group composition 2M 2MF2FM 2F2M Total no. 3MF3FM of nests Jan. 44.4 40.7 - 11.1 - 3.7 - - - 27 Feb. 63.2 63.2 15.8 5.3 5.3 - 10.5 - - 19 Mar/Apr. 25.6 27.9 30.2 2.4 - 7.0 2.3 2.3 - 2.3 43 May 18.7 15.6 40.6 3.1 - 6.3 12.5 - 3.1 32 June 35.0 20.0 40.0 - - - 5.0 - - 20 Juiy 29.2 25.0 33.3 8.3 - - 4.2 - - 24 August 2.2 25.0 25.0 - - 5.6 5.6 - - 18 Sept. 6.1 35.5 38.7 - - 3.2 6.4 - - 31 Oct. 52.9 17.6 26.5 - - 2.9 - - - 34 Nov. 52.6 21.0 10.5 10.5 5.3 - - - - 19 Dec. 41.1 35.7 14.3 1.8 - 1.8 5.4 - - 56 All 36.0 30.0 23.0 3.4 0.6 2.8 4.6 0.3 0.3 0.3 323 80 70 60 Q> g 50 O 1— 3 40 O O 20 10 0 1 Ln In | Non-lactating adult females ] Females with pouch young FH Females with back young F,M 2F 2F,M 2M.F 3F.M Nest group composition 3M,F 2F.2M Fig. 2. Comparison of the occurrence of adult females of differing reproductive status in nest groups of different composition. 38 The Tasmanian Naturalist DISCUSSION Nest groups of the ringtail possum in this study appeared to be composed of members of a family group as noted in other studies of ringtail populations (Thompson and Owen 1964; Marsh 1967; How et al. 1984). Intolerance between males may be the reason that few instances of nest sharing by adult males were found. Although immature animals of a previous litter were occasionally found sharing a nest with an adult male and female pair, juvenile males were rarely found in a nest with their parents after they had reached sexual maturity. This suggests that adult males, as well as being intolerant of unrelated males, are intolerant of their male offspring. In contrast, daughters were often found sharing a nest with their parents after they had become sexually mature. Henry (1984) has proposed that elimination of breeding competition is the basis of the intolerance of juvenile males by adult male greater gliders Petauroides volans. Pahl (1985) also proposed that older dominant male P. peregrinus exclude young males from females. The long term fate of young male ringtails was not investigated in this study. However, a similar intolerance of male offspring in brushtail possum Trichosurus vulpecula (Dunnet 1964) and P.volans (Henry 1984) is followed by dispersal of juvenile males leading to a female-biased sex ratio. However, Pahl (1985) did not find a pattern of male-biased dispersal in P. peregrinus. In addition, the sex ratio of populations of P. peregrinus in Victoria (Thompson and Owen 1964; Hird 1975) and in this study did not appear to differ significantly from a 1: 1 ratio. How etal. (1984) did find the sex ratio to be biased toward females in a population at Sandy Point Victoria, but they attributed this to the higher survival of adult females compared with adult males (also noted by Pahl 1987). Further studies on the survival, dispersion and sociality of P. peregrinus are needed before the fate of young male ringtails excluded from the family group can be resolved. During the breeding season and when the females are suckling pouch young (April-September, Munks 1995) male and female pairs were common. Nests containing more than two adults or juveniles were also mainly encountered at this time. The larger nest groups could be a result of the social behaviour of ringtails at this time of year. However, there may also be a physiological advantage gained by the larger sleeping groups. Smith and Lee (1984) suggest that the formation of sleeping groups noted in the smaller species of arboreal marsupials may be related to heat conservation. Individual ringtail possums were found on their own most commonly during the spring and summer months, both in this study and by How et al. (1984). The larger nest groups during the winter months may therefore be a strategy to minimise energy costs associated with thermoregulation during the cooler winter days. Data presented here and by Thompson and Owen (1964) suggest that nest Nest Use by Ringtail Possums 39 sharing between mated adults of P. peregrinus tends to cease after the young have emerged from the pouch. This was similar to the situation observed in P. volans by Henry (1984) in which nest sharing only involved females who had failed to raise young. Smith and Lee (1984) propose that when females are solitary they do not need to share resources and hence may obtain more nutrients for reproduction. Alternatively, the tendency of female ringtails to remain alone whilst suckling back-young may have a more specific physiological basis. Ringtail possums appear to suffer heat stress during hot summer days (Pahl 1987; personal observation) and to facilitate evaporative heat loss they lick their paws, forearms and tail. Females suckling back- young would need to avoid heat stress at a time when their energy and water requirements are greatest (Munks and Green 1995). Therefore exclusion of males from the maternal nest may be a strategy to minimise the sleeping group size and hence reduce the chance of heat stress. Females tracked in this study appeared to remain in a particular nest site after their dependent young had emerged from the pouch. Similar observations were made by Morton (1977, cited in Read 1985) who found that female Sminthopsiscrassicaudata with older young were most likely to be caught at the same nest site. In some mammal species, particular nests are built for warmth and protection of the young from predators. These maternal nests appear to be larger and more dense than ordinary sleeping nests (Walser 1977). Several observations were made in this study of ringtail possums moving on the ground. Attempts to observe the animal’s behaviour on the ground were not successful since they were easily disturbed. However, most of these observations were made during mid to late spring and coincided with the appearance of new nests in the study area during October prior to emergence of the young from the pouch. Thompson and Owen (1964) also note increased nest¬ building activity at a time when most of the female ringtail possums carried pouch- young. Perhaps the construction of particular maternal nests is the reason behind this increased nest building activity. The results of this study support the observations made in other field studies that the ‘sleeping’ group structure of P. peregrinus falls into either the solitary, maternal, pairs or family class as defined by Smith and Lee (1984). Changes to the nest group composition throughout the year may have a physiological as well as a social basis. The fate of dispersing juvenile males and the role of sexually mature daughters found sharing a nest with their mother and siblings requires further investigation. ACKNOWLEDGEMENTS This work was undertaken as part of a Ph.D. program in the Zoology Department of the University of Tasmania. I thank Brian Green and Randy Rose for advice and constructive criticism during the development and writing of this work. The Department of Lands, Parks and Wildlife, in particular Nigel Brothers, Nick Mooney 40 The Tasmanian Naturalist and Peter Mooney, provided advice and permission to study ringtails. I am grateful to the Commonwealth Scholarship and Fellowship Plan and the Ingram Trust Fund for financial support. Thanks go to P. and G. Blunstone and H.C. Gavin for allowing the work to be carried out on their land. Thanks also go to all those who assisted in the field work, in particular the ‘no-aileron’ pilot Captain Rick who risked his life to get me, numerous volunteers and equipment to Flinders Island. Very special thanks go to the late Derek Smith for his hospitality, encouragement and lively discussions lubricated by many glasses of ‘Fruity Lexia’ throughout the duration of my time on Flinders Island. REFERENCES Dunnet, G.M. (1964) A field study of local populations of the brush-tailed possum, Trichosurus vulpecula, in eastern Australia. Proc. Zool. Soc. Lond. 142: 665- 695. Henry, S.R. (1984) Social organisation of the greater glider (Petauroides volans ) in Victoria. In Possums and Gliders, pp. 221-228. Eds. A.P. Smith and I.D. Hume. (Surrey Beatty and Sons Ltd., Sydney). Hird, D.G. (1975) Some aspects of the population ecology of the ringtail possum {Pseudocheirusperegrinus Boddaert 1785). M. Sc. Thesis, La Trobe University, Melbourne. How, R.A., Barnett, J.L., Bradley, A.J., Humphreys, W.J. and Martin, R.W. (1984) The population ecology of Pseudocheirus peregrinus'maLeptospermumlaevigatum thicket. In Possums arul Gliders, pp. 261-268. Eds A.P. Smith and I.D. Hume. (Surrey Beatty and Sons Ltd., Sydney). Klopfer, P.H. and Boskoff, K.J. (1979) Maternal behaviour in prosimians. In The Study of Prosimian Behaviour, pp. 123-156. Eds. G.A. Doyle and R.D. Martin. (Academic Press, New York). Marsh, M. (1967) Ring-tailed possums. Aust. Nat. Hist. 15: 294-297. Morton, S.R. (1977) Ecological and physiological studies of Sminthopsis crassicaudata (Marsupialia: Dasyuridae). Ph.D thesis, University of Melbourne, Melbourne. Munks, S.A. (1990) Ecological energetics and reproduction in the common ringtail possum, Pseudocheirus peregrinus (Marsupialia: Phalangeroidae). Ph.D. thesis, University of Tasmania, Hobart. Munks, S.A. (1995) The breeding biology of Pseudocheirus peregrinus viverrinus on Flinders Island, Bass Strait. Wildl. Res. 22: 521-534. Munks, S.A. Green, B., Newgrain, K. and Messer, M. (1991) Milk composition in the common ringtail possum Pseudocheirus peregrinus (Petauridae, Marsupialia). Aust. J. Zool. 39:403-416. Munks, S.A. and Green, B. (1995) Energy allocation for reproduction in a marsupial arboreal folivore, the common ringtail possum (Pseudocheirus peregrinus). Nest Use by Ringtail Possums 41 Oecologia 101: 94-104. Munks, S.A. and Green, B. (1997) Milk consumption and growth in a marsupial arboreal folivore, the common ringtail possum, Pseudocheirus peregrinus. Physiol. Zool. 70: 691-700. Pahl, L.I. (1985) The diet and population of the common ringtail possum (Pseudocheirus peregrinus) in southern Victoria. Ph.D. Thesis, Monash University, Clayton. Pahl, L.I. (1987) Survival, age determination and population age structure of the common ringtail possum, Pseudocheirus peregrinus, in a Eucalyptus woodland and a Leptospermum thicket in southern Victoria. Aust. J. Zool. 35: 625-639. Read, D.G. (1985) Development and growth of Planigale tenuirostris (Marsupialia: Dasyuridae) in the laboratory. Aust. Mammal. 8: 69-78. Smith, A.P. and Lee, A.K. (1984) The evolution of strategies for survival and reproduction in possums and gliders. In Possums and Gliders, pp. 17-33. Eds A.P. Smith and I.D. Hume. (Surrey Beatty and Sons Ltd., Sydney). Thomson, J.A. and Owen, W.H. (1964) A field study of the Australian ringtail possum, Pseudocheirus peregrinus (Marsupialia: Phalangeridae). Ecol. Monogr. 34: 27-52. Walser, E.S. (1977) Maternal behaviour in mammals. Symp. Zool. Soc. Loud. 41: 313-331. The Tasmanian Naturalist (1999) 121: 42-47. DISTRIBUTION OF THE BURGUNDY SNAIL HEL1CARION RUBICUNDUS ON THE FORESTIER AND TASMAN PENINSULAS Helen Otley', Kevin Bonham 2 and Robert Taylor 3 '44 St Georges Terrace, Battery Point, Tasmania 7004. Email: heleno@southcom.com.au 2 3/54 Duke Street, Sandy Bay, Tasmania 7005 forestry Tasmania, 79 Melville Street, Hobart, Tasmania 7000 Abstract. Helicarion rubicundus is an extremely localised species of snail that is restricted to wet sclerophyll and mixed forests on the Foresticr and Tasman Peninsulas. The results of all surveys for the species were col lated to better define the species ’ range and reservation status. H. rubicundus appeared to be more common in wet sclerophyll forests containing eucalypt species that shed copious bark in long sections, such as Eucalyptus viminalis, E. globulus and E. regnans. On the Forestier Peninsula no significant extension of its range beyond that previously documented was found. H. rubicundus was located in State Forest, Abel Tasman National Park and numerous smaller informal reserves and also occurs on private property. The southern section of Forestier appears to have a more continuous distribution, with a more patchy distribution north of (approximately) Hylands Road. On the Tasman Peninsula the species was located from over a five km north-south range between Arthurs Peak and Balts Road in State Forest and informal reserves. No snails were found further south along Fortescue Bay Road, west of Arthur Highway or east of Tatnells Hill Range. INTRODUCTION Surveys of the burgandy snail Helicarion rubicundus conducted in 1989 revealed a limited distribution in wet sclerophyll and mixed forests predominantly in State Forest on the Forestier Peninsula and a small area of the Tasman Peninsula (Taylor 1991). The species has been recommended by the Scientific Advisory Committee for inclusion on the schedule of the Threatened Species Protection Act 1995 with the status of rare. Comprehensive surveying and collation of published and unpublished records were conducted to better define its range and reservation status. METHODS Distribution of the Burgandy Snail 43 Searching was only conducted in wet sclerophyll forests with the presence of Banksia marginata and Exocarpus cupressiformis being used to delineate dry forests from wet forests. Dry forests were not searched as Taylor (1991) had shown H. rubicundus did not occur in this forest type. At each site surveyed, searching was conducted for 30 minutes or until an adult H. rubicundus (Fig. 1) was found, as juveniles of H. rubicundus and its congener, Helicarion cuvieri, were difficult to distinguish. Searching concentrated on curled bark, which appeared to be the preferred shelter site for the species (Taylor 1991). Other sheltering sites, including the underside of rocks and logs and within cutting grass ( Gahnia grandis) clumps, were also checked, particularly in sites with less curled bark. A number of habitat characteristics were recorded including dominant Eucalyptus species present and the number of H. cuvieri found. Grid co-ordinates were estimated from 1:25 000 maps. Surveys of 96 sites were undertaken by Helen Otley in April-June 1999 and 34 locations by K. Bonham between 1985 and 1998. In addition the 26 locations searched by Taylor (1991), three locations by B. Brown in 1996 and the type locality from Dartnell and Kershaw (1976) were also collated. The described surveying technique was used in all cases. HABITAT PREFERENCES H. rubicundus was recorded at 41 of the 96 sites sampled by Helen Otley. The Fig. 1 . The burgandy snail Helicarion rubicundus. Body length of the specimen shown is approximately 35 mm. Adults of this species are readily distinguished from its congener H. cuvieri by their burgandy body colour. 44 The Tasmanian Naturalist species appeared to be more common in wet sclerophyll forests containing eucalypt species that shed copious smooth bark in long sections, such as E. viminalis, E. globulus and E. regnans. Smooth bark was especially favourable as a shelter for juvenile specimens. In forests containing only E. obliqua, which has mostly fibrous bark, the snail was found on only six of 20 occasions and was more likely to be found in areas within its core range and/or areas with smooth bark species located nearby. The sites surveyed by Kevin Bonham also supported this finding. However this difference in rate of occurrence between these forest types was not significant (% 2 = 1.67, df=l). In general, Tasmanian snails are rarely affected by differences in eucalypt species present. Snails were generally not found in damp sclerophyll forests, such as northerly facing slopes, suggesting that H. rubicundus is possibly highly sensitive to soil and litter moisture. The lack of older plantations within the snail’s core range on either Forestier or Tasman Peninsula made it difficult to assess whether the burgundy snail recolonises plantation areas. H. rubicundus was located in a 20 year old plantation on the Tasman Peninsula. However this plantation may not be representative of plantations today as it was a different eucalypt species (Eucalyptus sieberi) and different establishment methods may have been used. A recent survey has shown that many Tasmanian snail species are common in 15-20 year old eucalypt plantations, but that Helicarion cuvieri is very much scarcer in plantations generally than native forests (Bonham 1999). H. rubicundus was found within some 15+year old silvicultural regrowth and areas with past selective logging (Taylor 1991; this study). H. rubicundus was also located at one unlogged site where there was evidence of a cool burn having occurred in the last five year. There was no apparent relationship between the density of H. rubicundus and H. cuvieri. H. cuvieri was found in 97 % of the sites surveyed by Helen Otley, suggesting it is more uniformly distributed than H. rubicundus. However it was observed that H. cuvieri generally showed a greater variation in body colour (black, chocolate brown and orangeish) at sites where H. rubicundus was absent and more black individuals were present at sites with H. rubicundus. This suggests that more intensive searching may need to occur at sites with a high density of darkly coloured H. cuvieri individuals. Elsewhere in Tasmania, H. cuvieri is often darker in colour in very wet forest sites similar to those where H. rubicundus occurs (K. Bonham, personal observations). DISTRIBUTION ON THE FORESTIER PENINSULA On the Forestier Peninsula, no significant extension of its range was found, with the burgundy snail found in 34 of the 61 sites searched by Helen Otley. The southern section of the Forestier Peninsula appeared to have a more continuous distribution, Distribution of the Burgandy Snail 45 Fig. 2. The location of successful and unsuccessful searches for the burgandy snail Helicarion rubicundus on the Forestier Peninsula. between Fazackerleys Range, Blackman Hill and Bellettes Creek/Browns Creek (Fig. 1). In the far northwest corner of its range H. rubicundus was only located at one of five sites searched by Helen Otley despite the abundance of smooth bark eucalypts. Information suggests the species is also present in low densities in the northeast section of its range. Thus the species was located at one site in this area by Taylor (1991) and by Kevin Bonham, but was not found in four separate 30 minute searches 46 The Tasmanian Naturalist Tasman Penisula Scale 1:100000 Other Tenure State Forest Formal Reserves Snail Absent (HO) Snail Present (HO) Snail Absent (other) Snail Present (other) Proposed Range Boundary Fig. 3. The location of successful and unsuccessful searches for the burgandy snail Helicarion rubicundus on the Tasman Peninsula. The proposed boundary of the range on this peninsula is shown by the dotted line. by Helen Otley. There were no other areas where the species appeared to be absent from wet sclerophyll forest on the Forestier Peninsula. Burgundy snails were also found in Abel Tasman National Park and numerous smaller informal reserves (Fig. 2 ). DISTRIBUTION ON THE TASMAN PENINSULA Distribution of the Burgandy Snail 47 H. rubicundus had a far more restricted distribution on the Tasman Peninsula; seven sites located over a five km N-S range between Arthurs Peak and Balts Road (Fig. 3). The snail was also less easily found within its range here compared to the Forestier Peninsula. No snails were found in forests south of the ridgeline along Balts Road, despite surveying at 18 sites. H. rubicundus was also not located in forests west of Arthurs Highway, despitesix surveys in wetEucalyptusdelegatensis forest. Theeastern limit of the species appears to be along Lichen Hill/Tatnells Hill Range. The reduced moisture content of soil and litter on the northern slopes of ranges may possibly limit the range of the species. Burgundy snails were located in three small informal reserves, including the Taranna Forest Walk, but Abel Tasman National Park is outside of the snail’s range on the Tasman Peninsula. STATUS The species has been classified as rare by the Tasmanian Scientific Advisory Committee for threatened species. Only a very small proportion of the range of H. rubicundus occurs on private property. The species does occur in informal reserves and within the Abel Tasman National Park. However, the majority of its range is State forest designated for production forestry. The preliminary results suggest that the species can inhabit silvicultural regrowth and that it also may occur in older plantations. Intensification of plantation development on State forest is planned within the range of the species. Hence, the potential impact of plantation development upon H. rubicundus requires further investigation. ACKNOWLEDGEMENTS We wish to acknowledge the use of unpublished data provided by Bill Brown. Penny Douglas, Luke Ellis, and Penny Wells prepared the figures. Roy Crookshanks and members of the Tasmanian Field Naturalists Club provided searching assistance during Kevin Bonham’s searches for the species. REFERENCES Bonham, K. (1999) Terrestrial Invertebrate Fauna in North-West Tasmanian Plantations Compared with Native Forest. Unpublished report. (Forestry Tasmania: Hobart). Dartnell, A.J. and Kershaw, R.C. (1976) Description of a new species of Helicarion (Stylommatophora: Helicarionidae) in Tasmania. Records of the Queen Victoria Museum 62: 1 -18. Taylor, R.J. (1991) Distribution and habitat of Helicarion rubicundus (Pulmonata: Helicarionidae), a rare land snail. Papers and Proceedings of the Royal Society of Tasmania 125: 27-28. The Tasmanian Naturalist (1999) 121: 48-56. DELINEATION OF CRITICAL HABITAT FOR THREATENED SPECIES M. Brown , S. Bryant , G. Edgar , G. Kantvilas f J. Kirkpatrick , P. McQuillan and A. Richardson Threatened Species Scientific Advisory Committee, C/- Threatened Species Unit, Department of Primary Industries, Water and Environment, 134 Macquarie Street, Hobart, Tasmania 7000 INTRODUCTION Under the Threatened Species Protection Act 1995 , critical habitat for any listed threatened species is the whole or any part of the habitat that is critical to the survival of that species. The Act states that the Scientific Advisory Committee (SAC), which was constituted under the Act, is to provide advice on the criteria to be used to determine critical habitats for threatened species. This paper discusses the approach that has been adopted by the SAC in developing a logical and scientifically justifiable process for the delineation of critical habitat. THE SUGGESTED APPROACH In Victoria and elsewhere, critical habitat for threatened species has been defined as those areas in which the species occurs, and those areas that are necessary to maintain appropriate conditions for a species within the areas in which it occurs. This approach is based on the general assumption that all populations of threatened species are likely to be important to their future, and has the practical virtue of avoiding legal arguments about exactly how many individuals need to be maintained. However, this form of definition of critical habitat ignores meta-population dynamics and does not allow for the potential for recovery. In order to account for such factors the SAC suggests the following approach for the delineation of critical habitat for threatened species in Tasmania. The critical habitat for a threatened species includes that part of the habitat of any listed species that is critical to the survival of that species. Usually in the case of endangered and vulnerable species, this would include all areas that are currently occupied by the species and which are at risk from threatening processes, unless: a) the threatening processes limiting a species’ population do not relate to the availability of habitat or its modification (eg. hunting, fishing, predation by feral animals, diseases). In such cases no critical habitat would be declared; b) part of the area occupied by the species is only inhabited intermittently, with individuals in this area not contributing to the perpetuation of the species. In this case only the areas necessary for the core populations would be declared critical habitat; c) an area does not support populations of the species at present but needs to be Critical Habitat For Threatened Species 49 protected in order to provide for future expanded populations, in which case it would be declared critical habitat. CASE STUDIES FROM TASMANIA In order to illustrate some of the issues associated with the delineation of critical habitat and how they would be dealt with by this proposal, a number of case studies of Tasmanian-listed species are presented below. Vascular Flora There are many species that exhibit different location patterns between years or decades, depending on climatic fluctuations or local successional processes. These species are generally moderately to highly vagile. The everlasting daisy, Leucochrysum albicans is one Tasmanian example. Populations have become extinct because of successional change that removes the bare ground necessary for their regeneration. Other populations have become established in places from which the species was previously absent but where appropriate regeneration conditions have been available. It is likely that the species has always been highly dynamic in its local occurrence. It is threatened probably because the distances between established populations and potential new sites have been increased by the widespread conversion of native grasslands and woodlands to the unsuitable habitats of improved pasture and crop lands. Any further loss of natural and semi-natural grassland and woodland in which it is not established at present for successional or stochastic reasons is likely to increase the probability of its extinction. Thus, in the case of this species, critical habitat for its long-term survival cannot be defined by its present distribution. In fact, its recovery might require translocation over land use barriers. Other species also occur as metapopulations, but their distributions are very circumscribed, and are readily defined on maps. Thus the local endemic Tetratheca gunnii is restricted to the ultra mafic rocks in the hinterland of Beaconsfield and critical habitat for the species can be defined by reference to the geological map for the area. Non-vascular Flora The state of knowledge of the distribution, biology and threat status of non- vascular flora is very scanty. For all groups, information on the critical habitat is likely to be more important than raw distributional data. However knowledge of critical habitat, entails problems of scale - it is difficult to define the minimal area of habitat, and its nature and stability are often unknown. Some species, especially fungi, are seasonal. Furthermore, many species are successional and it is unclear how criteria should be applied to colonisers. Distribution data can be indicative for species with many known locations. However, this is not the case for species that have only been recorded occasionally, and then only 50 The Tasmanian Naturalist incidentally through other studies. These problems are complicated by the lack of specialists and the consequent difficulty of identifying species in the field and of verifying data. Identification itself may require removal of the specimen, so adding to the depletion of the species. Some examples of lichen species not currently listed but having narrow habitat ranges are given below. Pyxine nubila (unlisted) This species is found in Tasmania, Saudi Arabia, Ethiopia and Kenya. It is unreserved in Tasmania and is found only in the Dysart area, on dry sandstone or mudstone overhangs on bluffs in very dry open eucalypt woodland or rough pasture. It is a very rare localised species and all known sites are subject to fire, grazing and possibly fertilising. Critical habitat could be defined and mapped by the occurrence of the appropriate geological formations in the area. Rocellinastrum flavescens (unlisted) This Tasmanian endemic species is found only in alpine areas, mainly on the western Central Plateau, where it is confined exclusively to the leafy twigs of conifers (Athrotaxis, Microstrobos, Diselma). Although all known sites are reserved, the species and its habitat are highly vulnerable to fire. Definition of critical habitat is difficult because the species is not ubiquitous on the conifers. In this case critical habitat probably would not be defined. Rather, management should be aimed at maintaining the distribution, health and vigour of the conifer populations. Heterodea muelleri (unlisted) This species is found in all Australian States, New Zealand and New Caledonia. In Tasmania it is found in lowland grassy dry sclerophyll and woodlands, mainly in the Midlands, where it grows on soil in open sunny clearings. It is reserved at Trevallyn and in the Freycinet National Park. This species is very common in mainland Australia, but is localised in Tasmania. The reserved populations do not adequately represent the species, as they are at the margins of its ecological range. Grazing and trampling are deleterious but occur over much of the species’ range. Many previously known populations have been eliminated by conversion to pasture. Its habitat is readily defined on maps, being some of the remnant native vegetation patches recognised as threatened by pasture establishment. These patches also contain many listed vascular plant species. Vertebrate Fauna Migratory and wide-ranging birds provide examples of threatened species that might have more extensive critical habitats than is indicated by their distribution at any given time. For example, the swift parrot requires adequate food (nectar) throughout its migratory range and suitable nesting habitat in Tasmania. The areas in which it feeds are likely to vary from year to year, depending on the patterning and intensity of flowering. Some of these areas could constitute critical habitat for the Critical Habitat For Threatened Species 51 long term survival of the species, if the populations are limited by food in a part of their range. Another example relates to the consequences of the mitigation of threatening activities within present ranges. For example, if the low population of orange-bellied parrots has been caused by inappropriate fire regimes in its breeding area, all of which is reserved, then the adoption of an appropriate patch-burning regime could lead to strong population growth. Its recovery might then be limited by the availability of its food plants in south-eastern Australia. At present potentially only arelatively small proportion of the salt marshes of Victoria might be sufficient to provide for its needs, whereas in the future a much greater proportion may be needed. Thus the concept of critical habitat based on present occurrence can potentially ignore habitat that might be necessary for the future recovery of a species. Other problems arise in the delineating of critical habitat where the survival of a species depends not only on the maintenance of the area in which it lives, but also on material flows from a much larger, and often variable, area. The Pedra Branca skink provides an excellent example of this, with its survival depending on a seasonal flow of food brought in by nesting seabirds, which in turn depend on the availability of food over a wide area of ocean. Some other specific examples of issues that arise are highlighted by the following species. New Holland Mouse (rare) This species is restricted to coastal areas in pockets from Asbestos Range National Park to Cape Portland. It is also in the Mt William National Park and has been recorded from Bicheno and Coles Bay. All known sites are below 200 m asl and within 15 km of the coast. The species requires a sandy substrate with a floristically diverse overstorey. On the basis of current knowledge, the species is largely confined to coastal reserve areas. The species requires regular burning to maintain suitable habitat conditions. Hence it could be threatened by loss of habitat if fire were to be excluded from heathland and open woodland within its range. Critical habitat could be defined and mapped as being all the existing locations of the species. However this species is probably best dealt with by appropriate management regimes rather than declaring critical habitat. Eastern-barred Bandicoot (nationally vulnerable) This species is distributed mainly in the north-west, south-east and localised pockets in the north-east, but is largely absent from the midlands. Population density fluctuates according to season and rainfall patterns. Traditionally its native habitat was open grassy woodlands but today the species is flexible, preferring any open grassy areas on deep fertile soils, with good rainfall and dense cover available. Threatening activities include fragmentation of habitat especially loss of cover 52 The Tasmanian Naturalist coupled with predation by domestic and feral animals. The species is locally extinct in its native habitat but does well in disturbed agricultural lands. Remnant grassy woodlands in the Midlands could be defined as potential future critical habitat, or ‘hot spots’ containing good populations in disturbed areas (eg Huon) could be identified as core critical habitat, or both. However, in this case critical habitat is probably not the most appropriate way of proceeding to secure the future of the species. Wedge-tailed Eagle (vulnerable) This species is distributed throughout Tasmania and offshore islands. Total population is estimated to be 300 - 400 individuals (100 breeding pairs). Some biological factors limiting its distribution and population include: spacing of the territory of adjacent pairs and the requirement for tall old growth eucalypts in sheltered situations for nesting. Threats include loss of nests and/or nesting habitat (either through fire or clearing), disturbance during the breeding season and persecution. It is not practicable to list all of the area the species occurs in. Thus the approach has been to protect known nest sites including a 10 ha buffer around the site. There are old growth patches containing suitable habitat throughout the State, but the density differs regionally. Determination of critical habitat would need to consider limiting factors in the various areas. The issue of identification of suitable habitat for future potential nest sites also needs to be considered. Grey Goshawk (rare) This species nests in wet and mixed eucalypt forest, rainforest, and swamp forest. Concentrations occur in the north and west with localised hot spots in the north-east and south-east. The population is estimated to be about 110 breeding pairs. Established pairs are sedentary with wide dispersal of juveniles. Threats involve loss of habitat and persecution. The main elements to target for critical habitat are known nest sites and foraging and nesting habitat in hot spot areas. There is the issue of establishment of new nest sites by new pairs as well as that of locating nest sites for pairs where nest sites are not known. For this species critical habitat would be centred around hot spots. Little Tern (endangered, nationally endangered) The species nests on beaches and islets associated with estuaries of exposed sand and low vegetation. It migrates during winter. It is distributed mainly in the north¬ east and east but information is scant. The population is estimated at fewer than 10 breeding pairs. The species suffers major disturbance while nesting on beach fore dunes. Some of this disturbance is natural, such as unusually high tides, but it is mainly from humans eg recreation. To determine critical habitat it is necessary to identify specific beaches used for Critical Habitat For Threatened Species 53 nesting over a long period, and to include a buffer around nest sites. Management would then mainly need to be on a seasonal basis to provide control of human disturbance. Some longer term habitat protection measure such as control of marram grass might also be required. Invertebrates Many invertebrates are highly sedentary, with restricted powers of dispersal. Thus their critical habitat is likely to be a subset of their geographical range. Other species exhibit marked fluctuations in their geographical extent over seasons, years or decades. These may have core areas that act as the sources for expansion in good years, while the peripheral populations tend to die out as conditions worsen. One life stage of a species might be widely distributed, but not lead to any long-term establishment outside its core areas. However, in the case of threatened aquatic species, survival will be dependent on conditions upstream and in the catchment, not only because of water quality issues but also because current-induced drift moves invertebrates downstream so that there has to be an upstream recolonisation by adults. Cave invertebrates, both aquatic and terrestrial, are highly dependent on conditions in the cave’s catchment. In these cases, assessment of critical habitat will have to include the catchment. A number of species at risk depend on decaying logs for at least some of their life cycle. For these species, an appreciation of the dynamics of log recruitment and decay is essential if their populations are to be maintained. Jewel Beetle Stigmodera insculpta (presumed extinct) This species is an endemic jewel beetle last recorded from near Miena in the 1920s. Jewel beetles are in decline in many parts of Australia, largely due to clearing of heathlands. In Western Australia, where several hundred species occur, land clearing and over-collecting have been identified as threats and all jewel beetles are protected by law irrespective of their population size or number. Larvae are stem borers, possibly in Leptospermum. In the case of the above species, survey is needed to confirm its status and to nominate critical habitat that cannot be identified at present. Moth Chrysolarentia decisaria (presumed extinct, recently rediscovered) This is a day-flying moth that occurs in open habitats. On the basis of unusually good historical records from 1888-1904, it appears this species was formerly widespread in the Tasmanian Midlands. All these sites have been revisited over the last ten years, along with many native vegetation remnants, without evidence of extant populations. In 1996 a precarious population was found at Township Lagoon Nature Reserve near Tunbridge where the larvae are associated with salt tolerant herbs. Loss of habitat and food plants are likely to be the key problems. At this site, hazards include vehicular movement, trampling and the potential for over collection. This species has also apparently disappeared from the western grassy plains of 54 The Tasmanian Naturalist Victoria since the 1920s. On present knowledge critical habitat is the lower catchments of saline lakes in the Midlands which retain some native herbaceous flora. Chaostola Skipper Butterfly (endangered) This is arguably the rarest butterfly in Tasmania. Only a single breeding population is currently known although others probably exist. It is not known what threatens the species but it has been very uncommon at least since the 1940s. The mainland subspecies is also in decline. Aspects of its biology make it vulnerable, especially its two year life cycle which subjects each generation to extended exposure to stochastic extinction events. Skipper butterflies typically suffer high parasitism and small populations are especially at risk. Although the larval food plant Gahnia radula is widespread in eastern Tasmania, only a tiny proportion of potential habitat appears to be used for breeding. Pimelea nivea is an important nectar source for the adults. Males are probably territorial like related species and hence population densities are likely to be low. There is currently minor illegal collecting pressure on this species. Critical habitat in this case will be wherever breeding populations can be found in nature. Such sites might sometimes be quite degraded. For example, a recent population at Conningham was breeding in low open forest subject to very frequent fires. Detailed survey is an essential first step. Moth Amelora acontistica (vulnerable) This is a conspicuously patterned geometrid moth known from two coastal sites in south-east Tasmania (Cremome and Lauderdale) and a site on Kangaroo Island in South Australia. Development of management prescriptions is inhibited by lack of knowledge of the life history. Based on knowledge of related species, larvae possibly feed on annual native herbs in saline coastal habitats. Critical habitat can only be defined once the life cycle is understood. For example, the critical habitat must contain the food plant. Ptunarra Brown Butterfly (vulnerable) This endemic butterfly is sedentary and largely restricted to elevated grassy plateaux or grassy woodlands. Comprehensive surveys in recent years have found approximately 150 populations, although many of these may be too small to be viable in the long term. Threats include loss of native grasslands due to plantation forestry on private land, inappropriate burning and grazing regimes and weed invasion. The fluctuations in numbers of some populations are being monitored. Critical habitat tor this species are core areas (>10 ha) which support large perennial populations. Sites less than 5 ha in extent are probably subject to extinction and recolonisation cycles since many small habitat patches are unoccupied. The clinal variation in the phenotype of this species is noteworthy and should be Critical Habitat For Threatened species 55 conserved as an example of genetic biodiversity. Therefore samples of habitat across the geographical range are needed. Mendum’s cave beetle (vulnerable) This troglodytic beetle has a restricted range within the large Exit Cave system where it is found on mud banks, flood litter and under stones at the edge of stream ways. Its critical habitat is thus smaller than the whole Exit Cave system, but it should include the catchment of the passages in which it is found. These may be quite local, both within the cave system and on the surface. Carabid beetle Catadromus lacordairei (rare) One of the largest beetles in Tasmania, this species is restricted to the northern Midlands. Being winged and fast running, it is capable of considerable dispersal but its actual distribution appears restricted to native grasslands on cracking soils. It is not known to survive in improved pasture. Both larvae and adults are predatory. Threats include conversion of native vegetation to pasture, and trampling by overstocking. A significant population occurs on the margin of Campbell Town and is potentially vulnerable to loss of habitat due to urban development in the future. All known populations are on private property. Critical habitat will be remnant native grasslands on clay-rich soils (typically basalt derived) in the northern Midlands which are lightly grazed by stock or native herbivores. Giant freshwater crayfish (vulnerable) The world’s largest freshwater invertebrate had a wide range across the north of the Tasmania, but with a clear disjunction at the Tamar graben. Its distribution has been fragmented by vegetation clearance, sedimentation and overfishing, and many populations have few large reproductive members. A moratorium on fishing for the species was declared in 1998. Gene flow between populations in neighbouring catchments is likely to be very low. Critical habitat for the species will be coincident with its current area of occupation, but should include areas upstream because of the necessity to maintain high water quality. Insufficient information is currently available to determine how far critical habitat should extend upstream of the occupied area. Blind velvet worm (endangered) The blind velvet worm is restricted to an area east of St Marys where it is found in approximately 200 km 2 of forest around Mt. Elephant and the Nicholas Range. It has a parapatric boundary with the giant velvet worm, Tasmanipetus barretti. T. anophthalmus is sedentary, and is found in Hitter and logs or in scree slopes. Despite its troglomorphic appearance, it has not been found in caves. The forested parts of the species range are critical, but within that area fallen logs and rock screes are particularly important. 56 The Tasmanian Naturalist Marine Flora and Fauna Many marine species can be treated in the same way as terrestrial species, but there are problems with some listed species which are effectively vagrants in Tasmanian waters. Spotted Handfish (nationally endangered) Three small populations are presently known in the Derwent estuary and Frederick Henry Bay. These areas (total area is about 5 km 2 ) can be defined on a map and comprise the critical habitat of the species. Other areas in the lower Derwent estuary where the species has been recorded in the past may be critical to the future survival of the species. However, presently it cannot be demonstrated that these areas are critical habitat that would be colonised if the population increases or colonies move. Cirrulicarpus polycoelioides (red alga) (potentially endangered) The present distribution of this endemic species is unknown. Collections have been made at only three sites ie Orford (pre 1876), Fluted Cape on Bruny Island at a depth of 23 m (1972) and Great Taylor Bay on Bruny Island at a depth of 2-5 m (1972). The latter two sites can be defined on a map and possibly could comprise the critical habitat of the species. The location from Orford was the site where the holotype was collected (described in 1876), and is so general as not to be useful. Some uncertainty is also associated with the latter two sites as the species is possibly widespread but ephemeral. Surveys of areas from Bruny Island would need to be undertaken before critical habitat was declared. Loggerhead turtle (endangered) No critical habitat can be defined for this species as the area it occupies is inhabited intermittently and is not essential to the survival of the species. CONCLUSION The above examples demonstrate that no single approach is able to cater for the multiplicity of distributional, biological and ecological situations and threatening processes that apply in Tasmania and thus that each species needs to be considered on a case by case basis. It is recommended that critical habitat normally only be defined when it is the most appropriate mechanism for ensuring the future survival of the species. 57 BOOK REVIEW John Gould in Australia: Letters and drawings By Ann Datta Published by Miegunyah Press, 1997. Reviewed by Don Hird John Gould was a man of many parts. Perhaps best known as the “Bird Man”, his worked spanned several continents when both travel and communication were difficult. His work extended to the Mammals of Australia and Kangaroos as well as many volumes on regional bird faunas and families of birds. Gould has been the subject of many biographical works and notes; this volume concentrates on correspondence relating to his Australian work. Gould’s background was modest although well-connected as his father was a gardener to members of the English aristocracy. Growing up in this environment, Gould may well have followed close to his father’s footsteps had not his interest and skill in taxidermy been noticed and rewarded. Reading this book one is struck by the fortuitous timing of Gould’s career. Taxidermy and presentation of exotic birds was becoming both an academic and popular endeavour in England early in his career. An age of empire and exploration was providing an abundance of curiosities, and museums and newly-established scientific institutions, together with private collectors, were buyers of collected specimens. Lavish presentation was the hallmark of Gould’s published work. Typically artwork would be reproduced as lithographs and hand coloured in folio-size volumes including Gould’s own text. This was no simple task. The business acumen required was considerable, with volumes usually being sold by installments from a prospectus. Their natural history value is inestimable. Some species, like the broad-faced- potoroo, were hardly seen after initial collection by Gould’s principal collector John Gilbert, and thus the typically meticulous notes in Mammals of Australia are about as much as we know of its biology. Much of the local interest in this large biographical work will stem from Gould’s extensive contact and correspondence with residents of Van Dieman’s Land. These included notables such as Governor and Lady Franklin, Ronald Gunn, Morton Allport, and the Rev. Thomas Ewing, who acted as subscription agent and with whom correspondence extended over several decades. Some correspondence is mundane, for example business matters such as bankrupt Van Dieman’s Land subscribers! Although there are many snippets of natural history interest I looked in vain for elaboration on, for example, Gould’s dismal but accurate prediction of the demise of the thylacine. This tends to amplify the impression of thoroughness in Gould’s original text. Wider contacts included Charles Darwin, Alfred Russell 58 The Tasmanian Naturalist Wallace and Professor Richard Owen. Illustrations are a feature of this volume and, as with the correspondence, many are reproduced here for the first time. Elizabeth Gould was the artist responsible for many of the earlier illustrations, and after she died in childbirth other artists were employed. This, together with the correspondence, indicate both the necessary perseverance and the inspiration evident in the Goulds’ work. ADVICE TO CONTRIBUTORS The Tasmanian Naturalist publishes articles on all aspects of natural history and the conservation, management and sustainable use of natural resources. These can be either in a formal or informal style. Articles need not be written in a traditional scientific format unless appropriate. A wide range of types of articles is accepted. Examples include observations of interesting or unusual animal behaviour, flora or fauna surveys, aspects of the biology and/or ecology of plants and animals, critical reviews of management plans and overviews on contemporary issues relating to natural history. Reviews of publications on Australian natural history are included. Unsolicited reviews are welcome as are suggestions for books to be considered for review. Submission of Manuscripts Manuscripts should be sent to Dr Robert Taylor, Cl- Forestry Tasmania, GPO Box 207B, Hobart, Tasmania 7000. Formal articles should follow the style of similar articles in recent issues. Informal articles need not fit any particular format. An abstract need only be included with longer articles. References cited in the text should be listed at the end of the paper in the following format: Ratkowsky, A.V. and Ratkowsky, D.A. (1976) The birds of the Mt. Wellington Range, Tasmania. Emu 77: 19-22. Watts, D. (1993) Tasmanian Mammals. A Field Guide. (Peregrine Press, Kettering). Ponder, W.F. (1993) Endemism in invertebrates in streams and rivers as demonstrated by hydrobiid snails. In Tasmanian Wilderness: World Heritage Values. Eds. S. Smith and M. Banks. (Royal Society of Tasmania, Hobart). Bryant, S.L. (1991) The Ground Parrot Pezoporous wallicus in Tasmania: Distribution, Density and Conservation Status. Scientific Report 1/91. Department of Parks, Wildlife and Heritage, Hobart. A good quality original of graphs, illustrations or maps should be provided. These can also be provided on computer disk in EPS or TIFF format. Formal articles are normally sent to an independent referee for comment. This is undertaken to try to ensure accuracy of information and to improve the quality of presentation. It should not be seen by prospective authors as a venue for their work to be critised but rather as a service to help them improve their manuscripts. The editor is willing to assist any prospective authors who have little experience in writing articles. After an article is accepted for publication, authors will be asked to provide a copy on computer disk, if possible. Tasmanian Field Naturalists Club G.P.O. Box 68A, Hobart, Tas. 7001 Founded 1904 OBJECTIVES The Tasmanian Field Naturalists Club aims to encourage the study of all aspects of natural history and to advocate the conservation of our natural heritage. The club is comprised of both amateur and professionals who share a common interest in the natural world. ACTIVITIES Members meet on the first Thursday of each month in the Biological Sciences Building at the University of Tasmania at Sandy Bay. These meetings include a guest speaker who provides an illustrated talk. This is followed by an excursion on the next weekend to a suitable site to allow field observations of the subject of that week’s talk. A mammal survey group also undertakes trapping and recording of native mammals in local areas. The Club’s committee coordinates input from members of the club into natural area management plans and other issues of interest to members. THE TASMANIAN NATURALIST The Club publishes the journal The Tasmanian Naturalist. This journal provides a forum for the presentation of observations on natural history and views on the management of natural values in both formal and informal styles. MEMBERSHIP Membership of the Tasmanian Field Naturalists Club is open to any person interested in natural history. The Tasmanian Naturalist is distributed free to all members, the club’s library is available for use and a quarterly bulletin is issued with information covering forthcoming activities. Enquiries regarding membership should be sent to The Secretary at the above address, by phoning Genevieve Gates on (03) 62278638 or by visiting our web site at www.tased.edu.au/tasonline/ tasfield/tasfield. htm. Membership Rates Adults $25 Families $30 Concession $20 Junior $20 m is'-? Subscription Rates for The Tasmanian Naturalist Individuals $ 15 Libraries $20 Overseas $25