Ohio Biological Survey Notes 6: 1-6, 2016. © Ohio Biological Survey, Inc.

A Review of the Current Status of Running Buffalo Clover (Trifolium stoloniferum ) in Ohio

Sean D. Leugers 1,4

'Advanced Inquiry Program, Miami University, Oxford, OH 45056; corresponding author: 7749 Kate Brown Dr., Dublin, OH 43017, (614)
542-7361, sean.leugers@gmail.com

Abstract: Running Buffalo Clover, Trifolium stoloniferum , is a federally protected plant with two populations in Ohio.
Although it had been generally accepted as extinct, populations were found in Ohio in 1985. Habitat losses, reduced
soil disturbance, and invasive species have been major causes of declines in Running Buffalo Clover (RBC). This
study investigated the status of RBC and provided additional evidence on several species impacting RBC’s survival.
Closely associated species are not well understood; however, endangered species of sage, bison, and elk are likely
the most important associated species for RBC’s survival, while white-tailed deer, rabbits, and cattle are detrimental.
Several findings in this report support an important association with bison or elk. Root nodules are lacking in RBC,
though they are present in closely related species of clover Bison and elk manure is high in nitrogen, and RBC has
loworgamc nitrogen-fixing abilities. There is an inverse relationship between available nitrogen and plants’ nitrogen
fixation capabilities. RBC requires a soil disturbance frequency that seems similar to bison migration frequencies.
Recovery effort plans are now nine years old and current information about the plant’s distribution and recovery is
lacking, RBC still experiences declines in remaining areas and is in need of more robust management plans. Future
investigations should focus on discovery of other suitable areas in Ohio for introduction, genetic analysis of RBC’s
ability to resist parasites, and the importance of bison and elk to RBC seed germination and survival.

Key Words: Running Buffalo Clover, Trifoflium stoloniferum , endangered plant, Ohio

Introduction

Running Buffalo Clover (RBC), Trifoflium stoloniferum , is an endangered plant found in a few fragmented locations in West
Virginia, Indiana, Kentucky, and southwestern Ohio (US Fish and Wildlife Service, 2007). RBC is a perennial legume that
produces runners with trifoliate leaves extending from one rooted crown system (Campbell et al., 1988). Its small white
flowers appear in April and last until about June, resembling the common white clover (USFWS, 2007) RBC’s natural habitat
includes forest edges, clearings, and trails where there is some sun exposure (Bartgis, 1985; Cusick, 1989). RBC also requires
elevated ground with layers of limestone underneath the soil (Andreas, Mack, and McCormac, 2004; Madarish and Schuler,
2002). Shortly after the arrival of European settlers in the Midwest, RBC began to decline due to habitat loss, elimination of
disturbances, loss of associated species, invasive species, and possible diseases (Aldrich, Bacone, and Homoya, 1986; Brooks,
1983; Madarish and Schuler, 2002; USFWS, 2007). RBC was considered to be extinct, but in the mid-1980s, small populations
were found in Ohio and in surrounding states (Bartgis, 1985). Unlike many legumes, RBC has low nitrogen-fixing capabilities
and therefore grows in slightly acidic soil and may require large herbivores for effective seed germination (Morris et al., 2002).
Disturbances produced by large herbivores, occasional mowing, logging, and fires are also important in sustaining the species
as well as preventing invasive species or more competitive plants (Homoya, Aldrich, and Jacquart, 1989; Madarish and Schuler,
2002). Although Campbell et al. (1988) and Cusick (1989) claimed that RBC was reliant on American bison ( Bison bison),
there is little evidence to support this claim.

RBC is listed as endangered at federal and state levels and much attention has been focused on recovery efforts (Madarish and
Schuler, 2002). RBC still requires continued management and monitoring (Scott et al., 2010) as evidenced by the Ohio Natural
Heritage Program’s (ONHP, 2007) finding that RBC populations have continued to decline in Ohio. With the USFWS (2007)
recovery plan now nine years old, there is a need for current information on the status of RBC’s population size, distribution,
and the effectiveness of recovery plans for Ohio and other states within RBCs historic range. The purpose of this paper is to
review the current status of RBC in Ohio and investigate important associated species.

Discussion

1

In Ohio, RBC was common in eight counties, but currently only two populations exist across three counties (ONHP 2007).
RBC has the ability to penetrate the tough, compacted soil that characterizes much of Ohio and can convert the soil to a higher-
quality soil (Madarish and Schuler, 2002). RBC also has the ability to withstand soil disturbances and droughts, making it an
important part of pastures, where it can provide a food source for production animals (Morris et al. 2002; Taylor et af, 1994).
RBC has a natural resistance to nematode infections that most cultivated clovers lack, making it agriculturally significant and
an interesting subject for pathogen study (Quesenberry et al., 1997). RBC is an integral part of its ecosystem (Singha, Baker,
and Bhatia, 1988) because of its important association with other plant species such as sedge, white snakeroot, and deer-tongue
(Madarish and Schuler, 2002).

Current Threats. Habitat destruction began in the 1700—1800s, when settlers cleared almost all of RBC’s native range for
agriculture and timber (Brooks, 1983; Campbell et al., 1988; USFWS, 2007). Cully, Cully, and Hiebert (2003) estimated that
only 1% of the original North American prairie remains. This area was RBC’s historic range and also supported vast herds of
bison and elk. Remaining habitat is highly fragmented and faces ongoing threats from continued development and the addition
of invasive species (Allen, 1994; Burkhart, Rentch, and Schuler, 2013; Morris et al. 2002). This loss of key habitat has been
cited as one of the main causes of decline in RBC and also played a role in the extirpation of other associated species (Campbell
et al., 1988; Cusick, 1989; Ford et al., 2003; Morris et al., 2002; USFWS, 2007). Disease has been cited as a contributor
to RBC’s declme (Bartgis, 1985), yet this seems speculative because no evidence of disease has been discovered in wild
populations (USFWS, 2007). Mildew has been found growing on RBC, though it had little effect on survival (Campbell et al.,

1988) . Still, disease should not be excluded from the list of threats given the low genetic diversity' of RBC populations (Hickey,
Vincent, and Guttman, 1991; Kongkiatngam et al., 1995).

Regular habitat disturbances are vital for reducing RBC’s competitors, such as trees and other secondary growth (Burkhart,
Rentch, and Schuler, 2013; Cully, Cully, and Hiebert, 2003; Madarish and Schuler, 2002). The frequency and intensity of
these habitat disturbances are important, though the measures have not been firmly established Timber forests, typically
cleared about once every 10 years, were found to have several populations of RBC growing along the logging trails (Madarish
and Schuler, 2002). Logging has been reduced in Ohio, leading to a decrease in disturbances and an increase in competitors
(Burkhart, Rentch, and Schuler, 2013; Pavlovic, 1994). Following the reduction in logging, the Ohio Department of Natural
Resources estimates that Ohio’s forest cover has improved from a low of 15% in 1940 to more than 30% by 1994 (ODNR,
1994). While the increase in forest cover may be hailed as an environmental success, it comcides with tire recent declines in
RBC populations. The loss of the disturbance events may also have left the soil less compacted, to the detriment of RBC, but
allowing other species to dominate the area (Burkhart, Rentch, and Schuler, 2013).

Closely Associated Species. The relationships and importance of closely associated species and RBC are not well understood,
though several are described. Madarish and Schuler (2002) found that sedge, white snakeroot, hog peanut, and deer-tongue
were often found with RBC. According to the ODNR (2013a), more than 55 species of sedge and 30 species of grasses are
in decline, which may contribute to RBC’s decline. Interestingly, Morris et al (2002) reported that deer-tongue, which is not
endangered, was always found among the areas with RBC. Herbivores play an integral role in RBC’s life cycle, but no actual
evidence has been provided to support any type of special relationship with any particular herbivore (Campbell, 1988; Cusick,

1989) . Establishing which species of herbivores are important associates has been difficult. Large herbivores, such as elk and
bison, were thought to be important, but by 1850, both species had been extirpated throughout RBC’s range (Cox, 2011; Ford
et al., 2003; ODNR, 2008). Research suggests that large herds of elk and bison grazmg on RBC across large migratory routes
likely provided ideal conditions with regular disturbances, effective seed dispersal, and manure that was high in nitrogen (Cox,
2011; Homoya, Aldrich, and Jacquart, 1989; Madarish and Schuler, 2002; Morris et al., 2002). Additional evidence comes from
a comparison of RBC to other closely related species. Unlike closely related clovers, RBC has poor nitrogen-fixing abilities and
lacks root nodules (Morris et al., 2002). In contrast, red clover {Trifolium pratense ) has root nodules and is efficient at nitrogen
fixation (Sturz et al., 1997). Large herbivores have shown a strong preference for RBC (Miller, Bratton, and Hadidian, 1992)
and their manure is high in nitrogen, vital to RBC’s survival (Morris et al., 2002). Ledgard and Steele (1992) reported that
plants’ nitrogen fixation ability decreases as the concentration of nitrogen in the soil increases. It is likely that RBC evolved
reduced nitrogen-fixing abilities as large herbivores’ manure provided an abundant source of nitrogen.

With the extirpation of large herbivores, populations of smaller herbivores such as white-tailed deer and rabbits increased
(Ford et al, 2003; Cox, 2011). Since 1970, the white-tailed deer population in Ohio has grown from 17,000 to 750,000
(ODNR, 2013b) and the population of Eastern cottontail rabbits is far larger now than before settlers arrived (ODNR,

2014). While elk and bison migrate across wide ranges, white-tailed deer, rabbits, and cattle remain in much smaller areas
(Cox, 2011; Ford et al., 2003; USFWS, 2007). In contrast, longer migrations of elk and bison may have provided wide
seed dispersal and the correct frequency of disturbances (Burkhart, Rentch, and Schuler, 2013; Ford et al, 2003; USFWS,

2

2007). Although white-tailed deer and rabbits have been proposed as replacements for large herbivores (Cusick, 1989), other
evidence refutes this. Campbell (1988) found that RBC declined when rabbits and white-tailed were allowed to graze in
the areas. RBC sites that were grazed by cattle also experienced declines, likely due to their intense and destructive grazing
habits (Burkhart, Rentch, and Schuler, 2013, Pavlovic, 1994). The highly intense grazing habits of cattle, white-tailed deer,
and rabbits may have selected for more competitive clovers or invasive species (Ford et al., 2003). Additionally, RBC seeds
consumed by white-tailed deer showed decreased rates of germination and survival, indicating a specific vector for seed
germination (Ford et al., 2003). RBC germination requires scarification of the outer seed coat (Campbell et al., 1988; Morris
et al., 2002). It is possible that only the dentition of large herbivores or the more extensive digestive systems of bison and
elk provides enough scarification along with adequate time in an acidic environment for RBC seed germination (Ford et al.,
2003).

Recovery Efforts. Recovery efforts for existing populations are focused around the Cincinnati area and Wayne National
Forest in southeast Ohio (USFWS, 2007). The former is protected and managed by the ODNR and Ohio Historical Society
and the latter is managed by ODNR (USFWS, 2007) After successful reintroductions of RBC in the 1980s, a drastic decline
occurred in 2005, possibly from an unknown disease and overgrazing (USFWS, 2007). In rare plant reintroduction efforts,
initial successes followed by sudden collapses are common and the causes are usually unknown (Allen, 1994). Although
disease cannot be completely ruled out, evidence to support the claim has not been found. The most plausible cause of recent
RBC declines is overgrazing by white-tailed deer and rabbits. White-tailed deer and Eastern cottontail rabbits were most
numerous in counties where RBC populations are found, and both were at record highs between 2003-2005 when the RBC
populations declined (ODNR, 2011; 2014). Miller, Bratton, and Hadidian (1992) found that white-tailed deer showed a
preference for RBC and quickly decimate populations. Given that the highest threat to survival seems to be from white-tailed
deer and rabbits, recoveiy efforts must eliminate these herbivores or restrict their access to RBC locations.

Selecting additional recovery sites may improve the overall effectiveness of conservation efforts for RBC. Elevation and
the presence of limestone formations are characteristic of the soil in areas around west and central Ohio (Ohio Division of
Geological Survey, 2006). There may be several areas that could be ideal RBC habitat and support reintroductions. Another
option is to reintroduce RBC to areas with existing herds of bison or elk. Cox (2011) referenced several isolated RBC individuals
at elk reintroduction sites in Kentucky. Reintroductions at these sites could increase the number of individuals and eventually
form another population.

Combining Efforts to Improve Conservation. While not all plants can produce roots from cut stems, RBC has shown the
ability to produce new roots in artificial media (Singha, Baker, and Bhatia, 1988). This makes RBC an ideal candidate for
research at the Cincinnati Zoo’s Carl H. Lindner Jr. Family Center for Conservation and Research of Endangered Wildlife
(CREW, n.d,). The facility is located in Cincinnati, Ohio, and specializes in rare species on the brink of extinction. Specimens at
this facility are preserved in artificial media and kept in long-term storage. A closely related native species, Trifoliuni calcaricum ,
has had similar declines, yet no specific causes were determined (Collins and Wieboldt, 1992). Similarities exist between RBC
and T. calcaricum , especially in terms of nitrogen fixation, and conservation efforts could be combined.

Understanding the nnportance of associated plant and animal species has been difficult because wild populations of RBC are
often rare and literature is lacking. While there is no information to indicate that research is being done on RBC at sites where
large herbivores have been reintroduced, it could be an opportunity to investigate and monitor them in their natural environment.
Studies of elk reintroduced to abandoned strip mines in Kentucky (Cox, 2011) could be combined with RBC investigations
because there is an important association between the two species. This area contams suitable habitat and isolated individuals
have been observed (Cox, 2011; USFWS, 2007). The Wilds is al0,000-acre park owned by the Columbus Zoo and Aquarium
(2012), located in Cumberland, Ohio. The park has a herd of bison (Columbus Zoo and Aquarium, 2012) and contains areas
that meet RBC’s habitat requirements (Ohio Division of Geological Survey, 2006). The park may be able to support recovery
efforts of RBC and provide an opportunity for additional research into the relationship of bison and RBC.

Future Investigation. All known populations of RBC exist in the southwest corner of Ohio and in the Wayne National Forest
(USFWS, 2007). Future investigation should focus on finding new populations and new areas for reintroduction. Allen (1994)
provided hopeful information about reintroduction through transplantation; however, there is no data to evaluate the long-term
effectiveness of this method. USFWS (2007) also discussed reintroduction, but specific methods and successful long-term
results were absent. Many of Ohio’s counties have significant elevation and are rich in limestone (Ohio Division of Geological
Survey, 2006), which may support unknown populations or could host reintroductions. Ohio has many abandoned coal mines
in counties near existmg populations of RBC (Harris, 2009) The existence of elk and bison in neighboring states creates an
opportunity to evaluate the shared successes and investigate further reintroductions. A shared conservation project between
these states could also provide an opportunity’ to investigate the importance of endangered species and closely associated

3

species. RBC is an ideal plant for researchers at the Cincinnati Zoo CREW facility, though no information could be obtained
to determine if this has already been done. Further investigation is needed to understand the genetics and mechanisms of
RBC’s natural pest resistance. If this property could be better understood, it could lead to a reduction in the use of agricultural
pesticides. The threat of disease must still be considered because remaining populations of RBC have low genetic variation and
may have no resistance to current or future diseases (Hickey, Vincent, and Guttman, 1991; Kongkiatngam et al., 1995). The
low genetic diversity of RBC identified by Kongkiatngam et al, (1995) will continue to be of concern and requires continued
monitoring of remaining populations.

Conclusions

Running Buffalo Clover is an endangered plant that exists in fragmented populations across its former range. It is an important
species for agriculture as well as a resource that can provide insight for agricultural pest management. Main threats include
habitat loss, reduction of disturbances, and invasive species (Madarish and Schuler, 2002). Within Ohio, two areas are home to
the remaining populations and are the focus of recovery efforts. Newer insight and compiled evidence supports that white-tailed
deer and rabbits are a larger threat than previously thought. Current declines in remaining RBC populations are likely caused
by the rapid growth of Ohio’s white-tailed deer and rabbit populations. Several findings in this report support an important
association with bison or elk Root nodules are lacking in RBC, though they are present in closely related species of clover.
Bison and elk manure is high in nitrogen and RBC has low organic nitrogen-fixing abilities. There is an diverse relationship
between available nitrogen and plants’ nitrogen fixation capabilities. RBC requires a specific soil disturbance frequency that
could be provided by migratory herbivores such as bison and elk; however, intense, destructive grazing by white-tailed deer,
rabbits, and cattle is detrimental. Sedge, deer-tongue, bison, and elk have important close associations with RBC and the effect
of closely associated species is more critical to the survival of RBC than previously thought. The loss of these closely associated
species has been the most significant factor in RBC’s decline. Cattle, white-tailed deer, and rabbits should be restricted from
all recovery sites. RBC’s low genetic diversity is a concern, though disease still does not seem to pose an immediate threat.
More work is needed in combining RBC conservation efforts with other endangered species. This would benefit multiple
species and foster understandmg of the nature and importance of closely associated species. Future investigations should seek
to evaluate the status of reintroduction efforts, the frequency and intensity of disturbances, and the genetics and mechanisms
of parasite resistance. After a thorough review of the literature, information on current distribution and status of recovery of
RBC is lacking,

Acknowledgements

I thank my classmates in the Advanced Inquiry Program for their suggestions and helpful comments. In particular, Dr. Kathayoon
Khalil and Julie Deiter provided much-needed editing and guidance during this project.

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Ohio Biological Survey Notes 6: 7-13, 2016. © Ohio Biological Survey, Inc.

Short-Term Effects of a Prescribed Burn on Butterfly Abundance and Diversity in a Restored

Northeastern Ohio Prairie

Patricia A. Bohls, Maci T. Nelson, Kailey N. Cooper, & Jennifer M. Clark*

Biology Department, Hiram College, P.O. Box 67, Hiram, OH 44234; * corresponding author: clarkjm@hiram.edu

Abstract: Prescribed bums are a common management technique used across the globe and are often used to control
encroaching vegetation in prairie systems. Although effective for managing vegetation, fire can have variable effects
on insects such as butterflies and is generally linked to disruption of reproductive cycles and host plant use. This
study was conducted to determine the effects of a prescribed burn on adult butterflies within a short time scale (3
months post-burn). Surveys were conducted in July 2013 (prior to the burn) and July 2014 (following the burn) using
a combination of plot and transect surveys. Overall, both total abundance and species richness declined significantly
following the prescribed burn. Responses, however, were species-specific, with three major outcomes: 1) some species
were detected in the summer prior to the burn but not following it; 2) some species were detected during the summer
following the bum but not prior to it; and 3) some species were found during both years. Pearl crescents {Phyciodes
tharos ), common butterflies in this area, significantly decreased in abundance following the burn. Further, great
spangled fritillaries, orange/clouded sulphurs, and cabbage whites, all common generalist species, were not detected
during surveys following the burn. These four common species were, however, detected in the control plot and during
transect surveys. Although not all butterflies were negatively affected, fire did adversely impact the community as a
whole. As insect pollinators continue to decline, prairie managers should consider using alternative methods such as
haying and grazing when possible. However, when fire is used, nearby refugia and host plants should be set aside and
conserved for sensitive species.

Keywords: Lepidoptera, fire, disturbance, pearl crescents, population, species richness

Introduction

Globally, insect pollinators have been in decline over the last several decades. Population losses have been linked to habitat
loss and fragmentation, use of agrochemicals, the spread of pathogens, introduction of alien species, and climate change
(see Potts et al., 2010 for a review). Because pollinators provide essential ecosystem services and play a key role in both the
ecological landscape and human society, conservation measures to protect insect pollinators have gained increasing awareness
through initiatives such as the Convention on Biological Diversity’s International Pollinator Initiative ( http://www.cbd.int/
decision/cop/?id=7 147 j. and through citizen science programs such as Bumble Bee Watch ( http://www.bumblebeewatch.Org/ j
and Monarch Watch ( http://www.monarchwatch, org/ j. Although most studies have focused on the decline of the European
honeybee {Apis mellifera ), many other pollinator species are in peril, including prairie-specialist butterflies, which have shown
rapid population declines over the last century (Orwig, 1992; Schlicht and Orwig, 1998).

It is estimated that approximately 98% of North American tallgrass prairie has been destroyed (primarily for agricultural use)
since European establishment in North America (Drache, 2001), and this has likely been a major cause in the decline of prairie-
specialist butterflies. As a result, prairie restoration projects have become common across the Midwest and are often managed
by controlled burns, mowing/haying, and/or grazing to maintain prairie vegetation, prevent forest succession, and control the
establishment of invasive species. Previous studies have shown that butterfly populations can benefit from prescribed burns
(Huntzinger, 2003; Panzer and Schwartz, 2000) or that prescribed burns have no net effect on species diversity (Fleishman,
2000). However, even if diversity is not influenced by burning, certain species may be affected differently and some management
practices may favor some butterfly species while negatively affecting others (Vogel et al., 2007). Conversely, there are several
studies that show declining trends of butterfly abundance and/or diversity following a prescribed burn (Swengel, 1996; Vogel
et al., 2010; Swengel et al., 2011) with recovery taking approximately three to six years or more (Swengel, 1996; Vogel et al.,
2010 ).

In this study, we surveyed butterfly populations within a restored prairie in northeastern Ohio prior to and approximately three
months after a prescribed burn. Surveys were conducted weekly during the month of July, when butterfly activity was at its
peak. Additional surveys were conducted in a nearby Monarch Waystation as a control, and transect surveys were completed

7

in surrounding habitats post-burn to compare species presence and absence. Although the literature suggests that the effect of
prescribed burns on abundance and diversity is not consistent across study sites, we predicted that burning would decrease both
plant diversity and butterfly abundance and diversity in the short term.

Methods

Field site description. All butterfly surveys were conducted at the James H. Barrow Field Station, Hiram College, Portage
County, Ohio (41.299521 N, -81.109085 W). This field station covers approximately 380 acres of land and is comprised of
beech-maple forest, wetlands, streams, and successional old field meadows. In 2008, approximately three acres (140,000 sq.
ft.) of continuously mowed grass were set aside for two major reasons: 1) to construct a zig-zag wetland to purify grey water
from field station buildings and 2) to allow for natural succession of meadow vegetation. In 2011, a native tallgrass prairie
mix including both grasses and forbs (packaged by Ohio Prairie Nursery) was planted in an effort to mimic the native prairies
historically found in northeastern Ohio. Following the planting in 2011, native seed has been scattered and additional plugs of
both grasses and forbs have been planted throughout the area. In April 2014, the first prescribed bum was completed over the
entire prairie for management purposes.

In 2009, a Monarch Waystation (approximately 200 m 2 in size) was constructed and certified according to Monarch Watch’s
Waystation standards. Although this garden was established to attract monarchs, several flowering species have been planted
to increase visitation of butterflies in general. This garden is situated approximately 70 m from the restored prairie. Due to the
close proximity and the lack of disturbance during the study, this garden was used as a control site for the restored prairie.

Butterfly surveys. A 200 m 2 plot was established in the restored prairie during the summer of 2013 (equal to the size of the
Monarch Waystation). Butterfly surveys were conducted weekly (N = 4 per site) throughout the month of July in both 2013
(pre-burn) and 2014 (post-burn) within both the restored prairie and the Monarch Waystation. Plots were surveyed between 10
a.m. and 4:00 p.m. on sunny days with winds no stronger than five on the Beaufort wind scale. Timed surveys were conducted
using four observers stationed within the plot for a duration of 20 minutes. To catalog both abundance and diversity, butterflies
were captured with butterfly nets and held in jars until the end of the survey period. Individuals not captured were identified
in flight and special care was taken to estimate numbers conservatively to avoid re-counting butterflies missed by netters. All
butterflies were identified to the species level and released live following surveys.

In addition to plot-style surveys, transect surveys were conducted during July 2014, on the same days as plot surveys, to allow
for a larger area of coverage and with the goals of surveying as many butterfly species as possible and detecting the presence
of species that may have not visited the restored prairie and/or Monarch Waystation. The transect was mapped out across the
James H. Barrow Field Station in accordance to standards set by the Ohio Lepidopterists Society for long-term monitoring
( http://www.ohiolepidopterists.org/bflvmonitoring/instructions/default.htm T This transect represented a variety of habitats,
including successional old fields, forests, and wetlands, and took approximately 45 minutes to walk at a moderate pace. All
butterflies within 15 feet of the recorder were identified and counted.

Flowering plant surveys. Plant surveys were conducted twice during July 2013 within the 200 m 2 plot used for butterfly
surveys in the restored prairie. In 2013, stem counts were completed for all plants that were in flower and plants were identified
to species. During July 2014, a visual inspection was completed during butterfly surveys in the restored prairie to catalog
species in flower and determine percent cover.

Statistical analyses. One-way ANOVAs were used to compare differences between July 2013 and 2014 for butterfly abundance
and species richness, pearl crescent abundance, and flowering plant species richness (JMP 10.0.0, SAS Institute Inc., 2012).
One flowering plant species was unable to be identified and was cataloged as an unknown.

Results

Butterfly surveys. Both total abundance (2013 average = 8.75 ± 2.32 [mean ± 1SE], 2014 average = 3.75 ± 0.25, ANOVA,
F (16) = 4.58, P = 0.0761) and species richness (2013 average = 2.75 ± 0.25 [mean± 1SE], 2014 average = 3.5 ± 0.28, ANOVA,
F (1 = 3.86, P = 0.0972) were not significantly different for the Monarch Waystation between July 2013 and 2014. Although
many of the species that visited the Monarch Waystation across these two summers were similar, there were some butterflies
that were detected in 2013 but not in 2014 (Table 1). Following the prescribed bum, both total abundance (ANOVA, F (1 =
72.98, P < 0.0001) and species richness (ANOVA, F (1 - 12.00, P = 0.0134) decreased significantly (Figs, la and b). In addition

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Figure 1. Average butterfly abundance (a) and species richness (b) (mean ± 1 SE) at the restored prairie from July
2013 (prior to the prescribed burn) and 2014 (following the prescribed burn) surveys.

to declines in overall abundance, pearl crescent ( Phyciodes tharos ) butterfly abundance (also an incredibly common butterfly
species) decreased significantly following the prescribed burn (2013 average = 14.75 ± 1.65 [mean ± 1SE], 2014 average =
2.75 ± 1.55, ANOVA, F (l = 28.10, P = 0.0018). Great spangled fritillaries (Speyeria cybele), orange/clouded sulphurs ( Colias
eurytheme I Colias philodice), and cabbage whites (Pieris rapae ) (three very common species at the James H. Barrow Field
Station) were detected prior to the prescribed burn, but were not detected following the burn (Table 2). These three species
were, however, detected in July 2014 in the nearby Monarch Waystation (Table 1) and during transect surveys (Table 3). Eastern
tailed-blue (Everes comyntas ) and mourning cloak (Nymphalis antiopa ) butterflies were detected prior to the prescribed burn,
but were absent from all surveys in July 2014. Although many common species were not detected following the prescribed
burn, four species absent during July 2013 surveys were found in 2014: silver-spotted skipper (Epargyreus clarus), cobweb
skipper (Hesperia metea), little sulphur (Eurema lisa), and little wood satyr (Megisto cymela). All but the cobweb skipper were
detected during transect surveys.

Table 1. Butterfly species detected at the Monarch Waystation during July 2013 and 2014 surveys. The “X” indicates

presence during that year.

Butterfly Species

July 2013

July 2014

Orange/clouded sulphur ( Colias eurytheme/C. philodice)

X

X

Pearl crescent ( Phyciodes tharos)

X

X

Great spangled fritillary (Speyeria cybele)

X

X

Summer azure (Celastrina neglecta)

X

X

Cabbage white (Pieris rapae)

X

X

Eastern tiger swallowtail (Papilio glaucus)

X

Horace’s duskywing (Erynnis horatius)

X

Banded hairstreak (Satyrium calamus)

X

Crossline skipper (Polites origenes)

X

Meadow fritillary (Boloria bellona)

X

Edward’s hairstreak (Satyrium edwardsii)

X

Common wood nymph (Cercyonispegala)

X

Little wood satyr (Megisto cymela)

X

Sachem (Atalopedes campestris)

X

European skipper (Thymelicus lineola)

X

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Table 2. Butterfly species detected at the restored prairie prior to the prescribed burn (July 2013) and following (July
2014). The “X” indicates presence during that year.

Butterfly Species

July 2013

July 2014

Orange/clouded sulphur ( Colias eurytheme/C. philodice )

X

Great spangled fritillary ( Speyeria cybele )

X

Cabbage white ( Pieris rapae )

X

Eastern tailed-blue (. Everes comyntas )

X

Mourning cloak ( Nymphalis antiopa )

X

Pearl crescent ( Phyciodes tharos )

X

X

Eastern tiger swallowtail ( Papilio glaucus )

X

X

Meadow fritillary ( Boloria bellona )

X

X

Common wood nymph (Cercyonis pegala)

X

X

Silver-spotted skipper (. Epargyreus clarus )

X

Little wood satyr ( Megisto cymela )

X

Cobweb skipper ( Hesperia metea )

X

Little sulphur ( Eurema lisa )

X

Flowering plant surveys. Visual inspection during butterfly surveys indicated that red clover (Trifoliumpretense , approximately
95% cover) and black-eyed Susans (Rudbeckia hirta) were the only two species present that were in flower during the month of
July. Flowering plant species richness was significantly higher during July 2013 (2013 average = 8.5 ± 0.5 [mean ± 1SE], 2014
average = 2.0 ± 0, ANOVA, F = 169.00, P = 0.0059) (see Table 4 for a complete listing of plants found during 2013 survey).

V *

Table 3. Butterfly species detected through transect surveys Table 4. Flowering plants surveyed during July 2013 (prior to
during July 2014. the prescribed burn).

Discussion

Surveys from this study showed that both butterfly abundance and diversity declined following the prescribed burn. Because
abundance and diversity did not differ between 2013 and 2014 in the nearby Monarch Waystation and common butterflies
missing from the restored prairie were detected during transect surveys, we can conclude that the effects of fire in the short

10

term were an important cause of declines in the restored prairie. These results are consistent with other studies in which overall
abundance declined on a short time scale following a bum (Panzer, 2002; Swengel and Swengel, 2007), However, this trend
is not consistent across geographical locations and systems. Some studies show that fire can increase butterfly abundance and
diversity (Taylor and Catling, 2012; Huntzinger, 2003; Verdasca et al., 2012; Scandurra et al., 2014), while sometimes it has
no net effect on diversity (Fleishman, 2000). Further, responses to fire can be species-specific, with some butterfly species
experiencing negative effects and others benefitting from this disturbance (Swengel, 1996; Mclver and Macke, 2014), Similarly,
surveys from tins study also showed that butterflies can have species-specific responses to fire. Because the prescribed burn had
marked effects on the flowering plant community, we suggest that this may be linked to overall declines and species-specific
responses.

Cool-season fires typically favor several dominant, native, warm-season grasses, which, in turn, reduce tire abundance and
diversity of forbs, especially when burns are frequent (Ewing and Engle, 1988). Further, plants that grow primarily in the cool
season are more likely to decline after a fire occurring in that same season (Ewing and Engle, 1988). In this study, flowering
plant diversity declined drastically post-burn; red clover was the main plant in flower, along with a small number of black-eyed
Susans Since many butterfly specialists feed pnmarily on forb species (Davis et al., 2008), this may explain the decrease in
abundance and diversity of butterflies following this cool-season prescribed bum.

In this study, four common species were found either in lower abundance following the burn (pearl crescent) or were completely
absent (great spangled ffitillary, orange/clouded sulphur, and cabbage white). These four species were found during surveys in
other nearby locations at the James H. Barrow Field Station during 2014, suggesting that they respond negatively to fire. Pearl
crescents, great spangled fritillaries, orange/clouded sulphurs, and cabbage whites are all considered to be habitat generalists
with regard to both habitat use and adult nectar sources. Great spangled fritillaries and cabbage whites are known to use red
clover as a nectar source and were expected visitors at this site. This reduction of generalist species is mconsistent with many
studies that show that specialist species are more negatively impacted by fire management than species that are more common
(see Swengel, 2011, for a review). Generalist butterfly species with broad habitat niches tend to recover more quickly following
a burn than specialist butterfly species, especially if source populations and host plants are nearby (Swengel, 1996). Vagility
and voltimsm can affect the recovery of butterfly populations, with multivoltine species colonizing more readily following fire
(Swengel 1996).

Conversely, our surveys showed that four species were found during post-burn surveys that were not detected during pre-burn
surveys: silver-spotted skipper, cobweb skipper, little sulphur, and little wood satyr. Adult cobweb skippers have been found in
association with burned landscapes and habitats with Andropogon spp., the larval host plant for this species (Shapiro, 1965).
Andropogon gerardi (big bluestem) is prevalent throughout the restored prairie in this study and recovered quickly following
the prescribed burn Cobweb skippers are considered to be fire-adapted because the first instars feed nocturnally underground
at the base of plants where they are protected from ground fires (Shapiro, 1974). Since silver-spotted skippers (Stichter, 2015)
and little sulphurs (Glassberg, 1999) are well adapted to disturbances, they may have been able to recover more quickly and/
or were visitors from nearby refugia. Further, the little wood satyr was found throughout the James H. Barrow Field Station in
2014, and nearby refugia likely contributed to its visitation to the prescribed burn plot.

Lastly, three species (the Eastern tiger swallowtail, meadow fritillary, and common wood nymph, all common species in
northeastern Ohio) were present during surveys for both years, suggesting that the burn did not have a substantial effect on these
species. Further, all three species were also found in high abundance during July transect surveys. Host plants for these species
are evenly distributed throughout the James H. Barrow Field Station property and this likely accounts for their visitation to the
prescribed burn plot.

Although this study showed species-specific responses, butterfly populations as a whole did not recover within a growing
season, which is likely linked to decreased plant diversity and direct mortality. Swengel (1996) suggests that for populations
that experience declines following a burn, recovery can take at least 3-5 years. However, it is common for newly established
prairies to be burned every year and then every 3-5 years once vegetation is well established. Although fire may benefit some
species, this prescription likely does not allow enough time for many butterfly species to recover In general, fire has negative
impacts on insect communities (see Swengel, 2001, for a review), but some taxa appear to recover quickly (within one to two
years), especially those with high vagility (Panzer, 2002).

There is growing concern among entomologists that prairie insect species may be threatened by prescribed burning practices.
Since this management tool can result in a substantial loss of insect species richness, several authors recommend that the
use of prescribed burns should be minimized (Orwig, 1992; Swengel, 1996). As pollinators continue to decline, managers
should consider using other methods such as haying, grazing, and brush-cutting to manage prairie plants. Areas formerly

11

burned may take six to eight years to become refuge habitat for butterflies (Swengel and Swengel, 2007), and using multiple
methods within a landscape would likely be less harmful to butterfly populations, as species respond differently to management
practices (Swengel, 1996). Further, areas should be set aside as a refuge when these management techniques are implemented.
In landscapes that are burned periodically, refugia offer persistent habitat diversity where organisms adverse to fire are more
likely to survive (York, 1999; Swengel and Swengel, 2007).

Acknowledgments

We would like to thank Zach Nemec, Sara Piccolomini, Michael Zielinski, Aaron Acus-Souders, Bryan Goldstein, Caitlin
Elkins, and Rachel Buckley for their assistance with field work. Special thanks to Emliss Ricks for his assistance with plant
identification and the Paul and Maxine Frohring Foundation for funding this project.

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