Category: Publications

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New paper on the imperiled Rattlesnake-master Borer Moth

Rattlesnake-master Borer Moths, Papaipema eryngii , are an imperiled species, that has had little genetic analysis done. A new paper from INHS PaCE Lab, led by affiliate Donald B. Shepard, examines the genetic diversity of this species across its range, information necessary to accurately inform management actions and Species Status Assessments.

Shepard and colleagues were able to collect legs of 72 specimens from the extensive collections of J. Wiker and J. Bess, representing 6 of the 8 states with historical records of the species. Mitochondrial haplotypes were shared in geographically separated populations indicating they were likely connected when their open grassland habitats were more expansive. Habitat corridors between existing populations can improve gene flow and prevent inbreeding.

Additional sampling and genetic analysis may be necessary to capture the more recent genetic shifts of populations separated by habitat fragmentation.

Read the full paper in Journal of Insect Conservation
Shepard, D. B., J.R. Wiker, J.A. Bess, T.L. Esker, J.A. Crawford, and M.J. Dreslik. 2025. Genetic Diversity and Historical Demography of the Imperiled Rattlesnake-Master Borer Moth (Papaipema eryngii). Journal of Insect Conservation 29 (4): 59. https://doi.org/10.1007/s10841-025-00698-0
 
Find more about our research on Papaipema
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New technique aids researchers in finding elusive mussel

A new paper in Ecology by Freshwater Mollusk Ecology and Conservation Program lead Sarah Douglass and colleagues describes the use of emerging technology paired with traditional methods to try to locate a species not seen alive in Illinois in over 100 years.

The Salamander mussel Simpsonaias ambiguahas been proposed for federal listing under the US Endangered Species Act.  Despite intense surveys, live individuals were last documented in Illinois in 1906.

The Salamander Mussel differs from other mussel species in that instead of a fish species, it uses the Mudpuppy Necturus maculosus as host for its glochidia.

The emergence of environmental DNA (eDNA) techniques provides a new method to guides surveys for potential populations.

Sarah Douglass and colleagues collected samples at 8 sites in the Sangamon River to test for both Mudpuppy and Salamander Mussel eDNA. Mudpuppy eDNA was detected in samples from 4 sites, 1 of which also contained Salamander Mussel eDNA. A group of surveyors returned to that site and conducted targeted searches of preferred habitat, yielding 12 live Salamander Mussels, the first seen in Illinois in over 100 years.

Read the complete paper here

Douglass, Sarah A., Savanna Palmer, Ashleigh R. McCallum, Olivia P. Reves, Hayley A. Robinson, Allison J. Rutledge, Jordan H. Hartman, Eric R. Larson, and Mark A. Davis. 2025. Environmental DNA Reveals the Salamander Mussel Simpsonaias Ambigua Alive in Illinois, USA , after a Century in Obscurity. Ecology 106 (7): e70145. https://doi.org/10.1002/ecy.70145.
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Note published on mammal predation on frogs

A ring-tailed vontsira (Galidia elegans) feeding on the frog Aglyptodactylus madagascariensis. Photo by Lonny Pace

Soon to be minted Dr. Edmonds had a paper published recently on an observation he made in Madagascar during his research to conserve endangered frogs.

Edmonds and co-author Lonny Pace documented a pair of ring-tailed vontsira engaging in predation and surplus killing of Aglyptodactylus frogs during an explosive breeding event at Montagne d’Ambre National Park.

Following a cyclone, Edmonds and Pace encountered a water filled depression with several hundred A. madagascariensis as well as two ring-tailed vontsira feeding on the frogs.

Read the full paper and see the video

Edmonds, Devin A. and Lonny Pace. 2025. Predation on a Breeding Aggregation of Madagascar Jumping Frogs (Aglyptodactylus madagascariensis) by Ring-Tailed Vontsira (Galidia elegans). Biotropica: doi.org/10.1111/btp.70059

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Raising frogs and advancing science

With over 40% of species at risk of extinction, amphibians are among the most imperiled groups on Earth. The biodiversity hotspot of Madagascar is not immune from this problem with nearly 47% of its endemic frog species at risk.

In 2010, Association Mitsinjo began working with IUCN and the government to develop an amphibian breeding facility. PhD Candidate Devin Edmonds has been working with the facility and their conservation programs. In addition to establishing captive assurance populations, this facility has provided important information on frog reproductive biology. The facility has successfully reared and released captive bred endangered Golden Mantella frogs into created habitat.

A paper, published today, reported on 1,272 captive breeding events from 11 additional frog species, including phenology, clutch sizes, oviposition, and larval development time. This information is often hard to obtain in the field, and these observations were the first described for many of these species.

Most of the species bred seasonally, but one, Mantella betsileanus, bred throughout the year and made up 86% of egg masses. Most species did not require environmental stimuli, aligning their behaviors with natural seasons, however Heterixalus betsileo only bred when placed in a modified rain chamber.

Researchers also learned that Gephyromantis mitsinjo lays eggs on land where tadpoles develop terrestrially within jelly, a behavior previously theorized but never observed.

The findings can help inform other captive breeding programs and increase success of conservation efforts for other imperiled species.

Read the complete paper in Zoobiology: Rakotoarisoa, Justin Claude, Andolalao Rakotoarison, Solonirina Rasoanantenaina, Eric Robsomanitrandrasana, Samina Sidonie Sam Edmonds, Jeanne Soamiarimampionona, Edupsie Tsimialomanana, Sebastian Wolf, Devin Edmonds. 2024. Captive breeding reveals insights into the ecology and reproductive biology of 11 little-known Malagasy frog species. Zoobiology: https://doi.org/10.1002/zoo.21876

 

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New paper on endangered Harlequin Mantella populations

Mantella cowani frog
photo by Devin Edmonds

The Harlequin Mantella is one of Madagascar’s most threatened frog species, known from 13 localities. The small, strikingly-colored frog that inhabits mountainous streams has been impacted by habitat degradation and illegal collection for the pet trade.

As part of a species conservation plan, PhD Candidate Devin Edmonds and his colleagues surveyed 11 of those sites and detected the frog at eight sites. The species is believed extirpated from the other three sites. Knowledge from local community members revealed two previously unknown locations, highlighting the importance of collaboration and engagement with the community.

Based on repeated surveys of three of the sites between 2015 and 2023, these small frogs can live 9 or more years in the wild as adults encountered in 2015 were still alive in 2023.

Despite finding two new sites, the populations are small and the frog is still imperiled. Conservation recommendations include upgrading the species to Critically Endangered. Continued monitoring of populations and habitats, and protection from poaching are necessary to conserve the species.

Read the paper published today in PeerJLife https://peerj.com/articles/17947

Edmonds, D., R.R. Andriantsimanarilafy, A. Crottini, M.J. Dreslik, J. Newton-Youens, A. Ramahefason, C. J. Randrianantoandro, and F. Andreone. 2024. Small population size and possible extirpation of the threatened Malagasy poison frog Mantella cowanii. PeerJ, DOI 10.7717/peerj.17947

 

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New paper on Timber Rattlesnake hibernacula

Timber Rattlesnake at hibernacula

PhD candidate Andrew Jesper has a new paper out today on determining suitable hibernacula for the state threatened Timber Rattlesnake. The initial habitat suitability model was developed based on known hibernacula across the state of Illinois. The model was refined over a series of surveys based on the model and updating the model based on information from the surveys. Habitat suitability models inform land conservation decisions, enabling prioritization of areas most likely to support suitable hibernacula.

ABSTRACT: The dependency on hibernacula for extended periods presents terrestrial reptiles with the challenge of locating thermally adequate hibernacula each winter. Defining the habitat characteristics of hibernacula is crucial for understanding the overwintering requirements and distributions of hibernacula-dependent reptiles, alongside identifying habitats which warrant special conservation concern. Our objectives were to identify the overwintering habitat characteristics of the imperiled timber rattlesnake Crotalus horridus in Illinois, USA, and to determine the distribution of likely hibernacula habitats throughout the state. Due to the initial sparsity of hibernacula records in Illinois, we adopted an iterative habitat suitability modeling process consisting of 3 distinct rounds of Maxent construction and revision. Each round was informed with updated information from model-guided surveys or by building rapport with in-state naturalists and researchers who knew of additional hibernacula locations. We created our final model using 36 hibernacula and identified slope angle (indicative of rock outcrops and shallow soils), topographical position index, forest patch area, and aspect (decomposed into 2 linearized variables: southness and eastness) as important drivers of C. horridus hibernacula habitat in Illinois. Together, the 5 variables and site surveys suggest the suitable overwintering habitat for C. horridus in Illinois is located on south- to southwest-facing outcrops on upper slopes and ridges of larger forest patches. Such habitat is distributed primarily in southern Illinois and throughout the Mississippi River and Illinois River border counties. Our study adds to the current understanding of the species’ overwintering requirements and provides a foundation for future ecological studies, management, and survey efforts throughout Illinois.

Read the full paper in: Jesper, A. C., S.A. Eckert, S.R. Ballard, J.A. Crawford, and M.J. Dreslik. 2024. Distribution and drivers of critical hibernacula for the timber rattlesnake Crotalus horridus in Illinois, USA. Endangered Species Research Volume 53, page 467

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Three new species of Mantellid frog from Madagascar

Three new species of frogs from Madagascar were described in a paper co-authored by PACE Lab PhD candidate Devin Edmonds, led by researchers at Zoological Institute at Technische Universitat Braunschweig.

The group of frogs, Genus Guibemantis, subgenus Pandanusicola, spend their lives in the Pandanus (screw-pine) trees, which are common in the Andasibe area of Madagascar. They live and reproduce in water that pools in the leaves of the trees. While surveying the trees, the researches observed frogs that did not look like any known species Genetic testing revealed 4 new species for the region, 3 of which were new to science.

frog
Guibemantis rianasoa – Beautiful Waterfall Frog – holotype male
Guibemantis vakoa holotype male
Guibemantis ambakoana paratype female

Read an article in the Miami Herald

Read the full paper at

Hugh Gabriel, Laila-Denise Rothe, Jörn Köhler, Sandratra Rakotomanga, Devin Edmonds, Pedro Galán, Frank Glaw, Richard M. Lehtinen, Andolalao Rakotoarison and Miguel Vences. 2024. Unexpected Diversity and Co-occurrence of phytotelmic Frogs (Guibemantis) around Andasibe, one of the most intensively surveyed Amphibian Hotspots of Madagascar, and Descriptions of Three New Species.  Zootaxa. 5397(4); 451-485. DOI: 10.11646/zootaxa.5397.4.1

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New publication on Timber Rattlesnake movement

PACeLab PhD Candidate Andrew Jesper co-authored a new paper with his undergrad research advisor Scott Eckert at Principia College. Jesper and Eckert radio-tracked 29 individual Crotalus horridus (13 female, 16 male) in Jersey County, Illinois.

On average, males move greater daily distances and occupy larger home ranges than females, particularly during the summer when Timber Rattlesnakes find mates. Females dispersed shorter distances from their hibernacula than males. Several snakes were tracked over multiple years, and returned to their same general range each summer. This site fidelity may limit the success of translocating adult individuals.

 

 

Abstract

Understanding the home range of imperiled reptiles is important to the design of conservation and recovery efforts. Despite numerous home range studies for the Threatened timber rattlesnake (Crotalus horridus), many have limited sample sizes or outdated analytical methods and only a single study has been undertaken in the central midwestern United States. We report on the home range size, site fidelity, and movements of C. horridus in west-central Illinois. Using VHF telemetry, we located 29 C. horridus (13 female, 16 male) over a 5-year period for a total of 51 annual records of the species’ locations and movements. We calculated annual home ranges for each snake per year using 99%, 95%, and 50% isopleths derived from Brownian Bridge utilization distributions (BBMM), and we also report 100% minimum convex polygons to be consistent with older studies. We examined the effects of sex, mass, SVL, and year on home range sizes and reported on movement metrics as well as home range fidelity using both Utilization Distribution Overlap Index (UDOI) and Bhattacharyya’s affinity (BA) statistics. The home range sizes for male and non-gravid C. horridus were 88.72 Ha (CI 63.41–110.03) and 28.06 Ha (CI 17.17–38.96) for 99% BBMM; 55.65 Ha (CI 39.36–71.93) and 17.98 (CI 10.69–25.28) for 95% BBMM; 7.36 Ha (CI 5.08–9.64) and 2.06 Ha (CI 1.26–2.87) for 50% BBMM; and 78.54Ha (CI 47.78–109.30) and 27.96 Ha (CI 7.41–48.51) for MCP. The estimated daily distance traveled was significantly greater for males (mean = 57.25 m/day, CI 49.06–65.43) than females (mean = 27.55 m/day, CI 18.99–36.12), particularly during the summer mating season. Similarly, maximum displacement distances (i.e., maximum straight-line distance) from hibernacula were significantly greater for males (mean = 2.03 km, CI 1.57–2.48) than females (mean = 1.29 km, CI 0.85–1.73], and on average, males were located further from their hibernacula throughout the entirety of their active season. We calculated fidelity to high-use areas using 11 snakes that were tracked over multiple years. The mean BBMM overlap using Bhattacharyya’s affinity (BA) for all snakes at the 99%, 95%, and 50% isopleths was 0.48 (CI 0.40–0.57), 0.40 (0.32–0.49), and 0.07 (0.05–0.10), respectively. The mean BBMM overlap for all snakes using the Utilization Distribution Overlap Index (UDOI) at the 99%, 95%, and 50% isopleths was 0.64 (CI 0.49–0.77), 0.32 (CI 0.21–0.47), and 0.02 (CI 0.01–0.05)), respectively. Our results are largely consistent with those of other studies in terms of the influence of sex on home range size and movements. The species also exhibits strong site fidelity with snakes generally using the same areas each summer, though there is far less overlap in specific (e.g., 50% UDOI) high-use areas, suggesting some plasticity in hunting areas. Particularly interesting was the tendency for snakes to disperse from specific hibernacula in the same general direction to the same general areas. We propose some possible reasons for this dispersal pattern.

Read the full article: Eckert, S.A., Jesper, A.C. Home range, site fidelity, and movements of timber rattlesnakes (Crotalus horridus) in west-central Illinois. Anim Biotelemetry 12, 1 (2024). https://doi.org/10.1186/s40317-023-00357-8

 

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New paper analyzing long term data on Ornate Box Turtle survival

box turtle
Ornate Box Turtle Photo by D. Edmonds

PaCE Lab doctoral candidate Devin Edmonds has a new paper in the journal Wildlife Biology: “Evaluating Population Persistence of Ornate Box Turtles (Terrapene ornata) at the Northeast Edge of their Distribution.”

This work analyzed 34 years of data from one site and 8 years of data from another to estimate female and juvenile survival and population growth over time. Being able to look at a population over a long period of time provides a better understanding of the population. This study also highlighted the need to protect adult female Ornate Box Turtles if the populations are to persist.

This work was co-authored with members of the Wildlife Epidemiology Lab.

 

Abstract: Turtles and tortoises are among the most threatened vertebrate groups. Their life history is characterized by delayed sexual maturity and a long lifespan, making populations susceptible to decline following perturbations. Despite the urgent conservation need, we are missing estimates of basic demographic traits for many species and populations. The ornate box turtle (Terrapene ornata) is a species lacking crucial demographic data. Many populations are isolated in fragmented habitats, especially in the eastern portion of their range. We carried out long-term capture-mark-recapture surveys on two isolated populations in northern Illinois to estimate population vital rates and project population persistence with deterministic stage-based matrix models. Using 34 years of data, we estimated adult female survival = 0.974 (95% CI: 0.946–0.988) and juvenile survival = 0.867 (95% CI: 0.688–0.951) at our most intensively surveyed site. At a second site using 8 years of data, we estimated adult female survival = 0.897 (95% CI: 0.783–0.954) and juvenile survival = 0.844 (95% CI: 0.551–0.960). Despite seemingly high annual survival rates, populations declined under population projections using mean vital rates. Population growth was most sensitive to adult survival, with increasing sensitivity under more pessimistic scenarios. Our results highlight the importance of long-term demographic studies for threatened species and demonstrate protecting adult female ornate box turtles is critical for ensuring populations persist at the northern edge of their distribution.

Read the full paper:

Edmonds, D.,  L. Adamovicz, M. Allender, A. Colton, R. Nyboer, and M. Dreslik. 2023. Evaluating population persistence of ornate box turtles (Terrapene ornata) at the Northeast edge of their distribution. Wildlife Biology 2023:e01183. doi: 10.1002/wlb3.01183

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New paper on more efficiently detecting Kirtland’s Snake

kirtland's snake
Kirtland’s Snake

Recent PaCE Lab graduate Tyler Stewart published a paper on his M.Sc. work creating a species distribution model for the rare and cryptic Kirtland’s Snake, Clonophis kirtlandii. He found that surveys Mid-May to early July when there was high cloud cover, moderate air temperature, and low relative humidity enhanced the detection probability of this species.

 

Abstract

Snakes are difficult to study due to their cryptic coloration, minimal movements, and use of inaccessible habitats. Although well‐timed surveys during a species’ active season can result in higher detection rates and conserve survey resources (i.e., time and money), survey effort may not ensure the detection of rare and cryptic species. Thus, in such instances, a strategic species‐ specific sampling design is needed. The Kirtland’s snake (Clonophis kirtlandii) is a rare, cryptic species assumed to be experiencing range‐wide declines. Naturalists have noted the disappearance of Kirtland’s snakes from various habitats since the early 1970s. The primary objective of our study was to determine detection of Kirtland’s snakes and the environmental and temporal factors influencing detection. We calculated the effort needed to detect individuals at sites by estimating detection probabilities of 3 known Kirtland’s snake populations in Illinois from 2019 to 2021. Based on 77 Kirtland’s snake detections over 226 site visits (34.1%) across 3 study sites, we found that high cloud cover, moderate air temperature, and low relative humidity enhanced the detection probability of this species. The middle of May to the beginning of July was the best time to conduct surveys when detection rates were highest. As our results suggested, it is imperative to establish strategic monitoring programs maximizing conservation resources to document populations for conservation action and range shifts for species of conservation concern, such as Kirtland’s snakes.

Stewart, T. A., A.R. Kuhns, C.A. Phillips, J.A. Crawford, and M.J. Dreslik.  2023. Estimating the effort required to detect Kirtland’s snakes (Clonophis kirtlandii). Wildlife Society Bulletin. http://doi.org/10.1002/wsb.1498