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.

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

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.




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home range studies for the Threatened timber rattlesnake (Crotalus horridus), many have limited sample sizes or outdated analytical methods and only a single study has been undertaken in the central midwestern United States.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).


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:

UBAP lead and ornithologist Anastasia Rahlin presents on railway ecology

UBAP program lead and ornithologist Anastasia Rahlin was invited to present at the 2023 Railroad Environmental Conference (RREC). Her talk, titled “Railway Ecology: Using Railway Corridors to Restore Native Habitats and Preserve Biodiversity,” discussed the emerging field and made recommendations for future research.

There are 48,000 hectares of railway right of way in Illinois, 774,000 hectares in the US, and 4,122,000 hectares globally which could be managed for wildlife conservation.

Rahlin discussed where research efforts should be focused”

Collisions and wildlife crossings

    • Continue fencing high-speed railways
    • Create wildlife passages for low-vagility species

Habitat Restoration

    • Maintain native plant diversity in verges
    • Focus on restoring grasslands – appear more susceptible to invasive species

Species monitoring and management

    • Expand focus from large mammals
    • Standardized, repeated surveys needed to establish baselines
    • Need for robust occupancy and abundance models
    • Multi-year monitoring before and after construction/expansions
    • Investigate life history parameters for well-studied species
    • Adaptive management framework

Future Research

    • Before-After-Control-Impact (BACI) designs
    • Establish experimental vegetation plots along verges
    • Take advantage of novel technology

INHS PaCE Lab members present at The Wildlife Society meeting

Two members of the INHS PaCE Lab presented at The Wildlife Society annual conference November 5-9 in Louisville, KY.

scientific poster about point of care device to monitor birdsUBAP program leader and ornithologist Anastasia Rahlin presented a poster “Using Point of Care devices to assess Marsh and Sedge Wren food limitation”

Food limitation affects wildlife health and survival, may stem from differences in body condition or habitat quality between sites, and may be exacerbated by extreme weather events. Blood metabolites have previously been used as a food limitation index in birds. To assess changes in blood metabolites in marsh and sedge wrens, we used Point of Care devices to measure blood glucose, ketones, and triglyceride levels as short and long-term food limitation indices. We collected blood samples from wrens in May-August 2022 and 2023 in two Illinois DNR state parks and one dedicated conservation area in the Chicagoland Wilderness region over the duration of the breeding season. Our data indicate short-term food limitation may increase as the breeding season progresses for both Marsh and Sedge Wrens. Ongoing modeling will test whether body condition (age, fat and muscle scores), habitat quality (wetland extent and composition), or extreme weather (drought or flooding) best predicts glucose, ketone, and triglyceride levels over the course of the breeding season. Our findings will provide insights into physiological responses of sedge and marsh wrens to food limitations, and highlight the utility of using POC devices to rapidly measure blood metabolites in the field with minimal impacts to study species. An additional goal of this research is to use blood metabolite data to identify high-quality sites for migratory birds; our data will be used to evaluate the effectiveness of conservation areas at providing high-quality habitat. This work will inform wetland and wet meadow management strategies for migratory birds.

scientific poster about pond breeding amphibian egg massesARC program leader Ethan Kessler presented a poster “Reproductive output of forested ephemeral wetland-dependent amphibians across a modified landscape”


Forested ephemeral wetlands (FEW) support diverse communities of habitat specialist species across the eastern United States, including wetland-breeding amphibians (WBA). Due to their reliance upon FEW for breeding habitat, the location of FEW on the landscape influences population dynamics and distribution of WBA. Generally, FEW are difficult to detect due to their small size and position under the canopy, however, recent technological advances provide the ability to remotely detect FEW with great accuracy. Improved FEW detection methods enable a better understanding of how FEW characteristics and distribution influence WBA presence and abundance. We counted egg masses of two widespread WBA species, Spotted Salamanders and Wood Frogs, at 231 FEW on public lands in southern Illinois using a double observer methodology from 2020–2023. We then used local and landscape characteristics to predict egg mass abundance for each species. We found egg mass counts were highly correlated between observers for each species, but the presence and abundance of egg masses were not highly correlated between the two species. For Spotted Salamanders, we found a positive effect of wetland size on egg mass abundance but found no effect of canopy cover within a 200 m buffer. Conversely, for Wood Frogs we found no effect of wetland size, but egg mass abundance was positively associated with canopy cover within 200 m of FEW. Results from this study will provide a foundation for the estimation of WBA across broad geographic scales using discrete maps of FEW.


New Timber Rattlesnake publication by PhD candidate Andrew Jesper

Trailcam image of Timber Rattlesnake at den opening

Abstract: Many temperate reptiles survive winter by using subterranean refugia until external conditions become suitable for activity. Determining when to emerge from refugia relies on the ability to interpret when above-ground environmental conditions are survivable. If temperate reptiles rely on specific environmental cues such as temperature to initiate emergence, we should expect emergence phenologies to be predictable using local climatic data. However, specific predictors of emergence for many temperate reptiles, including the Timber Rattlesnake (Crotalus horridus), remain unclear, limiting our understanding of their overwintering phenology and restricting effective conservation and management. Our objectives were to identify environmental cues of spring emergence for C. horridus in Illinois to determine the species’ emergence phenology, and to examine the applicability of identified cues in predicting emergence phenology across the species’ range. We used wildlife cameras and weather station-derived environmental data to observe and predict the daily surface presence of C. horridus throughout the late winter and early spring at communal refugia in west-central and northern Illinois. The most parsimonious model for predicting surface presence included the additive effects of maximum daily temperature, accumulated degree days, and latitude. With a notable exception in the southeastern U.S., the model accurately predicted the average emergence day for eight other populations range wide, emphasizing the importance of temperature in influencing the phenological plasticity observed across the species’ range. The apparent broad applicability of the model to other populations suggests it can be a valuable tool in predicting spring emergence phenology. Our results provide a foundation for further ecological enquiries and improved management and conservation strategies.


Read the paper at:

Jesper AC, Eckert SA, Bielema BJ, Ballard SR, Dreslik MJ. 2023. Phenology and predictors of spring emergence for the Timber Rattlesnake (Crotalus horridus) PeerJ 11:e16044

Popular article: Discovering the Ornate Box Turtle: A Rare, Remarkable Illinois Reptile

Graduate student Devin Edmonds wrote an article for the August Issue of Outdoor Illinois, showcasing the subject of his M.Sc. thesis research, the Ornate Box Turtle.

Less common than their Eastern Box Turtle relatives, the Ornate Box Turtle is listed as state threatened. Learn more about this “Rare, Remarkable Illinois Reptile.”

Outdoor Illinois – Discovering the Ornate Box Turtle: A Rare, Remarkable Illinois Reptile

INHS PaCE Lab at the Joint Meeting of the Ichthyologists and Herpetologists

Dr. Dreslik and graduate students Blaine Hiner and Zander Perelman attended and presented at the 2023 Joint Meeting of Ichthyologists and Herpetologists in Norfolk VA, July 12-16.

The Continued Decline of the Eastern Massasauga in Illinois, from Distribution to Population Scales
Michael Dreslik, Tyler Stewart, Tom Beauvais, John Crawford

Marked changes have occurred to the earth’s biomes through the
Anthropocene due to human activity altering landscape-level processes. Many species reliant on ecosystems that have been heavily impacted have suffered massive range contractions and population declines. Given most prairies have been converted for agricultural purposes, species occupying those systems have exhibited precipitous declines. Here we examined the decline of Eastern Massasauga in Illinois using approaches at different scales, including g historical and contemporary distributions using Species Distribution Models and element-of-occurrence records to specific population trends using demographic monitoring. Unfortunately, the prognosis for the continued presence of the species on Illinois’ landscape is not promising.

Relating Habitat Parameters to Population Abundances in the Eastern  Massasauga
Michael Dreslik, Sarah Baker, John Crawford, Andrew Stites, Ethan Kessler

Before conservation measures can be taken, three questions about a species must be addressed: 1) where are they distributed; 2) what habitats do they use; and 3) how many do we have on the  landscape? Habitat suitability index
(HSI) models are primarily used to predict habitat quality on the landscape for a given species, but they also provide a method to answer the second question with the  supposition that the higher the suitability, the greater the abundance. The link between suitability and abundance estimations is often not made, even though both are critical for measuring conservation success. Here we  examined several habitat parameters to determine their efficacy at predicting population abundances of the Eastern Massasauga at their southern range limit in Illinois. Specifically, we tested whether parameters in an existing HSI model provided range-wide applicability or if proximate point- based or remote-sensed lidar-based measures of vegetation cover were better predictors.


Extrinsic Factors Influencing Hibernacula Occupancy of the Eastern Massasauga
Blaine Hiner, Michael Dreslik

Determining a species’ habitat use and distribution across a landscape
is essential for understanding the prevalence of declines due to larger-scale threats. At the landscape level, anthropogenic threats such as climate change and habitat destruction have triggered global population declines; thus, specific data crucial to combat declines must assess their impacts.
Collecting landscape-level data has been improved by the advent of occupancy modeling, which can elucidate the impacts anthropogenic factors have on population presence. The Eastern Massasauga is particularly vulnerable to extreme natural events from climate change and habitat loss in the western third of its range, particularly due to its reliance on specific overwintering habitats, which have been largely converted to agriculture. Extrinsic factors affecting overwintering habitat occupancy could include the burning regime, flooding events, aberrant seasonal climate, patch size, and juxtaposition of patches across the landscape. Using a long-term capture-mark-recapture dataset (1999 – present), we determined if extrinsic management and climate factors affected hibernacula occupancy rates. Our results would afford prioritization of site-specific habitat management actions to mitigate factors negatively impacting site occupancy.

Male-male Combat in Free-ranging Sistrurus Rattlesnakes
Zander Perelman, Terence Farrell

Although male-male combat is documented in numerous snake species, reports of combat behaviors are seldom more detailed than simple descriptions. Combat between snakes in the genus Sistrurus is rarely observed and only one previous account, focused on captive specimens, offered behavioral descriptions and analyses. Here, we discuss combat events between free-ranging Eastern Massasaugas (S. catenatus) in Pennsylvania, and free-ranging Pygmy Rattlesnakes (S. miliarius) in Florida. We used video recordings to describe and quantify observed combat behaviors. Additional behavioral contexts, specifically observed copulation (S. catenatus) and active defeat (S. miliarius), allowed for quantified behaviors to be analyzed and compared with knowledge of the winning male in both combat events. Quantifying and analyzing these two events has provided insight into important behavioral determinants of combat success in Sistrurus rattlesnakes. Observation of snake combat is opportunistic, and consequently, detailed behavioral descriptions and analyses as performed here are rare in natural settings. Such social behaviors have clear implications for reproductive success and fitness, and comprehensive analyses of combat behavior, as accomplished here, may prove useful in understanding the evolution of these reproductive behaviors.

The Illinois Natural History Survey Population and Community Ecology Lab is seeking a Terrestrial Ecologist to conduct basic and applied research assisting with ongoing surveys for bats. This position will assist with surveys of other taxa as time allows. This position will be based in Champaign, Illinois. See more or apply

Restored meadows can support plenty of prey for Eastern Massasauga

Current PaCE Lab graduate student Zander Perelman had two papers published recently from his M.Sc. research on Eastern Massasaugas in Pennsylvania.

The first paper reported on the prey community at a restored meadow in western Pennsylvania.

Often, restoration projects are focused on removing unwanted vegetation and re-establishing the plant community with the notion that “if you build it, they will come.”

In 2012, habitat restoration began at a well studied Eastern Massasauga site that had deteriorated through forest encroachment and natural succession. Restoration and follow up active management removed the canopy cover and returned it to a grassy meadow.

In 2021, to assess whether restoration efforts had created suitable habitat to supports prey species suitable for EMRs, Perelman and his colleagues conducted surveys of terrestrial vertebrates at the site using drift fences, cover objects, funnel traps, Sherman live traps, and active searches. Over 4 months they caught 9 species of amphibian, 10 species of reptile, and 11 species of mammal, for a total of 656 vertebrates. Their samples included 12 species documented as Eastern Massasauga prey items, many in high numbers.

Based upon their sampling they determined that the vertebrate community in the restored meadow habitat may provide the resident EMR population with a prey base that can support reproduction and sustainable population growth.

The second paper analyzed and formally described combat rituals between two male Eastern Massasaugas in the presence of a radio-implanted female. While tracking a gravid female, a male was observed nearby. Two days later, a second male was observed near the pair and Perelman was able to record 17 minutes of male-male combat.

This video provided the first formal analysis of these behaviors of male Eastern Massasaugas in the wild. The snakes spent much of their time in a raised and engaged position (RE), but also were intertwined for over a minute, attempted to top each other, and tongue flicked. The snake who ultimately copulated with the female appeared to be more persistent and engaged in the combat and perhaps most importantly, was more successful in topping his opponent..

Read the full papers:

Perelman, Zander E. ,  William I. Lutterschmidt, and Howard K. Reinert. 2022. Community Structure of Terrestrial Vertebrates in a Restored Meadow Habitat in Pennsylvania: Assessing the Potential Prey Base for Eastern Massasauga Rattlesnakes. Northeastern Naturalist,Volume 29, Issue 3 (2022): 370–381

Perelman, Zander E. ,  William I. Lutterschmidt, and Howard K. Reinert. 2022. A behavioral analysis of male-male combat in the Eastern Massasauga (Sistrurus catenatus). Herpetological Review: 53(3): 381-384

Contact Zander Perelman for more information

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