Using three decades of data to save turtles

Champaign, IL – Protecting and restoring habitats are the most important steps that can be undertaken to protect turtle populations into the future according to a pair of recent papers analyzing 3 decades of data.

The Spotted Turtle, Clemmys guttata, is a small semi-aquatic turtle that inhabits sedge meadow, cattail marsh, wet-mesic prairie, and dolomite prairie in Illinois. It is protected as an endangered species in Illinois, which is at the western edge of its range. The two known populations in Illinois have been the focus of mark-recapture studies since 1988.

Recent analysis found that Spotted Turtle populations are limited by the amount of available habitat, suggesting that management efforts should focus on increasing suitable habitat. Control of cattails (Typha sp.) and restoration of sedges would increase the amount of available habitat.

Adults have a higher survival rate than younger turtles. Predators including raccoons and muskrats can eradicate eggs and juvenile turtles. While caging nests and headstarting juveniles will help the younger turtles, controlling predator populations could benefit all age classes.

Feng, C.Y.; Ross, J.P.; Mauger, D.; Dreslik, M.J. A Long-Term Demographic Analysis of Spotted Turtles (Clemmys guttata) in Illinois Using Matrix Models. Diversity. 2019, 11, 226. doi:10.3390/d11120226

Feng, C.Y.; Mauger, D.; Ross, J.P.; Dreslik, M.J. Size and Structure of Two Populations of Spotted Turtle (Clemmys guttata) at Its Western Range Limit. Herpetological Conservation and Biology 14(3):648–658

 

Spotted, Blanding’s, and Wood turtle ​ ​conservation symposium

PACE Lab head Michael Dreslik and herpetologist Jason Ross presented at the 2019 Spotted, Blanding’s, and Wood turtle conservation symposium held in West Virginia this November.

http://www.americanturtles.org/2019symposium.html

Population Viability Analysis and the Role of Head-starting for a northern Illinois Blanding’s Turtle Population

Rapid Demographic Assessments for Freshwater Turtles: Filling in Data Deficiencies

Radio telemetry used to improve environmental DNA use

Alligator Snapping Turtle

Environmental DNA (eDNA) is an emerging tool used to detect rare and difficult to detect species. A recent study by INHS PACE Lab herpetologists used radio telemetry to evaluate and improve the efficiency of this technique.

As part of a species reintroduction program, hatchling Alligator Snapping Turtles reared in captivity were tracked using radio telemetry to assess their survival. This work provided an ideal system for evaluating the efficacy and limitations of using eDNA to detect a bottom dwelling riverine turtle. At each radio location, water samples were collected as well as upstream and downstream of the turtle.

The researchers found that eDNA can be used to detect a benthic turtle species but that detection can be diminished by UV exposure from open canopy. This study shows the importance of continuing to use traditional methods such as radio telemetry to better understand the dynamics of eDNA in the environment.

 

Read the complete paper in Environmental DNA

White Cedar project presented at Great Lakes Coastal Wetlands Symposium

Sara Johnson, of the Molano-Flores lab at the Illinois Natural History Survey, presented a poster and lightning talk about Illinois Tollway funded research on the Effects of Soluble Salt on the Germination of Thuja occidentalis at the Great Lakes Coastal Wetlands Symposium in Maumee Bay, Ohio last week. This conference was the first symposium hosted by Audubon Great Lakes in partnership with the Great Lakes Coastal Assembly and Great Lakes Commission. Sara is a student representative for the North Central Chapter of the Society of Wetland Scientists and acts as Treasurer for the Student Chapter of the society at UIUC.

PaCE Lab at the Illinois State Fair

Smokey Bear using snake tongs

Members of the PaCE Lab exhibited in Conservation World at the 2019 Illinois State Fair, providing information and education to over 500 visitors. In addition to displays about the research being done by the group, visitors were able to try their hand at using actual field equipment used by scientists in their daily work.

The Illinois Bat Conservation Program had a mist net deployed where visitors could untangle, identify, and measure bats, all while wearing leather gloves.

The Amphibian and Reptile Conservation group had snake tongs, hooks, calipers, and radio telemetry equipment available for visitors to try to wrangle snakes into a snake bag, measure turtles, or track a hidden turtle.

Other activities included Build-a-Bug, where people can assemble the arthropod of their dreams (or nightmares) from a variety of general and specialized appendages, Wheel of Migration, about the risks migratory birds face, and locating PIT-tagged animals.

Smokey Bear using snake tongs
Gray Treefrog picked the right tent to visit
Wheel of Migration
Build a Bug
Vin Vasive wrangling a snake with a hook
Build-a-Bug

PaCE Lab at the Turtle Survival Alliance meeting in Tucson

Members and affiliates of the PaCE Lab presented 5 papers and 3 posters at the 2019 Turtle Survival Alliance conference held in Tuscson Arizona August 4th-8th.

Presentations

Baker, S. J., L Adamovicz, M. E. Merchant, and M. C. Allender. Site specific difference in health and immune function in Eastern Box Turtles (Terrapene carolina)

Dreslik, M. J., E. J. Kessler, J. P. Ross, K. A. Buhlmann, and P. P. van Dijk. Rapid demographic assessments for freshwater turtles: filling in data deficiencies.

Kessler, E. J., S. M. LaGrange, and M. J. Dreslik. Ontogeny of movement behavior in Alligator Snapping Turtles (Macrochelys temminckii): insights from a reintroduced population.

Merchant, M. E., L. Adamovicz, and S. J. Baker. Characterization of innate immunity of Eastern (Terrapene carolina) and Ornate (Terrapene ornata) Box Turtles.

Ross, J. P., D. Thompson, and M. J. Dreslik. Population viability analysis and the role of head-starting for a northern Illinois Blanding’s Turtle (Emydoidea blandingii) population.

 

Posters

Edmonds, D, and M. J. Dreslik. Clutch size in an Illinois Ornate Box Turtle (Terrapene ornata) population.

Kessler, E. J., S. M. LaGrange, and M. J. Dreslik. The influence of age and season on basking in Alligator Snapping Turtles (Macrochelys temminckii).

LaGrange, S. M., E. J. Kessler, and M. E. Merchant. Bite force scaling across size classes in the Alligator Snapping Turtle (Macrochelys temminckii) and Common Snapping Turtle (Chelydra serpentina).

PaCE Lab at Biology of the Pit-Vipers

PaCE Lab Members and affiliates presented four posters at the third Biology of the Pit-Vipers conference held in Rodeo New Mexico – July 11 – 14 2019.

Baker, S. J., E. J. Kessler, E. Haynes, A. N. Schnelle, and M. C. Allender. Disentangling the effects of season and temperature on hematological values in Prairie Rattlesnakes (Crotalus viridis).

 

Dreslik, M. J., J. A. Crawford, and S. J. Baker. Assessing abundance of a cryptic viper using N-Mixture models.

 

 

Jesper, A. C. B., and M. J. Dreslik. Timing and temperature cues of spring emergence for the Timber Rattlesnake (Crotalus horridus) in Illinois.

 

 

 

Merchant, M., and S. Baker. Innate immune activity in the Prairie Rattlesnake (Crotalus viridis).

New Publication on Spacial Ecology of Softshell Turtles

Read the complete article at https://www.mdpi.com/1424-2818/11/8/124:

Ross, J.P.; Bluett, R.D.; Dreslik, M.J. Movement and Home Range of the Smooth Softshell Turtle (Apalone mutica): Spatial Ecology of a River Specialist. Diversity 2019, 11, 124.

A new paper by INHS PACE Lab herpetologists examined the movement of the state listed Smooth Softshell Turtle, Apalone mutica, a riverine species. Spatial ecological information is necessary to guide the conservation efforts of river turtles. Turtles were radio tracked and found to move on average 142 m per day, but moved more when water was high or streams were larger. In most situations, females moved greater distances than males. This work will guide future studies of riverine species.

Long-term spatial ecology study of Timber Rattlesnakes

HerpetologicaContinuing his tradition of long-term studies on reptile populations, PACE Lab leader Dr. Michael Dreslik and colleagues recently published a paper in Herpetologica analyzing the spatial ecology of the Timber Rattlesnake (Crotalus horridus) in the Coastal Plain of Virginia. This study analyzed 17 years of radio telemetry data, with over 14,000 radio locations.

Crotalus horridus in the Coastal Plain are commonly called Canebrakes and occupy cane thickets, areas around swamps and river floodplains, forests, mountainous areas, and rural habitats. This differs from Illinois habitats which include heavily forested rock outcrops and bluffs.

This long-term study found that movement patterns observed in shorter term studies hold true:

      • males move greater distances than females,
      • males have larger home ranges than females, and
      • movement is greatest during the mating season.

Read the full paper in the current issue of Herpetologica.