REPTILES
Investigating Head-start Bog Turtle Movements and Habitat Use by Gabrielle Greater, Conservation Biologist/Herpetologist
T he bog turtle, Glyptemys muhlenbergii, is both federally (S/A) and state Threatened. The NC Wildlife Resources Commission (NCWRC) monitors this species to understand population status and trends. NCWRC staff have been releasing head-started turtles into a few select populations to augment declining populations. Our head-starting program is carried out in close collaboration with our conservation partners at Zoo Knoxville. First, we collect eggs from the wild and the Zoo incu- bates them in captivity. Once the eggs hatch, Zoo Knoxville staff rear the turtles and keep them in an artificial bog throughout their first winter. This “head start” allows the turtles to grow larger than they would if hatched in the wild, giving them a much-improved chance of surviving to adulthood. About one year after the eggs are collected, we return to the same bog and release the young turtles back into their home. Head-starting is one of many conservation tools we use to help this species, including habitat management and restoration, land protection, and collaboration with private landowners. This spring we began a new initiative to learn more about the behaviors and habitat uses of these head-started turtles via radio-telemetry. We lacked information on what head-started tur- tles did after release, including where they dispersed within the bog and what conditions they prefer. The illusive nature of bog turtles, coupled with the miniscule size of juvenile individuals means that most head-started turtles are not seen again until they are several years old. This makes it difficult to track the success of these turtles as they integrate into their new environment. With the use of radio-telemetry this summer, we have been able to observe head-started turtles consistently over six weeks, through- out various environmental conditions, to record information
about their movement patterns and habitat use. This work has also allowed us to affirm that they are moving into unsuitable habitat or leaving the bog. On June 5th, six 9-month-old individuals were released into three separate sections of a bog with a radio-transmitter attached to their carapaces. WRC staff tracked these individuals three times a week for six weeks. Along with their location, environ- mental conditions and microhabitat data were recorded. Several times throughout the monitoring period, the head-starts were weighed to determine if they were growing at the same rate as in captivity. This new information will provide useful information for the future. The tracking is ongoing, but thus far, we have learned that they are moving more than anticipated. Their short- term movements show much more activity than was expected for a yearling. In addition, the tracking period has been hot and dry, providing us with an opportunity to observe their response to this extreme change post captivity. We hope to repeat this work in future years to increase our sample size and learn more!
NCWRC Wildlife Diversity Technician using a receiver and antenna to track a bog turtle (2024).
24 2024 Wildlife Diversity Program Annual Report
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