Meeting Abstract
Captive-reared animals may lack critical traits required for success in the wild. This can impede research or conservation efforts in which animals must be raised in captivity and subsequently released responsibly back into nature. We collected hatchling gopher tortoises from natural nests in southwest Georgia and raised them in the laboratory for physiology experiments that required having animals in controlled environments for prolonged periods. Upon completing the lab work, we outfitted 30, one-year-old individuals with radio transmitters and hard-released them in late summer at their nest sites to determine post-release behavior and survivorship. Most yearlings constructed burrows soon after release, and, like wild tortoises, released tortoises disproportionately placed burrows under deadwood. Video cameras located at tortoise burrows indicated normal activity patterns. Tortoises slept in burrows at night, emerged during warm daylight hours, basked extensively at burrow entrances, and limited time spent foraging away from the safety of burrow areas. Importantly, simulated predator approaches revealed that released tortoises showed normal antipredator responses by reliably hiding inside their burrows in response to potential threats. Released yearling tortoises exhibited survivorship similar to that of wild yearlings, 63-77% survived until the following spring. All known mortalities were due to predators. Despite having been raised inside plastic boxes and having daily contact with laboratory personnel for the first year of their life, captive-reared yearling tortoises retained critical traits necessary for success in the wild. These findings indicate that young gopher tortoises used in lab studies or captive-reared in efforts to augment wild populations may be successfully hard-released back into nature.
