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Tishomingo, OK, United States

Moore D.B.,Oklahoma State University | Moore D.B.,Murray State College | Ligon D.B.,Missouri State University | Fillmore B.M.,Tishomingo National Fish Hatchery | Fox S.E.,Oklahoma State University
Herpetological Conservation and Biology | Year: 2013

Exploited for food, traditional medicine, and pets, many turtle populations have been over-harvested or even extirpated from historic ranges. Most turtles possess life-history characteristics that complicate conservation efforts. These characteristics include delayed sexual maturity and high embryo and juvenile predation rates. Restoration strategies include nest protection, head-starting, and translocations. We examined short-term results of these strategies on a reintroduced population of Alligator Snapping Turtles (Macrochelys temminckii) in southern Oklahoma. We released 16 hatchery-raised juveniles and 249 adult M. temminckii into pools adjacent to the Washita River near Lake Texoma on the border of Texas and Oklahoma, USA. We tracked mortality and conducted nest searches to document factors related to population sustainability. We used hoop nets to recapture individuals and track growth. We confirmed seven mortalities during 2007 and none in 2008. In 2007 we located eight nests, all of which were depredated, and 18 nests in 2008, one of which was detected before depredation and successfully protected until hatching. We compared growth rates of released juveniles and members of the same cohort that were kept in captivity. There was no significant difference in dimensional growth, but released juveniles gained more weight than those retained at the hatchery. © 2013. Daniel B. Moore. All Rights Reserved. Source


Moore D.B.,Oklahoma State University | Ligon D.B.,Missouri State University | Fillmore B.M.,Tishomingo National Fish Hatchery | Fox S.F.,Oklahoma State University
Southwestern Naturalist | Year: 2014

We introduced 250 alligator snapping turtles (Macrochelys temminckii) originating from a turtle farm in Arkansas into six pools adjacent to the Washita River in Johnston, Bryan, and Marshall counties, Oklahoma. Additionally, we released 16 captive-bred and reared juvenile turtles. We used radiotelemetry and mark-recapture to monitor dispersal of turtles, selection of microhabitat, and patterns of movement. We placed transmitters on 16 adult turtles from Arkansas and 16 captive-bred juveniles 2-4 years old. We recorded 198 locations of 32 individuals by radiotelemetry between May 2007 and August 2008. We recaptured 45 turtles one-five times using hoop nets employed for 501 trap-nights. We compared movement and selection of habitat between sexes and age classes for the parameters water depth, bottom temperature, turbidity, and canopy cover. Adults and juveniles chose shallower depths with more canopy than available randomly. Additionally, adults chose greater depths than did juveniles, and juveniles chose areas with more canopy than did adults. There was no difference in selection of habitat between sexes. Adults utilized a larger linear home range than did juveniles. Source


Ligon D.B.,Missouri State University | Backues K.,Tulsa Zoo and Living Museum | Fillmore B.M.,Tishomingo National Fish Hatchery | Thompson D.M.,Missouri State University
Herpetological Conservation and Biology | Year: 2014

Juvenile turtles often lack sexually dimorphic morphological features, and as a result in many studies sex is often simply not determined. There are several alternatives for ascertaining sex, but they tend to be error-prone, expensive, time consuming, or require invasive surgery. We compared the age-specific efficacy of laparoscopic evaluation of gonads to cloacoscopic evaluation of genitalia to non-invasively determine sex of juvenile Alligator Snapping Turtles. These techniques were, in turn compared to sex determination by pre-cloaca tail length, an approach frequently used for assessing sex of many turtle species. Laparoscopy was reliable for identifying sex of juveniles as young as eight months and as small as 35 mm midline plastron length, cloacoscopy was reliable for animals that were at least eight years old and at least 165 mm midline plastron length. Tail morphology began to diverge between males and females at approximately 150 mm midline plastron length, but divergence was not complete except among sexually mature animals that were > 295 mm midline plastron length. Thus, laparoscopy likely remains the only reliable technique for sexing small juveniles, but cloacoscopy presents a viable non-invasive alternative for larger juvenile size classes. © 2013. Day Ligon. All Rights Reserved. Source

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