State of the Tortoise on the OISP

Views:

3 views

Gopher Tortoises Thrive
at the Orianne Indigo Snake Preserve

Dr. Christina Castellano, Director of Turtle Conservation for The Orianne Society, recently completed a comprehensive survey on the Orianne Indigo Snake Preserve (OISP) to estimate the population size and density of Gopher Tortoises (Gopherus polyphemus) on the tract. The OISP, the flagship preserve of The Orianne Society, provides a
safe haven for the threatened species. The Gopher Tortoise also plays an important role in the survival of the threatened Eastern Indigo Snake.

Dr. Castellano was joined by Orianne staff members Dr. Sean Doody, Kiley Briggs and Heidi Hall, who together with many dedicated volunteers walked
about 60 miles and examined nearly 800 Gopher Tortoise burrows with a specially designed camera that reaches deep into the burrow. The team was able to determine the number of residences occupied by
tortoises.

The results showed that the OSIP supports a thriving population of more than 500 resident tortoises that live at an average density of 1 tortoise per hectare (about 6 square miles).

The burrow of a Gopher Tortoise,
a keystone species in the southeastern longleaf pine ecosystem, is a long,
deep, subterranean tunnel which it digs with its front legs. This provides a
climate-controlled home for the tortoise and hundreds of other species,
including the Eastern Indigo Snake.

  Enlarge Photo

Dr. Castellano and
Dr. Doody scope Gopher
Tortoise burrows with a
specialized camera

Despite its solid frame and prolonged lifespan (more than 60
years), the Gopher Tortoise has declined because of habitat loss and
fragmentation, among other things. Translocation – movement of individuals from
one place to another – has become a common practice to establish new
populations of tortoises where they have disappeared and to increase numbers of
existing populations.

Last year, The Orianne Society had the opportunity to begin
a translocation project in collaboration with the Georgia Department of Natural
Resources (GDNR). Animals were moved from a nearby farm that was slated for
development to the OISP and Yuchi Wildlife Management Area (Burke County, GA). This
translocation has enabled the OISP to increase its tortoise numbers which, in
turn, will increase the number of tortoise burrows that the Eastern Indigos on
the property rely on for the shelter in the winter.

There are still many unanswered questions about the effects
of translocations on tortoises that are moved as well as those that are already
established in the area. Gopher Tortoises have interesting social systems that
scientists are just starting to explore. This spring, The Orianne Society and
GDNR are going to use radio-telemetry to investigate differences in habitat
use, movements and home ranges, and social interactions of both groups. It is expected
that the relocated tortoises will settle into their new homes and contribute to
Gopher Tortoise and Eastern Indigo Snake conservation for generations to come.