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SCCF ‘Scoping Out’ Gopher Tortoise Burrows
SCCF’s Wildlife & Habitat Management team has begun their annual gopher tortoise burrow surveys with a new method this year — video scoping.
“Using an endoscope camera attached to a PVC pole, the insides of a gopher tortoise burrow can be visualized,” said SCCF Wildlife Biologist Mike Mills. “Usual signs of activity include tortoise tracks going in and out of the burrow, the ‘mouth’ of the burrow having a well-defined, half-moon shape, and a tidy burrow entrance with little to no natural debris.”
However, basing the burrow activity status on these characteristics alone may not always be totally accurate.
“That’s where burrow scoping comes in. The camera gives us a better picture of what is going on inside the burrow. This technique allows for higher accuracy in determining if a burrow is being actively used or not,” said Mills.
It also can provide information on what other animals are utilizing the burrows, such as frogs and insects. With recent hurricanes and storm surge events affecting Sanibel’s gopher tortoise population more than ever before, this data can provide crucial insight for its conservation.
Earlier this month, Biologist Mike Mills presented SCCF’s research on the effects of hurricanes on Sanibel’s gopher tortoise population at the 46th annual Gopher Tortoise Council Meeting in St. Petersburg, Florida. The conference allowed the research to be shared with gopher tortoise scientists from around the southeast United States.
SCCF has been conducting annual gopher tortoise burrow surveys on Sanibel preserves since 2000. Frannie’s Preserve and C. R. Johnston Tract surveys began in 2000 while Dayton Preserve, Walker Preserve, and the Wulfert Gopher Tortoise Preserve began in 2007.
The average active burrow percentages across all five preserves stayed relatively consistent between the years 2007-2021 with a 12.1 percent increase of active burrows overall.
However, Hurricane Ian in September 2022 changed that consistency with a loss of 59.2 percent active burrows.
“In 2023, total active burrows increased by 9.4 percent, showing this species’ resiliency in the face of destruction,” said Mills. “Being such a long-term studied population, SCCF’s gopher tortoise research can provide a base model for other coastal or insular gopher tortoise populations around the southeast region that may be affected similarly by storms currently and in the future.”