Castles in the Ground
Gopher tortoises and their burrows play a key role in Florida’s ecosystem
An 18th-century explorer traversing the Florida wilderness wrote of “the dens of the great land tortoise, called gopher: this strange creature remains yet undescribed by historians and travelers.” Today, the gopher tortoise is a familiar sight in the Vero Beach area. No longer is it “undescribed.” On the contrary, scientific research and careful observation have given us insight into the lives of gopher tortoises. However, such knowledge has only increased our sense of wonder and appreciation for these “strange” yet endearing creatures.
Since that explorer — the naturalist William Bartram — became the first scientific writer to describe the gopher tortoise, scientists have learned that these tortoises are not only fascinating in their own right; they are important to the well-being of numerous other animals. The gopher tortoise is considered a “keystone species” or “umbrella species,” because so many other creatures benefit from its burrows.
Just a few examples are the burrowing owl, the Florida mouse and the gopher frog. More than 300 species of vertebrates “use or rely on the burrows for shelter or food,” notes the National Audubon Society Field Guide to Florida, making the gopher tortoise “the quintessential burrower … whose methodically constructed tunnels are the focal point of an entire mini-ecosystem.” If invertebrates are included, the number of guest species exceeds 400.
The gopher tortoise is the only tortoise species of the Southeast. Tortoises are often called “turtles” colloquially, and that is not inaccurate; “turtle” is the broader term, while “tortoise” refers to a type of turtle that lives on land instead of in water.
The shell of a gopher tortoise is made of bone and is fused to the spine and the ribs; scale-like areas of keratin, called scutes, grow along parts of the shell. The shell is like a suit of armor for the tortoise — the animal will withdraw into the shell for a sense of security — but at the same time, the shell is also part of a tortoise’s body. For such proverbially slow-moving creatures, this is a valuable protection. However, the key survival strategy for gopher tortoises is burrowing. And it is their amazing burrows, which Bartram called “castles,” that make them so important to the Florida ecosystem.