Friday, August 3, 2012

“Gopher” the Gold- The Story of a True Olympian

A Florida gopher tortoise (Gopherus polyphemus) strolls the GTM NERR grounds.
In the midst of the 2012 summer Olympic Games, we present to you a true Olympian residing right here in the GTM NERR…the Florida gopher tortoise! Are you surprised? We realize that if you were asked to name a creature that lives up to the adjective ‘Olympian’, the Florida gopher tortoise may not be the first creature you think of- in fact, chances are it may not be on your mental list at all. Our goal today, however, is to challenge you to look a little more closely at this unassuming animal and how well it measures up to the title.

The word Olympian has many different definitions, among them is ‘exceptional’, ‘remarkable’, and even ‘far beyond what is usual in magnitude’. Are you unsure about how these apply to the Florida Gopher Tortoise? Bear with us just a moment longer while we explain. The gopher tortoise is known as a ‘keystone species’ in Florida. A “keystone species” means that it has a disproportionately large effect on its environment relative to its abundance. Just as the top center stone in an archway prevents the structure from collapsing, the Florida gopher tortoise also plays a critical supporting role to the GTM NERR environment. There are two significant ways the Florida gopher tortoise impacts in our environment:
  • Returns leached nutrients to the soil and promotes seed dispersal through digging and grazing
  • Provides shelter for more than 350 other wildlife species, some of which are incapable of building their own

Florida gopher tortoises dig burrows ranging from 10 to 30 feet long in sandy soils for shelter. These burrows become a safe refuge protecting many creatures from storms, lightning, predators, and fires. A variety of species have been recorded that seek out the Florida gopher tortoise burrows for shelter; the list includes marsh rabbits, coachwhip snakes, cotton mice, raccoons, opossums, and armadillos. Some animals are known to be fully dependent on the carefully built burrows, such as the Gopher Frog and Florida Mouse, which have been known to spend their entire lives within it, creating a microhabitat. As you can see, the Florida gopher tortoise is truly remarkable, far beyond what is usual – the Olympian of the GTM NERR.

The Florida gopher tortoise is a "keystone species" whose ecological impact on many other species is great.

As with any Olympian, however, the Florida gopher tortoise is up against some tough competition. It is slow to reproduce, females not reaching sexual maturity until 10-15 years of age, and then only laying around 6 eggs each year. This coupled with auto traffic, human encroachment, and a number of predators have led the species to decline. Due to its importance and this decline, in Florida, the gopher tortoise is listed as a threatened species and its burrow is protected.

To help monitor and protect the Florida gopher tortoise, GTM NERR management practices and conservation measures include:
Control burning in the tortoises’ fire-dependent communities (tortoises can escape fire by remaining in their burrows)
  • Gathering facts on population status and documenting population trends on managed lands;
  • Conducting surveys of active and inactive burrows and mark locations by GPS
  • Learning about short- and long-term effects of management practices to share with partner agencies and land managers
During the 2011-2012 survey, which was recently completed, we recorded 232 Florida gopher tortoise burrows on the beach and dune areas of the GTM NERR, of which 192 were actively being used by the tortoises.  On the peninsula we recorded 247 burrows, of which 148 were actively used by the tortoises.  These numbers show the promise of a fairly stable and even growing population in some areas, but more is yet to be done- especially as we continue to study commensals, or dependent species.

Opossum captured by motion activated camera.
 Bobcat scent marking a burrow.

We would be amiss if we did not take a moment to thank our volunteers who help to make this research possible. For the 2011-2012 survey, 25 dedicated GTM NERR volunteers contributed more than 375 hours surveying the peninsula. An Olympic sized THANK YOU goes out to each of them.

To learn more about the Florida gopher tortoise research and conservation efforts by the GTM NERR, visit us at

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