Studying Alligators – A Photo Essay

An important part of ensuring an ecosystem persists is understanding it and its components. So, in order to further our understanding of the Okefenokee Swamp ecosystem, researchers Dr. Kimberly Andrews and Master’s student Kristen Zemaitis from the University of Georgia, Odum School of Ecology, have set out to learn about one aspect of the ecosystem; female alligators. This photo essay shows how researchers are learning about these alligators.

The trained team catching and working on the alligators in the images includes members of the Georgia Sea Grant Coastal Ecology Lab, Okefenokee Swamp Park, and collaborators.

Catching and Restraining an Alligator

The team uses a catch pole to pull the animal onto land so they can collect data. Then, members of the team hold the alligator in a forward position while additional members approach from behind, slip a top-jaw rope on, then restrain the animal using their own weight. The animal’s eyes are then covered to keep it calm, and the jaw is taped shut to restrict its biting ability. These methods keeps the alligator from injuring itself, or members of the team.

Collecting Animal Data and Placing Identifiers

Once the alligator is safely restrained, lidocaine is administered to numb an area for a radio transmitter to be installed. The transmitter will allow researchers to track the animal’s movements throughout the swamp. Once the area is numb, a drill is used to create small holes in the osteoderms (bony plates) where the radio tracker will be affixed. Pieces of the tail scutes are removed so that the animal can be easily identified by observing it from a distance in the future, and the collected scute provides a genetic sample. A tail tag with a unique number is also affixed to the animal to aid in future identification. Morphometric data (measurements) of the animal are also collected. These measurements will help researchers understand if the animal is growing, or at least maintaining, its current size in the future.

Releasing an Alligator

Once researchers have collected all the animal’s data, and marked it for future identification, it is time to release the animal. The team removes the jaw restraints except for a small amount of tape that will temporarily hold its jaw shut while researchers move away. A rope is affixed to this tape, so it can be pulled off once everyone is safely away from the animal.  Researchers then simultaneously jump off the alligator and quickly move away, taking the towel over the animals’ eyes with them. Finally, the tape over the animal’s jaw is pulled off with the rope, and the animal slips back into the swamp.

Video of the Process

You can see additional snippets of how the trained team of biologists safely captures and restrains an alligator for data collection, takes morphometric (or measurements) data, and releases an alligator in this short video.

Collecting Location and Behavior Data

After installing radio transmitters, researchers can begin to collect data on the animals. By tracking the animals and monitoring their behavior, researchers can understand what parts of the swamp the alligators use and for which purposes. For example, they may learn where in the swamp an alligator’s territory is, where it feeds, where it has its nest, and other information.

Camera traps allow the researchers to observe animal behavior, so researchers mounted them on trees to record alligator activity. Maintenance of these cameras includes changing batteries, swapping out full memory cards, and moving cameras to areas of alligator of activity.

Tracking of the animals is accomplished using a very high frequency (VHF) antenna and radio receiver. Researchers set the receiver to the animal they’re looking for by using a numerical code from the radio tracker on that animal. They then point the antenna around the swamp, and listen for the beeps from the receiver to get louder as they point towards the direction of the alligator. They paddle in the direction of the loudest beeps. Upon finding the alligator, researchers confirm that the animal is alive and healthy via visual inspection, and take notes on its location and behaviors. This data is combined with the camera trap information to create a more complete picture of the animal’s use of the swamp.

Analyzing and Applying Results

Data collection will continue for a few years to help create a holistic picture of alligators’ use of the swamp. When data collection is completed, researchers will analyze the information they’ve collected, and will then have a much better understanding of alligator’s habitat use. This information can then be applied by land managers at the Okefenokee Swamp and beyond to ensure alligator’s habitat needs are met and their populations in the swamp continue to thrive.