EPOW Ecology Picture of the Week -- Beware! 'Gator in Defensive Posture

Explanation: OK, now we're getting a bit too close, and he's getting really disturbed.

This is a mature and rather riled American alligator. We are in the baldcypress swamps and bayou country of coastal Louisiana, south of New Orleans. This is 'gator country. They own the top of the food chain here. And this specimen is warning us to back off.

Like crocodiles, alligators have a variety of displays and behaviors that signal various levels of agitation and threat. At first, they might just display an open-gape posture to expose those fearsome teeth. Then, if further perturbed, they may start to hiss.

If you persist in approaching, they then go into a body display mode, such as shown in these photos. If it has hauled out on land, the gator will arch its back and thrust its wide head upwards and give a couple of grunts.

This is a warning display. Note the very different, and far lighter, coloration of the underneath of its head. A threat display often serves to ward off attacks, and thereby avoid physical conflict. Many animals have behaviors that emphasize warning coloration when threatened; it is a wonderful example of convergent behaviors among highly disparate taxonomic lines.

OK, so we see the teeth, hear the hisses and grunts, and observe the head-raising displays. Time to back off! For the next step may be a sudden attack ... or the gator might choose to retreat, but if I were you, I wouldn't necessarily count on that.

Best to observe
from a distance ...

Information:
     Garrick, L. D., and J. W. Lang. 1977. Social signals and behaviors of adult alligators and crocodiles. American Zoologist 17(1):225-239.
Acknowledgment:
     My thanks to Dr. Jim Grace of U.S. Geological Survey's National Wetlands Laboratory for guiding me to this wonderful location ... and letting me approach this agitated alligator first (yeah, thanks for that, Jim!... kidding!).

EPOW - Ecology Picture of the Week