Blackie: Male, hatched in the wild. He came from a facility in the Florida Everglades and arrived at the Zoo on September 10, 1956. At more than 50, Blackie is one of the oldest animals in the Zoo.
American alligators are generally gray or black in color and have a broad, flat head and rounded snout, along with short sturdy limbs, webbed feet and sharp claws. Their bottom teeth aren't visible when the mouth is closed.
Reproduction
They lay 20-60 eggs in a mound of mud, humus and rotting vegetation near the water's edge. Incubation averages 65 days. After the eggs hatch, the mother may stay with her young for one to three years.
Alligators have no chromosomes to determine sex. Sex is determined by incubation temperature. Less than 30 degrees Celsius produces females, more than 34 degrees Celsius produces males.
Behavior
Alligators spend much of their day basking on shores of rivers and lakes hidden in vegetation.
They have a complex system of social communication. This includes seven different identified vocalizations, subsonic vibrations and a series of behaviors such as jaw slapping on the waters surface. These all combine to communicate territory between males, indicate gender in areas of poor visibility and the alarm calls of hatchlings will bring adults to the rescue.
Adaptations
The American alligator's broad, heavy head is an adaptation to living in heavily vegetated swamps--a heavy head has more momentum to help catch prey by smashing through thick vegetation.
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