Sunday, July 4, 2010

American Alligator

Juvenile
To celebrate the 4th of July, and the fact that I just got back from South Carolina with more animal pictures than I know what to do with, we're going to talk about the American Alligator! There are only two extant species of Alligator, and the American is the largest. They live in freshwater swamps in the South Eastern United States and can grow up to 15 feet in length, though even larger specimens have been recorded. Alligators and other Crocodylians are very old species, with their ancestors appearing during the mesozoic era and surviving the great extinction that finished off the dinosaurs.


American Alligators are opportunistic predators, and will eat just about anything. There have been documented human killings, and since the statistics began in 1948, there have been 20 killings in the state of Florida. While that number does seem a bit chilling, overall humans are not a major part of the Alligators' diet. They eat birds, reptiles, mammals, insects and carrion. Alligators do not need to feed daily, and when the temperature cools down enough (below a around 73 degrees) they stop feeding all together and subsist on their stored up reserves. They can go for weeks at a time without feeding. American Alligators are very quiet hunters, moving towards prey with all but their eyes and nostrils submerged, and then springing forward in one fast movement to capture their meals. They are wonderful swimmers, but awkward on land. Alligators cannot chew their food, so they need to either consume meals small enough to swallow whole, or they have to tear off pieces of their kill.

Adult!
As far as reproduction goes, males attract females by bellowing. Interestingly, American Alligators do not have vocal cords. Despite this, the bellows can be heard over a mile away. Females build nests on land that protect and incubate her eggs, and she guards it vigilantly during the incubation period. Upon hatching, the young alligators alert their mother, who then has to dig them out of the nest. Juveniles remain with the mother for several months. In another interesting fact, a new study shows that female American Alligators choose to stay with the same breeding partner 70% of the time.

Feeding Time!
A question that I've been asked a handful of times is "What is the difference between an Alligator and a Crocodile?" Well, there are a few visible cues. First, the Alligator has a more broad, square head, while the Crocodile's is more pointy and triangular. The teeth can also be a big giveaway. The lower teeth of an Alligator fit snugly into their upper jaw, so only the top teeth might stick out. Crocodile teeth interlock, so both the upper and lower sets are visible externally. A less visible difference is the fact that Alligators stick pretty much exclusively to freshwater, where Crocodiles are more tolerant to salt water due to glands that allow them to filter out all of the salt. These are of course just a handful of difference between the two, but the jaw and teeth differences should be helpful in determining what you are looking at.

No comments:

Post a Comment