Monday, April 18, 2011

Of Snowy Egrets and Alligators

Our Bryan Champagne-led swamp tour continued. The swamp tour site, Cypress Island/Lake Martin Swamp, a backwater swampy area cut off from the main Atchafalaya River Basin Swamp is a popular spot with locals for good fishing and alligator watching and is one of the largest avian sanctuaries in North America.

"In 1950 the State of Louisiana and land owners around Lake Martin Swamp entered into a lease agreement that allowed the state to build and keep up a levee encircling Lake Martin to maintain a deeper constant water depth for the purpose of creating a public hunting and fishing preserve. This levee stopped the seasonal water fluctuations that are characteristic of backwater swamps turning a large portion of this swampy wetland area into an impoundment. As an added bonus the im-poundment created an environ-ment very attractive to alligators and wading birds. The wading birds now utilize the area for feeding, roosting and rookery purposes. This area supports one of Louisiana’s largest populations of alligators of over 10 feet long" (lake martin webpage).

Bryan had a good eye for locating some of the main residents of the swamp, so our experience with alligator watching was off to a good start.

"During early spring (late February for Louisiana), tens of thousands of great, snowy (photo, right), and cattle egrets, Roseate spoonbills, herons and other birds nest on the swampy perimeters of the lake and stay until summer. They choose the bald cypress and gum tupelos for their proximity to local crawfish fields and the shallow water and alligator habitats. Alligators serve a purpose but they also pose a threat.

“'Wading birds select nesting sites over water patrolled by alligators because the ’gators ward off more predacious mammals such as raccoons, possums, minks and rats,' writes Nancy Camel in The Nature of Things at Lake Martin. 'However, alligators also consume displaced birds and have been known to strike button-bushes, knocking chicks out of the nest.'

"This relation-ship makes for great reptile viewing as well as bird watching.

"Other visiting birds at Lake Martin include white ibis, storks, anhingas, warblers, night herons, owls, woodpeckers, blackbirds, ducks, hawks and migrating birds such as orioles, summer tanagers and painted buntings.

“'The heronries of the southern portion of the United States are often of such extra-ordinary size as to astonish the passing traveller,' wrote naturalist and avian artist John James Audubon when living in Louisiana.

"Snowy egrets breed once a year, and females lay three to five greenish blue eggs that hatch in three to four weeks. Their platform-like nests are built primarily of twigs and are located in trees (about seven feet, more or less, above the ground) or even on the ground.

"As with other herons, the crudeness of the egret's nest, the elliptical form of the egg, and other signs suggest to some scientists that these birds are one of the lower forms on the scale of bird life, not far removed from the reptiles, when one reckons in eons of time" (Cheré Coen,

We thought it was interesting just how closely the alligator and the snowy egret are connected.

The last resident we met was this fellow (below). Bryan noted that he had been keeping track of this guy for about eight years. From this view, he looked much like any other alligator to us.

But when we saw him from this side (right), we were stunned. Bryan thought that the severe jaw injury was possibly due to an encounter with another gator, but thought it was more likely the result of being injured by the blades of fishing boat's outboard motor.

An interesting day at the swamp.

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