December 13, 2010

Lake Martin, a Nature Conservancy Preserve in Lafayette, Louisiana

While we were in Lafayette, Louisiana to check out the Acadian Cultural Center and to get some real authentic Cajun food, we decided to swing by Lake Martin. This forested "lake" is a Nature Conservancy Preserve. It is home to the largest wading bird rookery in the United States, hosting at one time, up to 30,000 pairs of roseate spoonbills, ibises, egrets, and herons.

Unfortunately for Hilina, the lake did not have any spoonbills or herons around at this time of year. Their prime season is between February and June. The rest of the year, they are dispersed all across Louisiana. But, it was interesting to look around the swamp and check out the TNC visitor center.

See the little turtle basking on a cool December day?

The Nature Conservancy has built a 1/4 mile boardwalk out into the swamp and a 2.5 mile trail along the levee to the main area of the rookery. Lake Martin is also very popular with kayakers and canoeists, who can travel up the green sloughs and into the open water of the lake. This lake also has a very high number of breeding alligators.

One of the mysterious green sloughs to explore

However, things changed dramatically after Hurricane Rita rolled through the area in 2005. The hurricane changed the entire hydrology of the area, causing the lake level to drop significantly, as the water inputs instead drained into the nearby canals. As the lake level dropped, the alligators left, followed by the birds. The massive rookery was essentially abandoned the next year.

Only last year, engineers built a pumping system to pull water back into the lake from the canals to raise the water levels. The alligators are back and now so are the birds. At this stage there are now about 5000 breeding pairs of  birds. It is not up to pre-hurricane levels, but slowly but surely the birds are finding their way back for the breeding season.

A beautiful mural at the visitor center

Notice the correlation between alligators and birds? The naturalist at the visitor center explained that where there are alligators there are birds and when alligators leave, so do the birds. But, alligators do sometimes eat these birds, so why do they want to live there? It turns out the real threat to these birds are racoons and opossums. These animals can climb trees to feed on eggs and chicks. When water levels are low, it is also easier for them to get from tree to tree on the ground. But, they are also a primary prey item for alligators. So, alligators actually help protect these bird nests by controlling the 'coon populations.

A close up of the mural

That was an interesting natural history lesson for me. I think we need to find our way back to Louisiana sometime in the spring when the activity is really rolling. It would be so neat to see thousands of birds, alligators roaming about, and the flowers bursting out across the swamps. Next time, we'll also be sure to bring kayaks.

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