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Are there Indigo Snakes on Cayo Costa?

December 6, 2023
Indigo Pine Island

The SCCF Pine Island Sound Eastern Indigo Snake Project began monitoring and researching the remaining populations of these rare and protected eastern indigo snakes (Drymarchon couperi) on the islands of Pine Island Sound in 2012.

Unfortunately, they were found to be extirpated — or no longer in existence — on Sanibel and Captiva early on, but there was evidence of a remaining population on Pine Island, North Captiva, and Cayo Costa.

Both Pine Island and North Captiva were found to have small, but reproducing populations that were able to be studied. However, Cayo Costa, which has the largest non-bisected natural habitat of the five main islands of Pine Island Sound, produced the lowest success.

“Roads and traffic, which are not an issue on Cayo Costa, are the usual cause of eastern indigo snake decline and loss from an area,” said Wildlife & Habitat Management Director Chris Lechowicz. “Instead, the main reason for their rarity on Cayo Costa was concerning and was thought to be due to the feral hog population that has plagued the island for decades.”

It is believed that the hogs were brought there by locals to hunt many decades ago. The presence of the feral hogs had drastic implications for the flora and fauna of this mostly undeveloped island, which was designated as the Cayo Costa State Park in 1976. The hogs were finally eradicated in 2018 by the state park system.

By removing the hogs, it was thought that would allow many species, including eastern indigo snake, to increase their numbers if enough individuals survived.

SCCF will be returning to Cayo Costa this season to resume surveys that lapsed in 2016, due to the lack of samples.

There have been undocumented reports of indigo snakes since then, but there has been no definitive proof of their continued existence. These magnificent snakes face many threats throughout their range and are in major decline throughout most of their range.

“Viable island populations are even rarer these days, so it is very important that we document all the information we can and educate people about this gentle giant that is disappearing quickly,” said Lechowicz.

If you see an eastern indigo snake on any island in Pine Island Sound, please report it to


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