The ‘seasick’ crocodiles of South Florida

This past holiday season, I listened to the iconic “You’re a Mean One, Mister Grinch,” and was struck by the classic line: 

“You’re a vile one, Mr. Grinch

You have termites in your smile

You have all the tender sweetness of a seasick crocodile, Mr. Grinch

Given a choice between the two of you I’d take the seasick crocodile!”

It got me thinking. The joke, of course, is that crocodiles are famously fond of water and so a seasick crocodile is in for a very, very rough day. But in reality, “seasick” crocodiles are actually kind of a thing: The American crocodiles of the Florida Keys are facing sea level rise and saltwater intrusion, which is causing habitat loss; you could say they have good reason to be “seasick.” 

Crocodile Lake: home to crocodiles

Many of the scaly individuals from this ancient species make their home near Crocodile Lake, located in Key Largo in the Upper Florida Keys and within the Florida Keys National Marine Sanctuary. This area is so ecologically important it’s been protected twice-over: first as a National Wildlife Refuge and then as a Wildlife Management Area (WMA) in the Florida Keys National Marine Sanctuary. 

The Lake and surrounding refuge contain a wide variety of habitats, such as a tropical hardwood forest, rugged mangroves and a brackish salt marsh. The area’s titular residents, the American crocodile, are an endangered species that dates back millions of years.

Found throughout Central America and Jamaica, Cuba and Hispaniola in the Caribbean, this large predator’s range extends at its highest to South Florida, which is the only place in the Continental United States where the species lives. Typically, adults grow to around eight to 11 feet in length and survive on a diet of crabs, birds and fish. While these armored giants are fearsome predators, sadly they are struggling to survive in the Keys. 

Since being listed as an endangered species in 1975 and a threatened species in 2007, Florida conservationists have made great strides to increase their numbers. However, around 10 years ago, the number of nesting sites started to flatline on Key Largo. Sea level rise, nest site erosion and habitat loss have been the primary drivers of this slowdown in the crocodile’s recovery. Sea level rise has caused water to intrude on their nursery habitat and nesting areas, which have negatively impacted hatchling survival and nesting rates. Nearby boats have also damaged much of the seagrass and marshlands in the Keys, degrading the value of this critical habitat. 

Despite rapidly declining environmental conditions in the Keys, the Sanctuary and Refuge managers remain dedicated to protecting the American crocodile and its habitat.

A plan to keep Crocodile Lake full of crocodiles

Water pollution, climate change, overfishing and overuse have really taken a toll and the National Oceanic and Atmospheric Administration (NOAA) has taken notice. To improve the ecosystems that the Keys contain, the agency has recently proposed its Restoration Blueprint, which outlines a series of policies and recommendations to restore the ecosystem’s resilience against human impacts.

For Crocodile Lake, the news is promising.

Under the current policies, there is a 100’ “no-entry” zone across the entire Eastern shoreline from March 1 to October 1. However, this still allows a four-month period where people can disrupt the crocodiles’ habitats. Clearly, this is not protective enough, and NOAA aims to make changes. Crocodiles rely on shorelines and shallow water to nest and lay their eggs. NOAA has proposed that the “no entry” zone along the shoreline should be enforced year-round. This will ensure that the crocodile’s habitat remains continuously undisturbed and will give them the breathing room they need. 

Given how impaired South Florida’s coastal ecosystems are in the Keys, it is important to preserve all the habitat we can for these incredible creatures. Crocodile Lake exemplifies many of the benefits that will come from the updates proposed in the Restoration Blueprint. The proposed regulations, in part, will help support the ecosystem that these crocodiles call home, ensuring that they keep their foothold in the continental U.S. and remain an iconic species of the Florida Keys.