Are There Sea Snakes In Florida?

Olive Sea snake, Disteira major in Bundaberg, Great Barrier Reef,Queensland. It can grow up to six feet long and weigh up to six and a half pounds.
© Sahara Frost/

Written by Hannah Ward

Published: May 8, 2022

Share on:


The majority of Florida is situated on a peninsula between the Gulf of Mexico and the Atlantic Ocean.  With 1,350 miles of coastline and many barrier islands, it’s not surprising that there are thousands of animals that call the water around Florida their home.  But what about snakes?  There are more than 50 different species of snakes in Florida, and many of them are water snakes.  But are there sea snakes in Florida?  Join us as we find out!

What are Sea Snakes?

Sea snakes have eel-shaped bodies, which make it easier to swim but impossible to move on land.

©Sahara Frost/

There are 69 species of sea snakes which are all from the subfamily Hydrophiinae in the Elapidae family group, and the majority of them are highly venomous.  Almost all sea snakes are completely aquatic and are unable to live or move on land – with the only exception being sea kraits.

To make them suited to their watery habitat, sea snakes are uniquely adapted.  All sea snakes have flattened paddle-like tails and bodies which appear to be more eel-like.  These snakes also have an excellent sense of smell while underwater. They have unique nostrils that contain valves made from spongy tissues so that they can prevent water from entering them.  Additionally, their lung is large and runs almost the entire length of their body. This helps them to hold their breath for a long time during deep dives.  Sea snakes can remain underwater for anything from ten minutes to several hours.

Sea snakes have also adapted to the salt in their environment.  They often ingest a lot of seawater. This means that they need to have an effective way of removing the excess salt from their bloodstream.  Sea snakes are able to do this through a set of glands that are located around their tongue sheath. These glands mean that they can remove excess salt through their tongue action.  Although it might seem surprising, sea snakes still need to drink fresh water to survive.  As a result, many populations remain near the shore, particularly around estuaries, to achieve this.

Are there Sea Snakes in Florida?

Black Banded Sea Krait Swimming

There are no sea snakes in Florida as they cannot reach the Atlantic Ocean.

©Ethan Daniels/

There are no sea snakes in Florida.  This is because there are no sea snakes in the Atlantic Ocean.  The lack of sea snakes in the Atlantic Ocean is down to the formation of the Isthmus of Panama and the temperature of the South Atlantic Ocean.  Read on to find out exactly how this prevents sea snakes from existing in Florida.

Why There are No Sea Snakes in the Atlantic Ocean

The main reason that there are no true sea snakes in Florida is that there are no sea snakes in the Atlantic Ocean.  The lack of sea snakes in the Atlantic has long been pondered over as, theoretically, the warm, tropical waters of Florida and the Caribbean would be the perfect habitat for them.  However, the real reason is thought to go back several million years. The sea snakes that we know today first evolved 6 to 8 million years ago in southeast Asia’s Coral Triangle. However, the majority evolved 1 to 3 million years ago.

The Isthmus of Panama is a narrow bridge of land that formed around 4 million years ago and joined North and South America. This effectively closed the channel between the Atlantic and Pacific oceans.  Many sea snakes didn’t evolve and cross the Pacific ocean until after this was formed.  This meant that the only other access would be to swim around the land barrier. In this case, the bottom of Africa and the bottom of South America from the Indian and Pacific oceans, respectively.  However, sea snakes cannot survive in water that is less than 18°C, so the cold water of the South Atlantic means that they can’t survive the journey.  These factors mean that the Atlantic Ocean is entirely out of bounds for sea snakes.

So why are there Snakes near the Coast?

Gulf Salt Marsh Snake

The saltmarsh water snake can be found along the coast of Florida in habitats with brackish water.

©Jay Ondreicka/

It might seem somewhat surprising to hear that there are no sea snakes in Florida as there are snakes that live in shallow coastal water and around bays, estuaries, saltmarshes, and mudflats.  However, these are typically saltmarsh water snakes.  Saltmarsh water snakes are non-venomous, semi-aquatic snakes that live in many of these habitats in and around the Florida coastline, feeding almost exclusively on small fish and frogs.  They also occur in the Florida Keys and around many barrier islands.  Saltmarsh water snakes are 15 to 30 inches long and can be gray, brown, or tan, with stripes down them.  They are not sea snakes as they are members of the Colubridae family group. They also lack paddle-shaped tails. Additionally, saltmarsh water snakes can come onto land where they often inhabit crab burrows along the shoreline.

There are also some other species of snakes that can sometimes be seen around the coastline and the barrier islands. However, again, these are semi-aquatic snakes rather than sea snakes.  One such snake is the eastern diamondback rattlesnake which is a venomous pit viper that is widespread throughout Florida.  Eastern diamondback rattlesnakes typically inhabit pine flatwoods, cypress swamps, and salt marshes.  However, they are found throughout the Florida Keys and many barrier islands and often swim between the islands.

Could there Ever be Sea Snakes in Florida?

At the moment, there is no chance of sea snakes reaching Florida. This is because the seas are just too cold for them to survive the journey.  If the oceans continue to warm up, then there is the possibility for sea snakes’ range to expand further south. However, it is still not likely any time soon.  Additionally, even if the water is warm enough for them, the other limiting factor allowing them to progress around the coastlines up towards Florida is the availability of fresh water for them to drink.  Although sea snakes rely on freshwater from rivers and streams entering the sea to drink, rainfall also plays a part.  This is because when there is enough rainfall, freshwater sits at the ocean’s surface before it mingles with saltwater. Therefore, sea snakes can also drink at the surface.

Despite the question of whether sea snakes can ever eventually make it to Florida, it is interesting to note that ancient sea snakes once existed in the Atlantic Ocean.  Ancient sea snakes from the family group Palaeophiidae lived 33 to 70 million years ago.  Before the sea temperatures dropped dramatically, they lived around the North American coastline.  Fossilized remains have been found in Georgia, Maryland, and Virginia.

Discover the "Monster" Snake 5X Bigger than an Anaconda

Every day A-Z Animals sends out some of the most incredible facts in the world from our free newsletter. Want to discover the 10 most beautiful snakes in the world, a "snake island" where you're never more than 3 feet from danger, or a "monster" snake 5X larger than an anaconda? Then sign up right now and you'll start receiving our daily newsletter absolutely free.

Share this post on:
About the Author

Hannah is a writer at A-Z animals where her primary focus is on reptiles, marine life, mammals, and geography. Hannah has been writing and researching animals for four years alongside running her family farm. A resident of the UK, Hannah loves riding horses and creating short stories.

Thank you for reading! Have some feedback for us? Contact the AZ Animals editorial team.