Marine Life in the Florida Keys

Marine Life in the Florida Keys is incredible. There is a variety of sea life that lives in the Florida Keys. There are animals, coral, jellyfish, turtles and more. The marine life that is found throughout the Keys is a very interesting and beautiful sight for anyone to enjoy. I had the pleasure of visiting the Keys and seeing this first hand.

Marine Life Animals

marine life lobster or crawfish

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The Keys hold crawfish, or spiny lobsters, that are a treat to the residents and visitors alike. Spiny lobsters are related closely to shrimp, crabs, and other 10-legged crustaceans. They have adapted to bottom-dwelling, and adult lobsters have a tough outer shell ( or exoskeleton),  a tail that enables them to have a quick get away by swimming backwards, and long antennae for defense. Lobsters are nocturnal and very mobile creatures that migrate, at times, long distances in lines that are known as  queues. Lobsters can reach up to three feet, sometimes more in overall body, as well as live for at least 15 years. The  Florida Keys commercial lobstering business generates over $5 million annually to the local economy. There are a lot of regulations in place to help keep this business profitable while keeping the creatures population in mind as well.




marine life dolphin

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There is a part of the Florida Keys National Marine Sanctuary that is home to a resident group of bottlenose dolphins. Because of this, a lot of businesses choose to hold dolphin tours in this area, which can lead to stress for the dolphins. To help reduce this stress to dolphins in the sanctuary, several organizations joined together to create the Dolphin SMART program. This program recognizes businesses that promote responsible viewing of wild dolphins. This helps to protect the dolphins well being while still allowing an encounter for those visiting.






manatee marine life

Florida manatee (Trichechus manatus latirostris) playfully holding a diver, Crystal River, west-central Florida, U.S.A.

In the winter, Keys residents and visitors often see West Indian manatees swimming leisurely along the edges of the water or shoreline. These large, gentle herbivores are found in shallow, slow-moving waters that are full of seagrass beds or vegetation. These beauties eat up to 150 pounds of plants each day, and manatees usually weigh somewhere between 800 and 1,200 pounds and reach about 10 feet in length. Unfortunately, due to human negligence and interference, these beauties are on endangered species list. They are often killed by boaters.








Lion Fish marine lifeThis fish is hard to mistake with distinctive reddish and white stripes, menacing spines, and gracefully flowing fins. There are few fish that show similar beauty, mystery, and danger of the ocean like the lionfish does. In Florida Keys National Marine Sanctuary, divers here are being encouraged to remove as many lionfish as possible, as they are a danger to the waters. There recently was a co-hosted series of lionfish roundups, offering cash and prizes for divers bringing in the biggest catches. These derbies also helped to educated divers on how to safely handle and eat these pesky marine invaders. The lionfish has a noticeable lack of predators, rapid reproduction, voracious appetite, and grow quickly. This all spells trouble for the balance of ecosystems and fisheries, that it invades.




marine life turtles

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There is a total of seven species of marine turtles, out of that seven, five are found in the waters off the Florida Keys. These 5 are the loggerhead, hawksbill, green turtle, kemp’s riley, and the leatherback turtle. These reptiles have adapted well to life in the marine world. The male sea turtles spend their entire lives in the ocean, never leaving the sea. The adult females, however, do leave the waters to beaches on land in order to lay their eggs. They often travel long distances between areas where they have fed and where they decide to nest. Mature males and females of the leatherback turtles can grow to be as long as six and a half feet and weigh almost 2,000 pounds. The leatherback is the only one of any sea turtle that lacks a hard, bony shell. The green turtles are the largest turtles with hard shells, with the adults growing to  possibly larger than three feet long and weighing around 300-350 pounds. All seven of marine turtles species are listed as either ‘threatened’ or ‘endangered’ under the Endangered Species Act.

marine life jellyfish

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Jellyfish are no one’s favorite creature, especially if you have been stung by one. Fortunately, the most common marine life jelly, or jellyfish, in the Florida Keys, the Cassiopeia’s tend to give only a mild sting. Tentacles from this species are upward facing, which looks like a jellyfish swimming upside-down. These are easiest to find among the mangrove, giving them a nickname of the ‘mangrove upside-down jellyAs they are common  The cannonball jelly is yet another species found in the Keys’ waters. This one also tends to have little or no sting. Some have said that they don’t feel a sting at all. I still recommend being cautious if you’ve never dealt with this species. This is the same jelly that is often found washed up on shorelines along Florida’s Atlantic coast. Another common springtime jelly is the sea thimble. Sometimes, swarms of theses appear in the Keys close to April and May, and they can look like an oil slick from far away.  Though not a true jelly, the Portuguese man o’ war can make it’s way into the Keys and South Florida during the winter when strong winds come in from the south.

marine life coral

Photo was taken of hardened coral on Sombrero Beach

Coral in the Keys.

Coral marine life in the Keys is beautiful. Most don’t know that coral is actually an animal, not a plant. With their hardened surfaces, corals are sometimes mistaken as being rocks. I had this exact experience for a brief moment, walking along the shoreline on Sombrero Beach. There was a large patch of hardened coral, pictured on the right, that we explored while visiting. Because coral attached to the seafloor, by it’s roots, they are often mistaken for plants. However, unlike rocks, which are dead, corals are alive. Unlike plants, corals do not make their own food. The branch or mound that is known as a coral is made up of thousands of small animals that are called polyps. The polyp is an invertebrate that is no bigger than a pinhead and only reaches a foot in diameter. Every polyp has a saclike body and a mouth that is surrounded by stinging tentacles. If a coral reef is compared to a busy city, then  compare a coral colony to a single apartment with a ton of rooms and hallways that hold homes for different marine species. In the Florida Keys is the home of the third largest living coral reef system in the world. Pretty incredible right? This tract in the Keys extends from Soldier Key located on Biscayne Bay in the Tortugas Banks. The track stretches for nearly 150 miles in length and is about four miles wide.


Marine Life Plants in the Keys

marine life plant

photo of mangroves in Marathon Fl

There are around 80 different species of mangrove trees total. These trees all grow in areas that have low-oxygen soil, where the slow-moving waters create fine sediments to accumulate. Mangrove forests grow only at subtropical and tropical latitudes that are near the equator due to the fact they cannot stay in freezing temperatures.  Most mangrove forests can be recognized due to their dense tangle of prop roots that make the trees look as if they are  to be standing on stilts above the water. This tangle of roots allows the trees to withstand the constant rise and fall of tides. This  means that a lot of mangroves get flooded around twice per day.  The roots also help to slow the movement of tidal waters, which causes parts to settle out of the water. This builds up the muddy bottom of the trees. Mangrove forests help to stabilize the coastline. This reduces erosion from tides, waves, currents, and storm surges. The complicated root system of mangroves helps to make these forests attractive to fishes and other organisms that may be seeking food and shelter from predators.