Florida has 44 native species of snakes, with only 11 of them being semi-aquatic water snakes. These water snakes have a threatened status of least concern according to the IUCN Red List, but unfortunately, populations are declining rapidly due to habitat degradation, pollution, changes in salinity levels, and removal by humans.
The majority of water snake deaths occur due to people misidentifying them as venomous snakes. Typically what they associate a water snake with is a water moccasin, which is the only venomous snake out of the 11 native water snakes, and 1 of only 6 overall venomous snakes in Florida. These numbers are so small in Florida’s snake population and yet they are one of the main reasons for mass snake executions. This unfortunate news is a prime reason educating the public is so important to protect native animals from being eradicated.
Non-Venomous Snakes
1) Florida banded water snake
- Scientific name: Nerodia fasciata pictiventris
- Meaning of scientific name: Banded sea nymph
- Family: Colubridae
- Other names: Banded snake, black water snake, blue snake, brown snake, common water snake, fasciated (water) snake, red-bellied water snake, southern banded water snake, wampum snake, water adder
- Average adult length: 22 to 40 in (56 to 102 cm)
- Maximum adult length: 60 in (152 cm)
- Threatened status: Least Concern
These snakes are notoriously confused with the venomous water moccasin due to being found in similar environments with slightly similar scale protrusions. The physical differences on the banded water snake vary from their long slender body, tail, and head. Although they look different when the snakes are relaxed, they begin to resemble each other when the banded water snake feels threatened. These snakes will often flatten their heads, creating a triangular shape, along with flattening their bodies and neck to appear larger and more intimidating to predators. These animals also have a defense mechanism of emitting an intense musk mixed with feces to avoid being eaten.
These semi-aquatic snakes become sexually mature around the age of 2 and breed during spring. After a gestation period of 79 days, the female births 9 – 50 live young, who appear paler with stronger patterns.
These animals can be found throughout Florida’s freshwater habitats, with some being found in more brackish areas. These animals were studied in California by ecologist Robert Reed, who saw these snakes eating non-native prey such as invasive mosquito-eating fish, frogs, toads, and tadpoles which backs the claim that these animals are extremely important for population control, especially in Florida where invasive species run rampant.
2) Brown water snake
- Scientific name: Nerodia taxispilota
- Meaning of scientific name: Flowing arrangements of spots
- Family: Colubridae
- Other names: Aspic, false moccasin, great water snake, pied water snake, southern water snake, water rattler
- Average adult length: 30 to 60 in (76 to 152 cm)
- Maximum adult length: 70 in (178 cm)
- Threatened status: Least Concern
These snakes are brown with 30 – 34 black squares flowing down their bodies with a triangular head that allows them to be misidentified as a venomous species in their environment, but brown water snakes lack venom and are harmless to humans.
These animals are typically diurnal hunters but have been recorded foraging in the evening hours. Their diet is mainly piscivorous (with studies showing 100% fish-filled guts) although they do have the occasional crayfish, tadpole, or frog. The brown water snake’s predation habits consist of ambushing prey and diving underwater for up to 30 minutes while hunting.
Brown water snakes have a lifespan of 6.2 years and only have a small list of predators ranging from birds, alligators, cottonmouths, humans, and raccoons.
The mating season begins in spring and generally ends in late August. The male will court a female by resting his head on her back until she allows him to connect cloacal openings. Females do not have a set gestation period as the pregnancies are not dependent on the collection of sperm but are rather based on their ovulation period.
Brown water snake females can hold sperm in their cloaca for long periods of time while they gather enough nutrition to suit them for pregnancy which is when they are unable to hunt. Live babies are born in clutches ranging from 20 – 60 and are immediately independent once birthed.
3) Florida green water snake
- Scientific name: Nerodia floridana
- Meaning of scientific name: Flowing through Florida
- Family: Colubridae
- Other names: Eastern green water snake, Congo water snake, Florida water snake
- Average adult length: 30 to 55 in (76 to 140 cm)
- Maximum adult length: 51 in (130 cm)
- Threatened status: Least Concern
Florida green water snakes are identified as being olive green, orange, or brownish in color with a very faint pattern that slowly fades as they age. These snakes can be commonly found in shallow slow-moving lakes, ponds, and canals throughout Florida. Their diets reflect that of most semi-aquatic snakes, feeding on fish and amphibians.
A Florida green water snake was caught in the Miami Dade area in 1992 and was dissected to find its stomach contents. The snake was discovered to have a non-indigenous African jewelfish, Hemichromis letourneuxi, inside its belly which was the first recording of this snake eating non-indigenous species which was an incredible discovery for a state which has been taken over by invasives.
These reptiles have a breeding season ranging from June to September and give live birth to 20 – 100 babies. The young are immediately alone after birth with no parental care and have a life expectancy of 9 years.
4) Black swamp snake
- Scientific name: Liodytes pygaea
- Meaning of scientific name: Fire-like
- Family: Colubridae
- Other names: Black swamp snake, mud snake, red-bellied mud snake, and swamp snake
- Average adult length: 22 in (56 cm)
- Maximum adult length: 24.5 in (62 cm)
- Threatened status: Least Concern
This harmless snake is both stealth and strike with its dark black back and super bright red belly. This elusive creature is nocturnal and very rarely seen by humans, but can be found just about anywhere with slow-moving currents, high vegetation, and clear water. Its feeding behavior includes swallowing prey whole and varies from leeches, small fish, and frogs, to small arthropods.
When this snake feels threatened, it releases a musk near its cloaca and attempts to coil. When coiling, these reptiles constrict their lungs and begin to suffocate, so it is rare you will see them reacting this way in defense or when capturing food.
Research at the Savannah River Ecology Lab has shown this species to be extremely tolerant of drought. Studies show that this snake is able to withstand a multi-year drought by aestivating within the dried wetland and using snake reproductive strategies of “adaptive anorexia” to sustain life, which had not yet been recorded being done by any other snake.
Another study in North Carolina showed how resilient these animals are post-drought. Unlike other snakes, these reptiles are able to feed during pregnancy to regain strength, which is crucial once the drought is over, since they lack nutrients and are unable to bring their young to full term. The black swamp snake is known for its income breeding and once in labor, will birth 2 – 15 live young.
5) Glossy crayfish snake
- Scientific name: Regina rigida
- Meaning of scientific name: Stiff smooth diver
- Family: Colubridae
- Other names: Eastern glossy swamp snake, Gulf swamp snake
- Average adult length: 14 to 24 in (36 to 61 cm)
- Maximum adult length: 31.4 in (80 cm)
- Threatened status: Least Concern
These glossy semi-aquatic snakes have chisel-shaped teeth which enable them to feast on the hard shell of their favorite meal, crayfish. Rather than coiling and suffocating their prey, they use their tail as a mechanism to hold the crayfish down to consume it, tail first.
This extremely timid snake is rarely seen by humans but can be found in a plethora of habitats with heavy vegetation, ranging from cypress swamps to roadside ditches. Since these animals are so elusive, there isn’t much known about these snakes, with herpetologists not even knowing if they are a rare snake or just difficult to find!
6) Striped crayfish snake
- Scientific name: Regina alleni
- Meaning of scientific name: Red stripes
- Family: Colubridae
- Other names: Striped swamp snake
- Average adult length: 13 to 20 in (33 to 51 cm)
- Maximum adult length: 4 ft (1.2 m)
- Threatened status: Least Concern
Striped crayfish snakes are often confused with glossy crayfish snakes due to similarities in diets, habitat, and even the way they look. Both snakes have glossy, dark, olive green or black dorsal scales with a yellow tinted belly. The defining differences between the two are that the striped crayfish snakes have one row of spots on the underside, whereas the glossy crayfish snake has a row of two spots.
Striped crayfish snakes are very secretive and can be found in highly vegetated swamps. They are rarely seen with limited data collected on them, but one study published in 1980 showed how successful striped crayfish snakes are in southern Florida. These reptiles were observed using water hyacinth to sit on top of the water to hunt for their preferred prey, crayfish. In Florida, water hyacinth is extremely invasive and multiplies rapidly. These rapid blooms give the striped crayfish snake lots of areas to hunt, allowing them to have a successful population.
7) Midland water snake
- Scientific name: Nerodia sipedon pleuralis
- Meaning of scientific name: A flowing serpent whose bite causes mortification
- Family: Colubridae
- Other names: Common water snake
- Average adult length: 24 to 42 in (61 to 107 cm)
- Maximum adult length: 55.3 in (140 cm)
- Threatened status: Least Concern
This species of non-venomous snake can be found in aquatic environments with shallow waters and sandy bottoms. They play a large ecological role in Florida’s environment as they are known to be prolific eaters with diets that mainly consist of fish, amphibians, mice, turtles, and other snakes. These reptiles are able to stay under the water for up to an hour and a half, anchored to vegetation to hunt, and also do not constrict but rather grab with their jaws and swallow their live prey quickly.
Midland water snakes are sexually mature at 21 months old and begin breeding in March. The male courts the female by rubbing his head down her body, giving a head jerk sporadically until she allows them to connect cloacal openings. Gestation lasts 3 – 5 months and they give birth to live clutches of 4 – 100 young. These snakes have a lifespan of 9 years in captivity with no data showing life longevity in the wild.
8) Plainbelly water snake
- Scientific name: Nerodia erythrogaster
- Meaning of scientific name: Red belly
- Family: Colubridae
- Other names: Agassiz’s water snake, copper-bellied, orange-bellied, red-bellied black snake
- Average adult length: 30 to 48 in (76 to 122 cm)
- Maximum adult length: 62 in (157 cm)
- Threatened status: Least Concern
Plainbelly water snakes are often spotted by humans as they are regularly out during the day basking, swimming, or hunting. These animals also spend a majority of their time in terrestrial habitats, unlike most semi-aquatic snakes. Although they spend the majority of time on land and consume tons of frog species, they still receive most of their nourishment from other aquatic animals such as fish and crayfish.
Plainbellys will hibernate in crayfish burrows, underground, or under rock piles until March. When they emerge, they begin mating rituals. This mating strategy occurs in “cords” (groups) in areas with shallow water with one female and up to several males wrapping around the female. The gestation period for this viviparous species is 3 to 4 months, with most clutches ranging from 2 – 55 offspring; the average being 18.
9) Rainbow snake
- Scientific name: Farancia erytrogramma
- Meaning of scientific name: Red stripes
- Family: Colubridae
- Other names: Common rainbow snake, eel moccasin, southern Florida rainbow snake
- Average adult length: 27 to 48 in (69 to 122 cm)
- Maximum adult length: 4 ft (1.2 m)
- Threatened status: Least Concern
This snake is known for its beauty in Florida as they have beautiful black iridescent scales, with three red stripes going down its body along with a yellow belly. These reptiles are extremely docile and are not known to bite; they will usually press their noses against the attacker or person handling them, with the occasional addition of released musk.
These snakes are nocturnal and have an interesting diet, feasting mainly on American eels, giving them the name eel moccasin. Rainbow snakes breed once a year starting from the age of 2 years old. They build a nest in loose soil or debris and lay clutches of 10 – 52 eggs, which they guard until they hatch. The young are then left without parental care and feed on tadpoles and earthworms until they are large enough to begin their eel hunt.
10) Saltmarsh water snake
- Scientific name: Nerodia clarkii
- Family: Colubridae
- Other names: Atlantic saltmarsh water snake, Gulf saltmarsh water snake, mangrove saltmarsh water snake
- Average adult length: 15 to 30 in (38 to 76 cm)
- Maximum adult length: 36.7 in (93.2 cm)
- Threatened status: Threatened
These saltwater snakes can be found along the coastal region of Florida, in mangroves and mudflats, in the wrack line on beaches, or hidden inside a crab hole. Saltmarsh water snakes are nocturnal hunters and feed exclusively on small fish they catch in shallow waters. This snake is federally protected on the East Coast of Florida, as its population has begun to decline due to pollution and environmental degradation.
Researchers in 2007 studied saltmarsh snake populations in two man-made lakes in Saint Petersburg, Florida. They collected data on 413 snakes from 2006 – 2007 until the area was sprayed with pesticides to control weed populations around the lakes. The study group dropped from 413 to 47 snakes in just two months, showing how sensitive these animals can be to changes in their environment.
Venomous Snakes
1) Florida cottonmouth
- Scientific name: Agkistrodon conanti
- Family: Viperidae
- Other names: Cottonmouth, cottonmouth moccasin, water moccasin, moccasin
- Average adult length: 30 to 48 in (76 to 122 cm)
- Maximum adult length: 74 in (188 cm)
- Threatened status: Least Concern
This heavy-bodied venomous snake can grow upwards of 0.6 – 1.2 m (2 – 4 ft) in length. Cottonmouths are sometimes mistaken for other non-venomous water snakes but are distinguishably different by their vertical pupils, facial pits, and eyes which are hidden under their prevalent brow ridge. Cottonmouths can also generally be seen fully exposed on the top of the water as they are very buoyant compared to other non-venomous snakes.
These reptiles are nocturnal hunters, feeding on fish, birds, eggs, other snakes, baby alligators, and turtles. The hunting strategy varies with the species they are catching; generally, they will hold fish in their mouth until the venom takes effect, but with mammals, the snake will usually bite and then release as this prey is known to bite back.
The cottonmouth breeding season begins in early summer and during this time the males will begin male-to-male combat to court females. The females will then birth 1 – 20 live young with no parental care. The juveniles then grow to be sexually mature at the age of 2 for males and 3 for females, with an expected lifespan of 10 years.
