by Rick O'Connor | Jan 19, 2018
In the last article, we discussed what phytoplankton are, what their needs were, and their importance to marine life throughout the Gulf and coastal estuaries. In this article, we will discuss the different types of phytoplankton found in our waters.
The spherical shape of the centric diatom.
Image: Florida International University
Marine scientists interested in the diversity and abundance of phytoplankton will typically sample using a plankton net. There are a variety of different shapes and sizes of these nets, but the basic design would be funnel shaped with a sample jar attached at the small end of the funnel. The plankton net would be towed behind the research vessel at varying depths for a set period of time. All plankton collected would be analyzed via a microscope. According to the text Identifying Marine Phytoplankton (1997) there are at least 14,000 species of phytoplankton and some suggest as many as 120,000. Most of these, 12,000-100,000, are diatoms, one of five classes of marine phytoplankton. The majority of the phytoplankton fall into one of two class, the diatoms and the dinoflagellates.
Diatoms are typically single celled algae encased in a clear silica shell called a frustule. The frustule can come in a variety of shapes, with or without spines, and many resemble snowflakes – their quite beautiful. They are found in the bay and Gulf in great numbers, as many as 40,000,000 cells / cup of seawater. They are the dominate phytoplankton in colder waters and are most abundant near upwellings. These are the “grasses of the sea” and the base of many marine food webs. When diatoms die, their silica shells sink to the seafloor forming layers of diatomaceous earth, which is used in filters for aquariums and oxygen mask in hospitals.
Dinoflagellates differ from diatoms in that they produce two flagella, small hair-like projections from the algae that are used for generating water currents and movement. Their shells are not silica but layers of membranes and are called thecas. Some membranes are empty and others contain different types of polysaccharides. Dinoflagellates are more abundant than diatoms in warmer waters. There are about 2000 species of them. One type, Noctiluca, are responsible for what locals call “phosphorus” or bioluminescence. These dinoflagellates produce a blue-ish light when disturbed. Many see this when walking the beach at night. Their footprints glow for a few seconds. At night, boaters can see this as their prop wash turns the dinoflagellates in the water column. The bioluminescence is more pronounced in the warm summer months and is believed to be defense against predation. The light is referred to as “cool” light in that the majority of the energy is used in producing light, not lost as heat as with typical incandescent bulbs – hence the birth of the LED light industry.
The dinoflagellate Karenia brevis.
Photo: Smithsonian Marine Station-Ft. Pierce FL
Several dinoflagellates produce toxins as a defense. Some generate what we call red tides. In the Gulf of Mexico, Karenia brevis is the species most responsible for red tide. Red tides typical form offshore and are blown into coastal areas via wind and currents. They are common off the coast of southwest Florida but occur occasionally in the panhandle. Many local red tides are actually formed in southwest Florida and pushed northward via currents. Red tides are known to kill marine mammals and fish, as well as closing areas for shellfish harvesting.
Like true plants, phytoplankton conduct photosynthesis. Between the diatoms and dinoflagellates, 50% of the planet’s oxygen is produced. These are truly important players in the ecology of both the open Gulf and local bays.
References
Annett, A.L., D.S. Carson, X. Crosta, A. Clarke, R.S. Ganeshram. 2010. Seasonal Progression of Diatom
Assemblages in Surface Waters of Ryder Bay, Antarctica. Polar Biology vol 33. Pp. 13-29.
Hasle, G.R., E.E. Syvertsen. 1997. Identifying Marine Phytoplankton. Academic Press Harcourt Brace and
Company. San Diego CA. edited by C.R. Tomas. Pp. 858.
Steidinger, K.A., K. Tangen. 1997. Identifying Marine Phytoplankton. Academic Press Harcourt Brace and
Company. San Diego CA. edited by C.R. Tomas. Pp. 858.
by Carrie Stevenson | Nov 3, 2017
Red mangrove growing among black needlerush in Perdido Key. Photo credit: Carrie Stevenson, UF IFAS Extension
Discovering something new is possibly the most exciting thing a field biologist can do. As students, budding biologists imagine coming across something no one else has ever noticed before, maybe even getting the opportunity to name a new bird, fish, or plant after themselves.
Well, here in Pensacola, we are discovering something that, while already named and common in other places, is extraordinarily rare for us. What we have found are red mangroves. Mangroves are small to medium-sized trees that grow in brackish coastal marshes. There are three common kinds of mangroves, black (Avicennia germinans), white (Laguncularia racemosa), and red (Rhizophora mangle).
Black mangroves are typically the northernmost dwelling species, as they can tolerate occasional freezes. They have maintained a large population in south Louisiana’s Chandeleur Islands for many years. White and red mangroves, however, typically thrive in climates that are warmer year-round—think of a latitude near Cedar Key and south. The unique prop roots of a red mangrove (often called a “walking tree”) jut out of the water, forming a thick mat of difficult-to-walk-through habitat for coastal fish, birds, and mammals. In tropical and semi-tropical locations, they form a highly productive ecosystem for estuarine fish and invertebrates, including sea urchins, oysters, mangrove and mud crabs, snapper, snook, and shrimp.
Interestingly, botanists and ecologists have been observing an expansion in range for all mangroves in the past few years. A study published 3 years ago (Cavanaugh, 2014) documented mangroves moving north along a stretch of coastline near St. Augustine. There, the mangrove population doubled between 1984-2011. The working theory behind this expansion (observed worldwide) is not necessarily warming average temperatures, but fewer hard freezes in the winter. The handful of red mangroves we have identified in the Perdido Key area have been living among the needlerush and cordgrass-dominated salt marsh quite happily for at least a full year.
Key deer thrive in mangrove forests in south Florida. Photo credit: Carrie Stevenson, UF IFAS Extension
Two researchers from Dauphin Island Sea Lab are planning to expand a study published in 2014 to determine the extent of mangrove expansion in the northern Gulf Coast. After observing black mangroves growing on barrier islands in Mississippi and Alabama, we are working with them to start a citizen science initiative that may help locate more mangroves in the Florida panhandle.
So what does all of this mean? Are mangroves taking over our salt marshes? Where did they come from? Are they going to outcompete our salt marshes by shading them out, as they have elsewhere? Will this change the food web within the marshes? Will we start getting roseate spoonbills and frigate birds nesting in north Florida? Is this a fluke due to a single warm winter, and they will die off when we get a freeze below 25° F in January? These are the questions we, and our fellow ecologists, will be asking and researching. What we do know is that red mangrove propagules (seed pods) have been floating up to north Florida for many years, but never had the right conditions to take root and thrive. Mangroves are native, beneficial plants that stabilize and protect coastlines from storms and erosion and provide valuable food and habitat for wildlife. Only time will tell if they will become commonplace in our area.
If you are curious about mangroves or interested in volunteering as an observer for the upcoming study, please contact me at ctsteven@ufl.edu. We enjoy hearing from our readers.
by Rick O'Connor | Oct 6, 2017
Back in the spring, I wrote an article about the natural history of this ancient animal. However, Florida Fish and Wildlife Conservation Commission (FWC) is interested in the status of horseshoe crabs and they need to know locations where they are breeding – and Florida Sea Grant is trying to help.
Horseshoe crabs breeding on the beach.
Photo: Florida Sea Grant
If you are not familiar with the horseshoe crab, it is a bizarre looking creature. At first glance, you might mistake it for a stingray. It has the same basic shape and a long spine for a tail. But further observation you would realize it is not a stingray at all.
So then… What is it?
When you find one, most are not comfortable with the idea of picking it up to look closer. The spine is probably dangerous and there are numerous smaller spines on the body. Actually, the long spine in the tail region is not dangerous. It is called a telson and is most often used by the animal to push through the environment when needed, as well as righting itself when upside down. It is on a ball-and-socket joint and if you pick them up, they will swing it around – albeit slowly – but it is of no danger. Note though, do not pick them up by the telson – this can damage them.
If you do try to pick them up with your hands on their sides, you will find they are well armored and have numerous clawed legs on the bottom side. At first, you are thinking it is a crab, and the claws are going to pinch, but again we would be mistaken. The claws are quite harmless – they even tickle when handled. I have held them to allow kids to place their hands in there to feel this. However, when held they will bend their abdomen between 90° and 120°, as if attempting to roll into a ball – which they cannot. At this point, they become difficult to hold. Your hands feel they are in the way and the small spines on the side of the abdomen begin to pierce your skin. So, you flip it on its back. It begins to try a 90° bend in the other direction and begins to swing the telson around. This is probably the most comfortable position for you to hold – but I am not sure what the crab thinks about it.
So, what do you have?
Well, you can see why they call it a crab. It has clawed legs and a hard shell. The body is very segmented. You can also see why it is called a “horseshoe”. But actually, it is not a crab.
Crabs are crustaceans. Crustaceans have two body segments – a head and abdomen, no middle thorax as found on insects. This is the case with the horse crab as well.
Crustaceans have 10-segmented legs, though the claw (cheliped) and swimming paddles (swimmerets) of the blue crab count as “segmented legs”. Horseshoe crabs have 10 as well – seems this IS a crab – but wait…
Crustaceans have two sets of antenna – two short ones and two long – horseshoe crabs do not have any antenna. Traditionally biologists have divided arthropods into two subphyla – those with antenna and those without – so the horseshoe crab is not a crab. It is actually more closely related to spiders, ticks, and scorpions.
Blue crabs are one of the few crabs with swimming appendages.
Photo: Molly O’Connor
It is an ancient animal, fossil horseshoe crabs in this form date back over 440 million years – out dating the dinosaurs. There are four different species of today and there probably were more species in the past. Their range extends from the tropics and temperate coastlines of the planet. Today three of the remaining four species live in Southeast Asia. The fourth, Limulus polyphemus, lives along the eastern and Gulf coast of the United States.
Unfortunately, this neat and ancient creature is becoming rare in some parts of its range. There is a commercial harvest for them. Their blood is actually blue and contains properties beneficially in medicine. Smaller ones are used as bait in the eel fishery, and there is always the classic loss of habitat. These are estuarine creatures and are often found in seagrass and muddy bottom habitats where they forage on bottom dwelling (benthic) animals.
FWC is interested in where horseshoe crabs still breed in our state. Some Sea Grant Agents in the panhandle are assisting by working with locals to report sightings. Sea Grant also has a citizen scientist tagging program to help assess their status. Horseshoe crabs typically breed in the spring and fall during the new and full moons. On those days, they are most likely to lay their eggs along the shoreline during the high tide. This month the full moon is October 5 and the new moon is October 19. We ask locals who live along the coast to search for breeding pairs on October 4-6 and October 18-20 during high tides. If you find breeding pairs, or better yet, animals along the beach laying eggs – please contact your local Sea Grant Agent. We will conduct these surveys in the spring and fall of 2018 and post best search dates at that time.
For more information on the biology of this animal read http://escambia.ifas.ufl.edu/marine/2017/04/10/our-ancient-mariner-the-horseshoe-crab/.
References
Barnes, R.D. 1980. Invertebrate Zoology. Saunders College Publishing. Philadelphia PA. pp 1089.
Florida Fish and Wildlife Conservation Commission. Facts About Horseshoe Crabs https://www.sciencedaily.com/releases/2008/02/080207135801.htm
Oldest Horseshoe Crab Fossil Found, 445 Million Years Old https://www.sciencedaily.com/releases/2008/02/080207135801.htm
by Rick O'Connor | Sep 15, 2017
I recently saw a photograph of an American Alligator (Alligator mississppiensis) crossing Perdido Key Drive on a heavy rain day. This encounter would surprise some, and unnerve many. The majority of the nuisance wildlife calls I receive are for snakes. I have never received a call for an alligator but no doubt, my colleagues in central and south Florida have. They certainly will with the landfall of Irma. Just as humans relocate for storms, wildlife does as well. High, dry ground is a need for all, and as our friends return to their homes after the storm, they will no doubt encounter creatures in the debris that can be a bit unnerving.
Alligator basking on a shoreline; photo: UF/IFAS Communications
“Nuisance” is in the eye of the beholder. Defined by the Merriam-Webster dictionary as being annoying, unpleasant, or obnoxious, a nuisance species is one we would rather not have in our yard. Snakes are one of those. Most of the people who call about snakes wish them no harm; they just do not want them on their porch or in their pool. Venomous snakes in particular raise anxiety levels, especially when children or pets are around. Though we do not get many calls on alligators, the feeling a homeowner would have if they found one in their driveway would be the same.
There were no calls on the alligator on Perdido Key. Actually, not everyone believed the photo to be legit. I cannot verify it, but I did receive a call earlier this summer when an American alligator was found swimming and basking on a Gulf beach in Navarre and later near Ft. Pickens. Though not as common as they are in central and south Florida, alligators do live here and they are found on our barrier islands. Though encounters with them are rare, how should a homeowner deal with this potential nuisance? When I give a program on snakes I typically go over four points. Let us go over the same with the alligators.
Is it venomous or not?
Obviously, this is not a question here – no crocodilian is venomous. They do have bacteria in their mouths that have caused problems for some who have survived an attack, but there is no venom. However, in south Florida identification is still important because there is more than one crocodilian roaming the landscape. The American Crocodile (Crocodylus acutus) is a native species found in coastal waters of south Florida, the northern reach of its range. The Speckled Caiman (Caiman crocodylus) is an exotic species from Central and South America that is now found in freshwater canals and lakes of southeastern Florida. It is likely that post Irma cleanup will include encounters with these two. However, this is not likely for the panhandle – our winters are too cold.
How do I avoid encounters?
Generally encounters with nuisance wildlife occur for one of two reasons; (a) we have moved into their habitat or (b), they have come to us.
With the population of Florida growing at an ever increasing rate, currently 21 million people and a growth rate of 1.77%, development continues to expand into habitat where these animals have remained out of our sight for some time. As we continue to move into these habitats, encounters with nuisance wildlife will increase. They will be forced to visit our yards and pools. It is no different with bears.
In other cases we, either knowing or unknowingly, provide food and shelter for them. Predators tend to select the easiest prey to kill, the ones that take the less energy. Human development tends to provide habitat for vermin, such as rats, in concentrated areas. This makes hunting for predators, such as snakes, bears, and alligators, much easier – and they will take advantage of this.
With alligators, (a) is more problematic than (b). Alligators have a natural fear of humans and do not typically seek us out looking for easy prey. They seem to prefer to live and hunt away from us. However, feeding alligators changes this and thus, it is a felony to do so in our state. In 2015, the state legislature developed a tiered penalty system for assessing fines and charges. As we continue to develop in areas where alligators live, it will be harder to avoid encountering them.
What do I do if I encounter one?
The general nature of wildlife is reacting to predators, prey, reproduction, and shelter. Alligators are top predators and feed on a variety of species. They are opportunistic hunters, selecting prey they can easily swallow and are relatively easy to catch. Much of these are smaller animals. If the opportunity to make a large kill presents itself, they will – however, they will drown the creature and leave it underwater to soften the carcass so they can swallow.
The method of capture usually involves lying still and waiting for prey to move within range. If encountering an alligator the questions that come to mind are: (1) am I within range? (2) are we near water? – remember they need to submerged large prey. Keep in mind that small children and pets are easier prey and care should taken when in alligator habitat.
Resources provide the following suggestions if an encounter occurs:
- They have a nature fear of humans and will try to retreat. This is true. Provide an avenue of escape for the animal. Do your best not to corner it. Remember it may react to pets and children as prey and could approach.
- If they hiss, they are warning you that you are getting too close and they are feeling threatened. Back away slowly. Sudden movements could be misinterpreted and they may defend themselves by attacking.
- Keep in mind they are fast moving for several yards, so do not think of them as slow and lethargic.
- Females guarding a nest may attack. They will charge to drive you off but typically return to the nest once you have moved to a safe distance (safe in their minds). Alligators build nests of leaf litter above ground in quiet water areas within their range. You may encounter one while hiking along shore. Avoid these nesting areas.
Alligator basking on the Escambia River; photo: Molly O’Connnor
And what if I’m bitten?
This question makes sense if you are talking snakes. With snakes, you are bitten and the snake withdraws. So the question comes up, now what? Not so much with alligators. Though alligators tend to feed on smaller and softer prey, as they increase in age and size, their skull structure adjust to where they can crush turtle shells and mammal bones. Forces have been recorded between 12 and 9452 Newtons, depending on age. When they bite they do not typically withdraw, but rather will drag you into water. Do whatever you can to avoid being dragged into water. Since 1948 there have been 388 alligator attacks, 24 were fatal. That averages to 6 attacks/year statewide and about 1 fatality every 4 years – so it is not very common. But remember, human development is encroaching and we will need to learn to live with them as our ancestors did when the animals were more numerous.
In Florida, an alligator is not considered a nuisance unless it is at least 4 feet in length. If you feel there is a nuisance alligator in your neighborhood you can call.
1-866-FWC-GATOR
References
American Crocodile: Species Profile. National Park Service. https://www.nps.gov/ever/learn/nature/crocodile.htm.
Caiman. 2017. Florida Fish and Wildlife Conservation Commission. http://www.myfwc.com/wildlifehabitats/managed/american-crocodile/caiman/.
Erickson, G.M., A.K. Lappin., A.K. Vilet. 2003. The Ontogeny of Bite-Force Performance in American Alligator (Alligator mississippiensis). Journal of Zoology. Vol 260 (3). Pp. 317-327. https://www.cambridge.org/core/journals/journal-of-zoology/article/the-ontogeny-of-bite-force-performance-in-american-alligator-alligator-mississippiensis/150E92D79C5FAEB821DDBF563888E773. P
Florida Population 2017: Demographics, Maps, and Graphs. 2017. World Population Review. http://worldpopulationreview.com/states/florida-population/.
Merriam-Webster Online Dictionary. https://www.merriam-webster.com/dictionary/nuisance.
Statewide Nuisance Alligator Program. 2017. Florida Fish and Wildlife Conservation Commission. http://myfwc.com/wildlifehabitats/managed/alligator/nuisance/.
Swiman, E., M. Hostetler, S. Webb Miller, M. Main. 2017. Living with Alligators: A Florida Reality. University of Florida Institute of Food and Agricultural Science Extension Electronic Data Information Source (EDIS) publication WEC203.
http://edis.ifas.ufl.edu/pdffiles/UW/UW23000.pdf.
Texas Parks and Wildlife. If You See An Alligator. https://tpwd.texas.gov/huntwild/wild/species/alligator/safety/index.phtml.
Wildlife Feeding Rules and Penalties. 2017. Florida Fish and Wildlife Conservation Commission. http://myfwc.com/news/resources/fact-sheets/feeding-rules-and-penalties/.
by Rick O'Connor | Aug 11, 2017
Our first POL program will happen this week – August 17 – at the Navarre Beach snorkel reef, and is sold out! We are glad you all are interested in these programs.
Well! We have another one for you. The Natural Resource Extension Agents from UF IFAS Extension will be holding a two-day water school at St. Joseph Bay. Participants will learn all about the coastal ecosystems surrounding St. Joe Bay in the classroom, snorkeling, and kayaking. Kayaks and overnight accommodations are available for those interested. This water school will be September 19-20. For more information contact Extension Agent Ray Bodrey in Gulf County or Erik Lovestrand in Franklin. Information and registration can be found at https://stjosephbay-waterschool.eventbrite.com.
by Rick O'Connor | Aug 11, 2017
the “cottonmouth” gape of this venomous snakes is a warning. Notice the banded coloration of this individual.
Photo: UF IFAS Wildlife
Also known as the Water Moccasin, this is a snake that is all too familiar with most Floridians… Or is it? Several non-venomous water snakes are often confused with the cottonmouth and are thus killed. That said, cottonmouths are common in the state near areas of water and many residents do have encounters with them. This fact sheet will provide information that help reduce negative encounters with this venomous snake.
DESCRIPTION
- cottonmouths have a relatively thick-stout body with a broad head and thin neck
- they are generally banded and can be brown, gray, reddish in color; many become darker with age and may be solid black; cottonmouths who frequent tannic waters may have cooper color to them
- average length 36″ (3 ft.); max length 74″ (6 ft.)
JUVENILE DESCRIPTION
- copper colored with a yellowish-green tipped tail; used to attract prey
HOW TO TELL FROM NON-VENOMOUS WATER SNAKES
- there are several species of water snakes from the genus Neroidia which are confused with cottonmouths
- the scales between the eyes on top of the head are larger than others on the head; they have narrow necks
- Neroidia will have heads shaped more like your thumb and neck is as wide as head – NOTE: Neroidia CAN WIDEN THEIR HEAD WHEN THREATENED
- when head is viewed from above, the eyes of the cottonmouth are hard to see
- cottonmouths have a creamed colored cheek with dark “mask” extending from eye to back of lower jaw
- Neroidia may have creamed colored cheek but will lack “mask”; will possess thin vertical stripes that extend from lower to upper jaw
- there are single scales extending from the vent (anus) to tip of tail in cottonmouths; those same scales are divided into multiple ones on Neroidia
- the underside of the cottonmouth tail is usually dark; Neroidia is usually lighter in color
- pupil of cottonmouth is elliptical; it is round on Neroidia
- cottonmouths, being members of the pit viper family, will have heat sensing pit between nostril and eye; Neroidia will lack this pit
- scales are keeled, but this is true for some non-venomous snakes
This banded water snake is often confused with the cottonmouth. This animal has the vertical stripes extending from the lower jaw, which is lacking in the cottonmouth.
Photo: University of Georgia
HOW TO TELL FROM OTHER PIT VIPERS
- cottonmouths are often confused with copperheads – both in same genus
- copperheads will lack characteristic “mask” found on cottonmouths and rattlesnakes
- the bands of the copperhead are more uniformed than the cottonmouth and are shaped like an hour glass
- copperheads are generally lighter in color
- it is difficult to tell young copperheads and cottonmouths apart; both have the light yellow-green tipped tail and light body coloring
SUBSPECIES OF COTTONMOUTHS
- there three recognized subspecies of cottonmouths
- the Florida Cottonmouth (Florida (A.p.conanti) – is darker, many times black, with two vertical bars on snout; found throughout the state of Florida
- the Eastern Cottonmouth (A. p. piscivorous) is lighter in color than the Florida and has no pattern on snout; found in extreme western Florida panhandle and the Appalachian valley of Alabama, Georgia, Tennessee, and North Carolina
- the Western Cottonmouth (A.p.leucostoma) – is similar to the eastern cottonmouth but darker in color; found in Mississippi, Louisiana, Texas, and Oklahoma
WHATS IN A NAME
- The Cottonmouth and the Water Moccasin are the two names for the same snake; herpetologist prefer to use the name Cottonmouth
- The snake was originally described by B.G.E. Lace (1789) using the term “piscivorous”; which means “fish eater”
- Gerard Troost (1836) describe the western subspecies using the term “leucostoma”; which means “white mouth”
- Howard Kay Gloyd (1969) described the Florida subspecies using the term “conanti”; which was honoring the herpetologist Roger Conant of the Philadelphia Zoo
Many in the panhandle use the terms cottonmouth and copperhead interchangeably. They are closely related but this photo of a copperhead shows the lighter coloration and the hour-glass shaped pattern of the blotches along the body.
Photo: UF IFAS Wildlife
BEHAVIOR
- cottonmouths are found throughout the southeast United States but avoid mountainous areas
- they are usually found with 30 feet of a water source, though some have been found as far as 100 feet away
- they prefer slow, quiet, backwater areas over faster flowing waterways
- they are most common in pine flatwoods but can be found in a variety of habitats and do well near humans
- they have been found in brackish water areas but freshwater is usually nearby
- they are becoming more common on barrier islands, and in some cases in high numbers, but do need sources of freshwater; they cannot extract from seawater
- cottonmouths hunt primarily at night; though daylight hunting happens
- on cool mornings they may climb lower branches of trees to bask; usually close to water
- they will remain still in one location for long periods of time waiting for prey to come within range; but they are known to stalk prey as well
- when prey are found they will strike using their hollow fangs to inject a hemotoxin; this venom is known to contain components that cause death, by attacking the muscle and circulatory system, and digestive enzymes to begin the process before swallowing
- in the cooler parts of their range cottonmouths will hibernate; but tend to be active year round in FL
PREY
- cottonmouths are carnivorous and opportunistic; prey include fish, small mammals, reptiles and birds; they will feed on smaller cottonmouths
- they are known to scavenge and are attracted to the smell of dead fish
- they hunt primarily at night but are known to during daylight hours as well
- they hunt fish and CAN bite underwater – despite the legend that they cannot
Cottonmouth’s are known to feed on a variety of prey including carrion.
Photo: University of Florida
PREDATORS
- primary predator include alligators, kingsnakes, and larger cottonmouths
- secondary predators include large mammals, birds, hawks, and owls
- cottonmouths tend to “freeze” when they first detect a predator – no movement at all
- if the predator gets too close they will vibrate their tail in leaf litter to alert the intruder and may gape their mouth showing the white inside of their “cottonmouth”; they may also flatten their bodies to appear bigger and release a musk as a warning
- they prefer to flee than bite but they will strike if they have nowhere to flee
REPRODUCTION
- mating occurs in spring and sometimes fall; in Florida they may mate year round
- males sense pheromones from females to know when it is time and, like other vipers, males may fight for the right to mate
- females can store sperm for long periods of time and typically breed every other year
- females give live birth in late summer to early fall; they sometimes congregate to give birth
- the average number of offspring/litter is 7-12 but can be as high as 22
Is this a cottonmouth?
No, it is not…
Can you tell why?
Photo: University of Florida
DEALING WITH ENCOUNTERS
KEEPING THEM AT A DISTANCE
- when hiking in cottonmouth territory it is recommended to wear high boots and look down while walking; if you need to look ahead we recommend you stop walking – look ahead – and then put your eyes back to the ground while walking
- stay on trails; snakes do not like short grass; avoid walking in tall grass where they may be hiding
- to keep cottonmouths away from your home – reduce food sources, freshwater sources, and shelter areas
- cottonmouths like fish ponds and are often found in the filter system; they may be attracted to swimming pools
- cottonmouths also eat rodents; bird feeders, sacks of corn, wood and brush pikes can attract cottonmouth prey, and thus cottonmouths
- if you must have brush piles and bird feeders place them away areas where people frequent – away from front and back doors, sidewalks, etc.
- many properties have natural ponds and swimming pools; if encounters are a problem consider placing some small mesh fencing to keep them from reaching the source may be helpful; this fencing should be buried 2-6″ below the surface and the wooden stakes should be on your side of the fence – snakes can climb the rough wood stakes; if you cannot continue the fencing across your entire property – make a 90° turn AWAY from your property to encourage them to return from where they came
IF I ENCOUNTER ONE
- despite stories, cottonmouths do not chase people; most will sit very still hoping you do not see them; I have personally accidentally placed my foot within inches of a cottonmouths with no reaction from the snakes; their first reaction is to “freeze”
- if they feel you are getting too close they often will begin to vibrate their tail very fast; this means they are getting nervous and are warning you to stay clear; many times they are in leaf litter when they do this and you can hear them – DO NOT APPROACH ANY CLOSER; the probability of a strike is still low, but has increased
- another warning behavior is mouth gaping and showing of white mouth- “cottonmouth”; though strike probability is still low, studies show that gaping cottonmouths tend to strike more often than tail vibrating ones – DO NOT APPROACH; move back and allow the snake to pass
The dark phase of the cottonmouth. This is an older individual.
Photo: UF IFAS
BUT WHAT IF I ALLOW IT TO PASS AND IT IS HEADING FURTHER ON TO MY PROPERTY?
- great news right?
- statistics show that about 95% of people bitten by snakes are trying to catch it or kill it – so trying to remove it yourself significantly increases your chance of getting bit
- many have had success with sweeping non-venomous snakes into a trash can with a broom and releasing somewhere… But these are non-venomous snakes, we recommend professionals for venomous snake removal
- you may have no other optional than to kill the snake; if this is the case be careful… Again, many are bitten trying to kill snakes; also know that snakes are known to strike after they are a dead
WHAT IF I AM BITTEN?
- first know that death from cottonmouths is very rare; annually in the U.S. about 7,000 – 8,000 people are bitten by venomous snakes (about 1 in 40,000 people) and about 5-6 die (about 1 in 50 million)
- also know that many times vipers give what is called a “dry bite” – no venom injected; but you do not know this so treat as if venom was injected; MANY WHO DIE FROM VENOMOUS SNAKE BITES DID NOT SEEK MEDICAL ATTENTION
- first rule is DO NOT GET BIT TWICE; after being bit many people will then try to kill the snake and are bitten again; many feel that they need the snake at the hospital for identification – they do not
- second rule is to remain calm; easier said than done, but an elevated heart rate will move the toxin within the blood faster
- with toxic viper bites there will be pain and swelling; remove watches, jewelry, or any tight fitting clothing from bite area
- you do not need to add ice or heat
- we do not recommend tourniquets, lancing the bite and sucking out venom; many times the venom has spread from the bite area and health officials have found that many times there are more problems with the “first aid” than with the bite itself
- try not to move the limb where bite occurred- easier said than done; if you can elevate your heart above the bite this is good
- do not drink alcohol; you may think you need a drink right now but you do not; alcohol or caffeine can accelerate heart and spread venom faster
- call 911 and alert the closest hospital that you have a snake bite victim coming in; answer any questions they may have to the best of your ability
- again, do your best to relax and get to a hospital; fatalities are rare due to the excellent medical care in this country
All of this said, there is a lot of concern surrounding cottonmouths in Florida. As we expand our neighborhoods into more of their habitat, we will encounter more of them. In some cases, the location for their resources may be our neighborhoods. We will need to learn how to identify them and understand their behavior to avoid negative encounters. The statistics show that they are not as big a threat as they are perceived to be, but folks are still concerned for their family and pets – and understandably so. Hopefully information in this fact sheet will be of help to you.
REFERENCES
Ashton, R.E., P.S. Ashton. 1981. Handbook of Reptiles and Amphibians of Florida; Part I Snakes. Windward Publishing. Miami FL. pp. 175.
Gibbons, W., M. Dorcas. 2005. Snakes of the Southeast. University of Georgia Press. Athens, GA. Pp. 253.
Gibbons, W. 2017. Snakes of the Eastern U.S. University of Georgia. Athens GA. pp. 416.
http://www.bioone.org/doi/abs/10.2994/1808-9798(2008)3%5B175:TEOICS%5D2.0.CO%3B2
http://www.bioone.org/doi/abs/10.1643/CH-04-243R1?journalCode=cope
https://academic.oup.com/bioscience/article/58/10/947/245888/Pitviper-Scavenging-at-the-Intertidal-Zone-An
http://escholarship.org/uc/item/9j69w675
http://ufdc.ufl.edu/files/UFE0046057/00001/WIXSON_J.pdf
http://www.herpconbio.org/Volume_10/Issue_2/Hanson_McElroy_2015.pdf
http://onlinelibrary.wiley.com/doi/10.1111/j.1365-2699.2008.02075.x/full
http://www.bioone.org/doi/abs/10.1643/0045-8511(2002)002%5B0195:DBOCAP%5D2.0.CO%3B2
https://academic.oup.com/beheco/article/15/2/365/223992/Size-based-variation-in-antipredator-behavior
http://www.jstor.org/stable/3890390?seq=1#page_scan_tab_contents
https://www.floridamuseum.ufl.edu/herpetology/fl-snakes/list/agkistrodon-piscivorus-piscivorus/
http://ufwildlife.ifas.ufl.edu/pdfs/cottonmouth.pdf
Johnson, S.A. Frequently Asked Questions About Venomous Snakes. http://ufwildlife.ifas.ufl.edu/venomous_snake_faqs.shtml.
