by Carrie Stevenson | May 22, 2020
Sea pork comes in a wide variety of shapes and sizes. Photo credit: Carrie Stevenson, UF IFAS Extension
Recently I was walking the beach, enjoying a sunset and looking around at the shells and other oddities in the wrack line where waves deposit their floating treasures. Something bright green and oblong caught my eye. It was emerald in color, smooth yet fuzzy at the same time, and firm to the touch. At first, I thought it was a sea bean–a collective term for the many species of seeds and fruits that float to our shores from tropical locations in the Caribbean or Central/South America. The bright green definitely seemed like something botanical in nature. However, the vast majority of sea beans have a woody, protective shell similar to our more familiar pecans or acorns.
I remembered a family member asking about finding a mystery chunk of pink mass she found on the beach a few years ago. It resembled a pork chop more than anything else.
A different variety of sea pork that really lives up to its name. Photo credit: Stephanie Stevenson, Duval County Master Gardener
Looking closer and consulting a couple of resources, I realized we had both (most likely!) happened upon one of the oddest and often-questioned finds on our beaches: sea pork. Ranging in color from beige and pale pink to red or green, sea pork is a tunicate (or sea squirt), a member of the Phylum Chordata, home to all the vertebrate and semi-vertebrate animals. While they look and feel more like a cross between invertebrate slugs or sponges, the tunicates are more advanced organisms, possessing a primitive backbone in their larval “tadpole” form. Despite their blob-like appearance, they are more closely related to vertebrate animals than they are to corals or sponges.
The unusual life cycle of the tunicate. Photo credit: University of Washington, used with permission with Florida Master Naturalist program
During their short (just hours-long) larval stage, the tunicate larvae uses its nerve cord (supported by a notochord similar to a vertebrate spine) to communicate with a cerebral vesicle, which works like a brain. Similar to fish, this primitive brain uses an otolith to orient itself in the water, and an eyespot to detect light. These brain-like tools are utilized to locate an appropriate location to settle permanently. Using a sticky substance, the tunicate will attach its head directly to a hard surface (rocks, boats, docks, etc.) and go through a metamorphosis of sorts. The tunicate reabsorbs its tail and starts forming the shape and structure it needs for adulthood.
As an adult, the organism has a barrel shape covered by a tough tunic-like skin (hence “tunicate”). Adult bodies have two siphons, one to bring water in, another to shoot it out (giving them their other nickname, the sea squirt). The water passes through an atrium with organs that allow it to filter feed, trapping plankton and oxygen. The tunicates will spend most of their lives attached to a surface, pumping water in and out as filter feeders. They may be solitary or live in colonies, and vary widely in color and shape, lending variety to those chunks of sea pork found washing up.
I am still awaiting positive identification from an expert on my green find to confirm that it is, indeed, a tunicate and not an unfamiliar plant. Consulting with Extension colleagues, for now we are pretty confidently going with green sea pork. If you have seen one of these before or something resembling sea pork, let us know! It is fascinating to see the variety and unusual shapes and colors.
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by Rick O'Connor | May 17, 2020
In my time educating the public about Florida turtles I have found that most Floridians have not heard of diamondback terrapins. They have heard of, and seen turtles, but are not sure what the names of the different species are and are not familiar with the term terrapin at all. Which brings up the question – what is the different between a turtle, a tortoise, and a terrapin?
The light colored skin and dark markings are pretty unique to the terrapin.
Photo: Molly O’Connor
Honestly, they are cultural terms and not “biological” descriptions. We associate the term “tortoise” with a land turtle – and this is true – yet we call the box turtle a “turtle” – which is fine. In Great Britain they call almost everything a “terrapin”. The term “terrapin” is a Delaware Indian term meaning “edible turtle”. Most turtles are edible, but this term stuck to a group of brackish water turtles in the Chesapeake area near Delaware we now call “terrapins”.
In the Mid-Atlantic states, terrapins are more known than they are here – and they appear to be more abundant. They are the mascot of the University of Maryland, and the official state reptile there. “Turtle Soup”, a popular cultural dish in the Chesapeake, is made with terrapins. It was served as part of the state dinner when Abraham Lincoln was president – considering it a classic “American” dish. They were harvested by walking through the marshes with a burlap sack and a gig. A sack could bring a harvester about $10, but when the popularity of the dish increased, hand harvesting could not keep up with demand and terrapin farms began. I know there were terrapin farms in the Carolinas, but there was one near Mobile, Alabama as well. Apparently, terrapins existed outside of the Chesapeake – and that brings us back to Florida… we have them too!
Ornate Diamondback Terrapins Depend on Coastal Marshes and Sea Grass Habitats
There are seven subspecies of this brackish water turtle. They range from Massachusetts to Texas. It is the only resident brackish water species, spending its whole life in salt marshes (or mangroves in south Florida). Florida has five of the seven subspecies, and three of the seven ONLY live in Florida – yet most of us do not know the animal exist.
Very few researchers worked with terrapins in this state – there was virtually nothing known about them in panhandle. In 2005 I began to survey panhandle marshes to see if terrapins existed here. I grew up in the panhandle, and like so many others, had never seen or heard of one. I asked local fishermen who use to gillnet the marshes back in the 1950s and 1960s (when it was allowed) if they were aware of this this turtle. I asked them “did you ever capture a terrapin?” They did not know what I was talking about. And then I showed them a picture… “OH… yea, we did catch these once in a while – what are they called again? Terrapins?”. This was a game changer for me in terrapin education – show them a terrapin and ask if they have ever seen a turtle that looks like this.
The response was still “what is that? It’s beautiful!”… and they are. Terrapins have light colored skin with dark specks or bars – a really pretty cool looking turtle. Oh, and they are in the panhandle, just not in big numbers – or, at least, we have not found them in big numbers 😊.
These brackish water turtles spend their entire lives in a marsh system feeding on mollusk and crustaceans. Like map turtles (their nearest cousins), the females are larger with wide heads for crushing the shells of their prey. They are considered an important member of the ecosystem in that the reduction of terrapins can cause an increase in the marsh periwinkle (a popular snail food) who would in turn stop feeding on leaf litter and attack the live plants themselves – threatening the existence of the marsh. So, they are important predators on marsh grazers. Not having a lot of trees in a salt marsh, you do not see them basking on logs as you do with other riverine turtles. They do, however, exit the water and bury in the mud/sand for long periods to bask.
A baby terrapin.
Photo: Molly O’Connor
After mating, the females usually leave the marsh for the open estuary, swim along the shorelines looking for high/dry ground for nesting. More often than not, these are sandy beaches – but they have been known to dig nest in crushed shell mounds, dredge spoil islands, along highways, backyards, and even runways of airports – wherever “high and dry” can be found in a marsh. In Louisiana a lady found one roaming around inside her outdoor shower – good luck nesting there!
The females lay about 10 eggs in a clutch and will lay more than one clutch each year. Baby terrapins are one of the coolest looking turtles you will see. They emerge from the nest in late summer and fall, hiding in the wrack debris along the shoreline. It is believed they actually have a more terrestrial life early on before entering the water and living out their lives in the marsh.
The popularity of turtle soup has waned since the Civil War, as have the wild harvest and aquaculture projects. However, the turtle is still under tremendous pressure from humans. We began using wired crab traps in the 1950s and terrapins have a habit of swimming into these, where they drown. The problem is not that large in Florida, but in the Chesapeake, they have found as many as 40 terrapins in one crab trap! Most of these are “ghost crab traps” – ones that “got away” from the owner but are still harvesting marine live – including crabs. One paper indicated that in the early part of the 21st century, in one year in the Chesapeake, over 900,000 blue crabs died in ghost crab traps – a commercial value of about $300,000. So, the ghost crab trap is a problem whether it kills terrapins, redfish, flounder, or blue crab. Today, many crab traps have biodegradable panels so that if the trap “gets away” it will eventually breakdown and not capture organisms like terrapins. In the Chesapeake many states require crab traps to have a By-Catch Reduction Device (BRD) to keep terrapins out – but allow crabs in. They are not required in Florida, however FWC will provide them for free if you are interested. I have some in my office in Pensacola and more than willing to give them to you. FWC also hosts crab trap removal programs, and I encourage you to participate in these.
This orange plastic rectangle is a Bycatch Reduction Device (BRD) used to keep terrapins out of crab traps – but not crabs.
Photo: Rick O’Connor
A bigger issue for Florida is the land-based predators. As we moved closer and closer to the salt marshes, we built bridges and roads that allowed land-based predators to reach the nesting beaches they previously did not have access to. Raccoons in particular are a big problem, depredating as many as 90% of the terrapin nests. Poaching for the pet trade is rising and FWC is working on this. Several major arrests have been made in Florida in recent years. It is illegal to sell Florida turtles, so do not buy them if you see them being sold somewhere. Report the activity to FWC.
Due to all of this, terrapins afford some form of protection in each of the coastal states where they exist. Some list them as “endangered” or “threatened”. In Florida, they do not have this label, but they are protected by FWC. No one is allowed to have more than two in their possession, and you are not allowed to have any eggs.
It is an amazing turtle. I currently conduct a citizen science program monitoring them in the western panhandle. I have a lot of eager volunteers wanting to see their first one in the wild. I hope they do soon. I hope they hang around long enough for everyone to see one in the wild.
by Rick O'Connor | May 14, 2020
As we embrace the marine life of the Gulf of Mexico during this year of “Embracing the Gulf”, we are currently hooked on worms. In the last article we talked about the gross and creepy flatworms. Gross because they are flat, pale in color, only have a mouth so they have to go to the bathroom using it – and creepy in that many of them are parasites, living in the bodies over vertebrates (particularly fish) and that is just creepy. You may ask why would we even “embrace” such a thing? Well… because they do exist and most of us know nothing about them.
A nemertean worm.
Photo: Okinawa Institute of Science
This week we continue with worms. We continue with a different kind of flatworm. They are not as gross, but maybe a little creepy. They are called nemertean worms and I am pretty sure (a) you have never heard of them, and (b) you have never seen one. So why “embrace” these? Well… again it is education. They do exist, and one day you MAY see one – and know what you are looking at.
Nemerteans are flatworms. They are usually pale in color but a different from the classis fluke or tapeworm in a couple of ways.
1) They do have a way for food to enter and another for waste to leave, what we call a complete digestive tract – and that’s nice.
2) They have this long extension connected to their head called a proboscis. Many of them have a dart at the end they can use to kill their prey – and that’s creepy.
3) And as mentioned, most are carnivores, feeding on small invertebrates – and that’s okay.
We rarely see them because they are nocturnal – hiding under rocks, shells, seaweed during the day and hunting at night. Most are about eight inches long but some in the Pacific reach almost eight feet!
I would put that in the creepy file.
As we said, they are usually pale in color, though some may have yellow, orange, red, or even green hues to them. Their heads are spade shaped and, again, hold a retracted proboscis. This proboscis can be over half the length of the worm. At the end is a stylet (a dart) which they can use to stab their prey (small invertebrates). They can stab repeatedly, like using a knife, – they may stab and grab, like using a claw – or they may be a species that has toxin and kills their prey that way.
Nice.
Some would add this to the creepy file as well. A long pale worm, moving at night, extending a long proboscis when they get near you with a sharp dart at the end they essentially “sting” you like a bee.
Yea, creepy.
But we NEVER hear about such things with humans. They hunt small invertebrates like amphipods, isopods, and things like that. If you picked one up, would it stick the dart in you? My hunch would be yes – I honestly don’t know, I have only seen one to two in the 35+ years I have been teaching marine science and I did not pick them up. I have never met anyone who has and have never read “DON’T PICK THESE UP – VERY DANGERSOUS”. So, my hunch is that it would not be very painful at all.
But don’t take my word for it – again, I have rarely seen one… so, don’t pick them up 😊
There are about 650 species of nemertean worms in the world, 22 live in the Gulf of Mexico, and 16 live in the northern Gulf (near us). They are basically marine, move across the environment on their slime trails, seeking prey primarily by the sense of smell at night. Unlike the flukes and tapeworms, there are male and females in this group. They fertilize their eggs externally to make the next generation of these harpooning hunters of the Gulf.
I don’t know if you will ever come across one of these. You will know it by the flat body, pale color, and spade-shaped head, but I think it would be pretty neat to find one. There are more worms to learn about in the Gulf of Mexico, but we will do that in another edition.
by Carrie Stevenson | May 8, 2020
In ecology, a “keystone” species is as crucial to an ecosystem as the central stone in this arch.
In architecture, a “keystone” is the top, central block in an arch structure, the one that holds the entire building up. Without it, the bricks around it collapse. With it, there is nothing stronger.
So, when you hear an animal referred to as a “keystone” species, it should get your attention—especially when that species is listed as threatened by state and federal wildlife agencies. In northwest Florida, one of the species upon which the entire longleaf ecosystem is built is the humble gopher tortoise (Gopherus polyphemus).
Gopher tortoises are long-lived, protected by their thick shells and deep burrows. Photo credit: Carrie Stevenson, UF IFAS Extension
Once hunted for food and currently in competition with humans for buildable land, this long-lived reptile is an architect in its own right. The tortoises are called “gophers” because of their tunnel building and burrow construction expertise. The tortoises spend about 80% of their time near their burrows, of which they have multiple over their lifetimes. Being a cold-blooded reptile, the burrows allow the tortoises a place to live in the temperature-regulated soil.
The average adult gopher tortoise is about 9-11 inches long, although they can be larger. They have thick feet resembling those of an elephant, and scaly front legs used for digging and burrowing. They are tan, brown, or gray, and live in dry, sandy, upland habitats. Their propensity for dry forestland is typically why their populations are in peril, as this is also the best land for building and development.
The average gopher tortoise’s burrow is 6.5 feet deep and 15-40 feet long, and provides habitat for 350 other species! Those commensal species that share its burrow are mostly invertebrates, but at least 50 are larger backboned species like frogs, snakes, rabbits, and burrowing owls. During forest fires, there are stories of multiple species—from deer and snakes and turtles—calling a truce and hiding in the burrows together until the flames blow over.
Gopher tortoises are nesting right now–be sure to observe from a distance!
Right now—from May to July—is nesting season for gopher tortoises. They lay eggs in the soft sand of their burrow apron, which is the triangular spread of loose sand at the opening of the burrow. Eggs incubate all summer and emerge between August and November. The newly hatched tortoises can expect to live 40 to 60 years in the wild. They live on a variety of grasses and low-growing plants native to longleaf pine, oak forests, and coastal dunes, including wiregrass and gopher apple. They are adapted to routine fires, as they are safe in their burrows and the new growth after a burn provides an abundance of their grassy food sources.
by Chris Verlinde | May 1, 2020
Black Skimmers foraging for fish. Photo Credit: Jan Trzepacz, Pelican Lane Arts.
Black Skimmers and Least Terns, state listed species of seabirds, have returned along the coastal areas of the northern Gulf of Mexico! These colorful, dynamic birds are fun to watch, which can be done without disturbing the them.
Shorebirds foraging. Photo Credit: Jan Trzepacz, Pelican Lane Arts.
Black Skimmer with a fish. Photo Credit: Jan Trzepacz, Pelican Lane Arts.
What is the difference between a seabird and shorebird?
Among other behaviors, their foraging habits are the easiest way to distinguish between the two. The seabirds depend on the open water to forage on fish and small invertebrates. The shorebirds are the camouflaged birds that can found along the shore, using their specialized beaks to poke in the sandy areas to forage for invertebrates.
Both seabirds and shorebirds nest on our local beaches, spoil islands, and artificial habitats such as gravel rooftops. Many of these birds are listed as endangered or threatened species by state and federal agencies.
Juvenile Black Skimmer learning to forage. Photo Credit: Jan Trzepacz, Pelican Lane Arts.
Adult black skimmers are easily identified by their long, black and orange bills, black upper body and white underside. They are most active in the early morning and evening while feeding. You can watch them swoop and skim along the water at many locations along the Gulf Coast. Watch for their tell-tale skimming as they skim the surface of the water with their beaks open, foraging for small fish and invertebrates. The lower mandible (beak) is longer than the upper mandible, this adaptation allows these birds to be efficient at catching their prey.
Least Tern “dive bombing” a Black Skimmer that is too close to the Least Tern nest. Photo Credit: Jan Trzepacz, Pelican Lane Arts.
Adult breeding least terns are much smaller birds with a white underside and a grey-upper body. Their bill is yellow, they have a white forehead and a black stripe across their eyes. Just above the tail feathers, there are two dark primary feathers that appear to look like a black tip at the back end of the bird. Terns feed by diving down to the water to grab their prey. They also use this “dive-bombing” technique to ward off predators, pets and humans from their nests, eggs and chicks.
Least Tern with chicks. Photo Credit: Jan Trzepacz, Pelican Lane Arts.
Both Black Skimmers and Least Terns nest in colonies, which means they nest with many other birds. Black skimmers and Least Terns nest in sandy areas along the beach. They create a “scrape” in the sand. The birds lay their eggs in the shallow depression, the eggs blend into the beach sand and are very hard to see by humans and predators. In order to avoid disturbing the birds when they are sitting on their nests, known nesting areas are temporarily roped off by Audubon and/or Florida Fish and Wildlife Conservation Commission (FWC) representatives. This is done to protect the birds while they are nesting, caring for the babies and as the babies begin to learn to fly and forage for themselves.
Threats to these beautiful acrobats include loss of habitat, which means less space for the birds to rest, nest and forage. Disturbances from human caused activities such as:
- walking through nesting grounds
- allowing pets to run off-leash in nesting areas
- feral cats and other predators
- litter
- driving on the beach
- fireworks and other loud noises
Audubon and FWC rope-off nesting areas to protect the birds, their eggs and chicks. These nesting areas have signage asking visitors to stay out of nesting zones, so the chicks have a better chance of surviving. When a bird is disturbed off their nest, there is increased vulnerability to predators, heat and the parents may not return to the nest.
Black Skimmer feeding a chick. Photo Credit: Jan Trzepacz, Pelican Lane Arts.
To observe these birds, stay a safe distance away, zoom in with a telescope, phone, camera or binoculars, you may see a fluffy little chick! Let’s all work to give the birds some space.
Special thanks to Jan Trzepacz of Pelican Lane Arts for the use of these beautiful photos.
To learn about the Audubon Shorebird program on Navarre Beach, FL check out the Relax on Navarre Beach Facebook webinar presentation by Caroline Stahala, Audubon Western Florida Panhandle Shorebird Program Coordinator:
In some areas these birds nest close to the road. These areas have temporarily reduced speed limits, please drive the speed limit to avoid hitting a chick. If you are interested in receiving a “chick magnet” for your car, 
to show you support bird conservation, please send an email to: chrismv@ufl.edu, Please put “chick magnet” in the subject line. Please allow 2 weeks to receive your magnet in the mail. Limited quantities available.
by Rick O'Connor | Apr 17, 2020
I’d like to be a jellyfish… cause jellyfish don’t pay rent…
They don’t walk and they don’t talk with some Euro-trash accent…
Their just simple protoplasm… clear as cellophane
They ride the winds of fortune… life without a brain
These lyrics from Jimmy Buffett’s song Mental Floss sort of sums it up doesn’t it. The easy-going lifestyle of the jellyfish.
Everyone who visits the Gulf coast knows about these guys, but few people… very few… like them. For most, the term jellyfish signals “pain”, “fear”, and “death”. The purple flag is flying, and no one wants to enter the water. Folks from the Midwest call local hotels and condos asking, “when are the jellyfish going to be there?” It’s understandable. Who wants to spend their week vacation on the Gulf inside a hotel because you can’t go swimming?
I found this along the shore last winter. These are cannonball jellyfish.
I would almost (…almost) rather be diving with a shark than hundreds of jellyfish. When you spot them, they are everywhere. Quietly swarming like ghosts. You push them off and they appear to move towards you – almost like smoke from a campfire, you can’t get away.
They are creepy things. But amazing too!
As Mr. Buffett’s points out, they are simple “protoplasm”. Their body is primarily a jelly-like substance called mesoglea – and most of that is water. If you place a dead jellyfish on your dock and come back that afternoon, you will probably find just a “stain” of where it was – there is almost nothing to them.
The “bell” of the jellyfish is mostly mesoglea. Some jellyfish have thick layers of this, others much thinner. Some have a small flap of skin along the margins of the bell called the velum which they can undulate and swim – but they are not strong swimmers. If the tide is going out, swim as they may… their heading out also.
The bell shaped body of a jellyfish with numerous tentacles.
Many species of jellyfish have interesting markings within the bell. One has a white-colored structure that forms a 4-leaf clover. Another has red triangles all connecting at the center of the bell. For many, these structures are the ones that produce the gametes. Jellyfish reproduce sexually but are hermaphroditic – meaning they produce female eggs and male sperm in the same animal. There is no physical contact between animals, they just release the gametes into the ocean when they are in thick swarms and wah-la… new jellyfish – many new jellyfish.
On the bottom of the bell is a single opening that leads to a single pouch. This opening is the mouth, and the pouch is called the gastrovascular cavity. Jellyfish are predators – carnivores. There are no teeth, and most do not seek their prey – their prey finds them. Hanging from their bell are the tools of the killing trade, the part of this animal we do not like… the tentacles. Some tentacles can extend for several feet beyond the bell, others you can hardly notice them – but this is where the killing happens.
Along the tentacles there are small capsules called cnidoblasts which contain small cells called nematocyst. These nematocyst contain a coiled dart which at the end contains a drop of venom. There is a trigger associated with this cell. The jellyfish does not fire it – instead, the prey bumps the trigger and the nematocyst “fires”. The drop of venom is injected, along with the hundreds of other nematocysts along the tentacle the fish just bumped. This venom paralyzes the prey, other tentacles coil around it firing more nematocysts, and the tentacles retract towards the mouth – bingo… lunch.
This box jellyfish was found near NAS Pensacola in November of 2015.
Photo: Brad Peterman
Of course, the same happens when people bump into them. For us it is painful and unpleasant – but we are not consumed. That said, some species are quite painful. Some will force people to the hospital, and some have even killed people. The Box Jellyfish is the most notorious of these deadly ones. Known for their habits in Australia, there are at least two species found in the Gulf. The ones found here are not common, and there are no reported deaths, but they do exist. The Four-Handed is the one more widespread here. It actually has eyes, can detect predators and prey and swim towards or away from them, and the male fertilizes the female internally – not your typical jellyfish.
The more familiar painful one is the Portuguese Man-of-War. This creature is more like a sponge in that it is not just one creature but a large “condo” of many. Some cells are specialized in feeding, these are found on their long tentacles. Others specialize in reproduction; these are found near the blue colored air bag. They produce this blueish colored air bag which is exposed above the surface. The wind pushes on the bag like a sail and this moves the creature across the environment in search of food. Hanging from the bag are long tentacles which are made up of individuals whose stomachs are all connected. So, when one group of cells makes contact and kills a prey – they consume it and the tissue is moved through the connecting stomachs to feed the whole colony. To feed a whole colony, you need a big fish – to kill a big fish, you need a strong toxin, and they have it. These are VERY painful and have put people in the hospital, some have died. Some say that the Portuguese man-of-war is not a “true” jellyfish. This is true in the sense that they belong to a different class of jellyfish. There are three classes, the Scyphozoans being what we call the “true” jellyfish – Portuguese man-of-wars are not scyphozoans, but rather hydrozoans.
The colonial Portuguese man-of-war.
Photo: NOAA
Another interesting thing about jellyfish, is that they are all not jellyfish-like. As we just mentioned, there are two other classes and one other phylum of jellyfish-like animals. Hydrozoans and anthozoans are not your typical jellyfish. Rather than being bell-shaped and drifting in the ocean looking for food, they are attached to the seafloor and look more like flowers. Their tentacles are usually smaller but do contain nematocysts. Their toxin can be strong, some do eat fish, but most have a weaker toxin and feed on very small creatures – some only eat plankton. These would include the hydra, sea anemones, and the corals. As mentioned above, this also would include the Portuguese man-of-war.
Comb jellies are those jellies that drift in the currents and have no tentacles. We commonly collect them and toss them at each other. When I was growing up, we referred to them as “football jellies” because of this. The reason they do not sting is not because they do not have tentacles (some species do) but rather they do not have nematocyst and cannot. Rather they have special cells called colloblast that produce a drop of sticky glue at the end which they use to capture prey. Not having toxins, they cannot kill large prey but rather feed on smaller creatures like plankton and each other – they are cannibals. For this reason, they are in a whole different phylum.
The nonvenmous comb jelly.
Photo: Bryan Fluech
The jellyfish of the Gulf are a nuisance at times but are actually amazing creatures.
