by Rick O'Connor | Dec 17, 2021
This is another one of those fish in this series that is not often seen but when you do see one you will ask “what is that?” – So, we will answer the question by including it here.
Like the frogfish we have already written about, batfish are described by Hoese and Moore1 as “grotesque” and they take it a step further by telling us all “ugly” fish (as they say) are grouped into what many call “dogfish”. As with the frogfish, I am not sure I would use the term grotesque, but they are strange looking.
Juvenile Polka-Dot Batfish (Ogcocephalus radiatus) in the polluted intracoastal waterway in Palm Beach County, FL.
Photo: Science Photo Library
I have only seen a couple in my life. Hoese and Moore mention they are often brought up in shrimp trawls, and I have seen them while doing trawl surveys at Dauphin Island Sea Lab. I also found one while snorkeling along a seawall near Gulf Breeze FL. So, they are out there just not encountered as often, or as well known, or seen as frequently, as many other fish in the Gulf. Another reason to include this group here.
It is hard to describe what this fish looks like. They are, as they say, dorso-ventrally flattened – meaning from top to bottom, not side to side – like a stingray. They have two fins extending from parts of their body that sort of “stick out of the side” and appear to be like webbed feet with which they walk. Actually, there are these small, modified fins on the ventral side that are used to walk on the bottom – they are bottom dwelling (benthic) fish for sure. Like their relatives the frogfish they have a modified spine that is used like a fishing lure. Like the frogfish, the shape of that lure can be used to identify species. But unlike the frogfish the lure is located between their mouth (which near the bottom of the body and is very small) and a pointed rostrum that extends from the top of their head like a battering ram. This lure is extended to lure not fish swimming above, as with the frogfish, but small creatures in and on the sand. Because of this they do not call the lure an illicium but a esca. These are strange looking fish.
Hoese and Moore list four different species and indicate there are at least three others in the Gulf of Mexico. Most are associated with the continental shelf of the Gulf and not inland where we might see them snorkeling around. A couple of species are more associated the continental slope, which drops from the continental shelf to the deep sea. But the Polka-dot batfish (Ogocephalus cubifrons) is reported as being inshore and is the species I have encountered.
Many species are only described as being from the shelf of the Gulf of Mexico and no other oceans. Some of them are even more restricted to either the eastern or western Gulf. This all suggests that batfish do have biogeographic barriers of some sort restricting their dispersal. Being offshore benthic fish, your first guess would be substrate. Usually in those locations the temperature and salinities are pretty similar but the material on the bottom (rock, shell, sand, canyons, etc.) are not. However, several articles mention that batfish can be found over rocky or sandy bottom2,3,4 and the polka-dot batfish can be found in grassbeds as well2. So, I am not sure what the possible barrier is, but several do have a limited range. The east-west split could very well be the DeSoto Canyon off the coast of Pensacola.
All of that said, it is a very interesting group of fish that for one species you might encounter while out and about snorkeling or diving in the Florida panhandle.
References
1 Hoese, H.D., Moore, R.H. 1977. Fishes of the Gulf of Mexico; Texas, Louisiana, and Adjacent Waters. Texas A&M Press. College Station, TX. Pp. 327.
2 Ogocephalus cubifrons, Polka-dot batfish. 2017. Discover Fishes. Florida Museum of Natural History. https://www.floridamuseum.ufl.edu/discover-fish/species-profiles/ogcocephalus-cubifrons/.
3 The Red-lipped Batfish. 2014. Ashland Vertebrate Biology. Ashland University, Ohio. http://ashlandvertbio.blogspot.com/2014/12/the-red-lipped-batfish.html.
4 Cocos Batfish, Ogocephalus porrectus. 2015. Smithsonian Tropical Research Institute. https://biogeodb.stri.si.edu/sftep/en/thefishes/species/777.
by Rick O'Connor | Dec 10, 2021
Most people would agree that this is one of the best times of the year. Christmas brings great music, great cooking, great family gatherings, and… great lights. The lighting of Christmas is one of the more beautiful parts of these celebrations and as I thought about Christmas and writing about nature I thought of those lights.
There is nothing like Christmas lights on a tree.
Photo: Molly O’Connor
Nature can produce beautiful lights as well. Mostly found in the ocean – “phosphorus”, as many called it when I was growing up here, is a beautiful spectacle. It is hard to see with our artificial lights but in the warmer months of summer at locations far from the artificial lights of people, the sea glows a blue-green color that is amazing. Many see this light as sparkles in the water as the waves roll by. Others see it as a stream of light as a fish, or something else, moves around. In the right conditions, you can see your footprints glow as you step in the wet sand. I remember diving at night under the Bob Sikes Bridge once in the 1970s when the bridge, and all of the divers, were aglow. It was beautiful. This phenomena have amazed scientists for centuries and trying to understand how it is produced was a quest for many.
The term phosphorescence actually means using light to emit light. Turns out that is not what is happening in this case. Scientists found that some creatures posses a group of molecules known as luciferins. The term lucifer means “producing light” or “morning star” and seemed an appropriate name for this group of molecules. When luciferin is oxidized, the transfer of an electron emits a “cool light” – usually blue-green in color. Cool meaning that less than 20% of the emitted light is lost as heat. There is a catalytic enzyme known as luciferase that can increase the speed of this chemical reaction and produce bright light in seconds. Since this light is produced by a chemical reaction it was called “chemiluminescence”. However, since this reaction is produced and controlled by living organisms is more widely known as “bioluminescence”. It is not phosphorescence.
Bioluminescence in the sea.
Photo: North Carolina Sea Grant
There are many creatures that produce bioluminescence. The famous fireflies are one, but most live in the sea. The “phosphorus” we are used to seeing is produced by small single celled plants in a group known as dinoflagellates. When disturbed they emit blue-green light as a flash and then a slow dim. Fish swimming past, waves crashing on the beach, or boat and propeller pushing through the water will disturb them. The warmer the sea, the more dinoflagellates there are, the more amazing the light show is. There are lagoons in the tropical parts of the world where these small plants are trapped due to a small opening in and out of the lagoon. The entire lagoon can light up when the conditions are right.
Noctiluca are one of the dinoflagellates that produce bioluminescence.
Photo: University of New Hampshire.
But it does not stop with dinoflagellates. As you descend into the deep ocean the bioluminescence becomes even more spectacular. All sorts of creatures from jellyfish to squid, to fish, to even fungus and bacteria illuminate. Some species of luminescent marine animals do not produce the light themselves but rather harbor luminescent bacteria on the skin or specially designed skim pockets to hold them. Though blue-green is the dominant color, yellows, oranges, and reds have been produced. It has been suggested that blue-green is much easier to see in the deep so reds and oranges are less likely. That said, it is believed that some marine creatures will produce those colors to assist in capturing prey. They can see the red light, but their prey cannot.
The magical lights of the deep sea.
Photo: NOAA
Either way the illumination of the ocean, like the Christmas illumination of our streets and homes, is beautiful and amazing thing. As you admire the lights on the neighborhood home, find some short videos of bioluminescence online and enjoy the show. Happy Holidays everyone.
by Rick O'Connor | Dec 10, 2021
Hoese and Moore1 describes members of the frogfish family as “grotesque”. Well… maybe. I am not sure I would call them grotesque, but they are sort of gelatinous blobs with reduced or missing scales. They feel sort of “mushy”. They have broad shaped fins and a free dorsal spine that serves as a “fishing rod and lure” called the illicium. Maybe they are a little grotesque…maybe.
Being round with broad fins, this is a very slow swimming fish, if you can call how they move swimming. So, to survive, they must blend in with the environment to avoid predators and wait for their prey to come within range before pouncing on them. The illicium lures prey to within range and their “gulp” is like a vacuum cleaner sucking food out of the water.
The family name for the group is Antennariidae, which is appropriate being they have that fishing lure, and is one of the few fish families whose gill opens are behind the pectoral fin. There are 48 species of frogfish found worldwide and most are tropical and subtropical2. Hoese and Moore1 indicate there are three species found in the Gulf of Mexico and all three can be found along the Florida panhandle.
The most commonly encountered frogfish in our area is the Sargassum fish (Histro histro). This small six-inch fish blends in perfectly with the sargassum mats that float in close to shore. Using its fins to brace itself in the seaweed, this fish uses its illicium to attract a variety of small prey that live in the sargassum community. As the sargassum mats are blown close to shore the sargassum fish will leave and move to another mat further out. Finding them on the beach is rare but snorkeling out to a mat just offshore with a small hand net, you might be able to find one by scooping up some sargassum and taking a look.
This sargassum fish is well camelflouged within this mat of sargassum weed.
Photo: Florda Museum of Natural History
The Singlespot Frogfish (Antennarius radiosus) is even smaller at three inches and is found on hard habitats of the middle continental shelf offshore, but occasionally is found along the coastline.
The Splitlure Frogfish (Phrynelox scaber) is five inches in length and not as common on our shelf as the singlespot frogfish. Those that have been found off our coast were further offshore.
The Florida Museum of Natural History includes the Striated Frogfish (Antennarius striatus) as a Gulf species and resident of panhandle waters3.
The distribution of this group is pretty wide throughout the tropical and subtropical waters of the Atlantic Ocean and beyond – suggesting few geographic barriers to dispersal. The sargassum fish, of course, is restricted where sargassum is found – but sargassum is found in a lot of places. The singlespot frogfish seems to have a more restricted home range found in Bermuda, the Atlantic coast of Georgia and Florida, and the Gulf of Mexico. Hoese and Moore does not report this fish in other parts of the Caribbean as the others are1.
They may be grotesque to some, but to others it is an amazing group of fish, much fun in an aquarium, and exciting to find when snorkeling or diving.
1 Hoese H.D., Moore R.H. 1977. Fishes of the Gulf of Mexico; Texas, Louisiana, and Adjacent Waters. Texas A&M University. College Station TX. Pp. 327.
2 Family Antennariidae – Frogfish. 2012. FishBase. https://www.fishbase.de/summary/FamilySummary.php?ID=192.
3 Antennarius striatus. 2017. Discover Fishes. Florida Museum of Natural History. https://www.floridamuseum.ufl.edu/discover-fish/species-profiles/antennarius-striatus/.
by Carrie Stevenson | Jul 29, 2021
Sargassum washed ashore after a storm on Pensacola Beach. Photo credit: Carrie Stevenson, UF IFAS Extension
I am sure it drives the tourists a little crazy. After daydreaming all year of a week relaxing at the beach, they arrive and find the shores covered in leggy brown seaweed for long stretches. It floats in the shallow water, tickling legs and causing a mild panic—was that a fish? A jellyfish? A shark? Then, of course, high tide washes the seaweed up and strands it at the wrack line, shattering the vision of dreamy white sand beaches.
But for those visitors—and locals—willing to take a closer look, the brown algae known as sargassum is one of the most fascinating organisms in the sea. The next time you are at the beach, pick some up and turn it over in your hands. Sargassum is characterized by its bushy, highly branched stems with numerous leafy blades and berry-like, gas-filled structures. The tiny air sacs serve as flotation devices to keep the algae from sinking. This unique adaptation allows it to fulfill a niche at the top of the water column, instead of growing at the bottom or on another organism.
The sargassum fish blends incredibly well into its home within sargassum mats. It uses handlike pectoral fins to move around. Photo credit: Reef Builders
Sargassum tends to accumulate into large mats that drift through the water in response to wind and currents. These drifting mats create a pelagic habitat that attracts up to 70 species of marine animals. Several of these organisms are adapted specifically to life within the sargassum, reaching full growth at miniature sizes and camouflaged in shape, pattern, and color to blend in. These very specialized fauna include the sargassum crab, the sargassum shrimp, sargassum flatworm, sargassum nudibranch, sargassum anemone, and the sargassum fish! The sargassum fish (Histrio histrio) is in the toadfish family, a group of slow-moving reef fish that pick their way through coral and algae by using their pectoral fins like hands. Sea turtle hatchlings will spend their early years feeding and resting within the relative safety of large mid-ocean sargassum mats.
The small air-filled sacs of sargassum allow it to float on the surface, becoming the basis of a teeming ecosystem. Photo credit: Carrie Stevenson, UF IFAS Extension
Over time the air sacs lose buoyancy and the sargassum sinks, providing an important source of food for bottom-dwelling creatures. If washed ashore, many of the animals abandon the sargassum or risk drying out and dying.
In general, most of the larger, familiar seaweeds like sargassum are brown algae. Brown algae (including kelp and rockweed) have colors ranging from brown to brownish yellow-green. These darker colors result from the brown pigment fucoxanthin, which masks the green color of chlorophyll. Extractions from brown algae are commonly used in lotions and even heartburn medication!
by Rick O'Connor | Nov 6, 2020
Seagrasses have been described as the “nursery of the sea”. Studies show that up to 90% of the commercially valuable fin and shellfish species spend part, or all, of their lives in these submerged meadows. As you can imagine, these grasses must grow in clear, relatively shallow waters – so they are more inshore. You might also imagine that most of the fish living here are going to be small. There are the larger predators in this grassy world, but most are going to be small enough to hide amongst the blades.
These inshore seagrass meadows not only provide hiding places but provide food as well. Interestingly, most do not feed on the grass directly, but rather the tiny plants and animals that are attached to the blades – what are called epiphytes and epizoids. Those that feed on these are then preyed upon by slightly large creatures until we find the larger apex predators – like the speckled trout.
Many of those who reside here are specialist in camouflage and mimicry, and others might be ones who actually live in the sand bordering the edge of the meadows – waiting for a chance to pounce on unsuspecting food. Let’s meet a few of these interesting fish.
Photo: Nicholls State University
Pinfish
You are at the beach for a day of fun and sun. You enter the water of Santa Rosa Sound to play at the edge of the seagrass bed, or maybe to snorkel and explore it. As you stand on the sand you feel little nips at your ankles and immediately think – CRAB! But you would be wrong. As you look closer you will see it came from a small fish – and the more you stir the sand, more of these small fish arrive. They are probably feeding on the small invertebrates that are stirred up from your movement, but they periodically nip at you as well.
This small fish is a very common member of the inshore fish community known as the pinfish. They are members of the Porgy family, related to sheepshead, and have incisor teeth for crushing the shells of their prey. Most locals are first introduced to them as a kid while fishing. They seem to bite, or steal, any bait you put on. Most often used as bait themselves, they are actually edible – but you need one of the large ones to have a meal. They get their common name from the sharp spines of their dorsal fin. When snorkeling in the grassbeds you will find they are the most common fish there.
Photo: USGS
Needlefish
These guys look scarier than they are. Long skinny fish with long skinny snouts that hold long skinny teeth. They resemble barracuda and have the look as if they could attack and do some damage – but they are harmless, unless you catch one in a net, then they will swing their long skinny heads towards your hand for snip.
These small predators travel above the grassbeds looking for potential prey hiding among. Small juvenile fish seem to be what they want. Though often just referred to as “needlefish”, there are actually four species, but they are hard to tell apart.
Photo: NOAA
Seahorses
These are captivating fish, and very hard to find as they blend in so well, but they are there – along with their close cousins the pipefish. It seems hard to call it a fish at all – it certainly does not look like one. Swimming vertically in the water, no tail to speak of, they seem like a creature in their own group. But they are fish. The scales are fused into an armor plating and they do have both gills and fins – characteristics of fish. They will use their prehensile tail to grab onto a grass blade, hanging there waiting for tiny shrimp to swim by which they inhale using a vacuum like motion with their tube-shaped mouths.
Pipefish resemble seahorses but are elongated, with a distinct fin for a tail, and swim horizontally as most fish do. They will turn vertically in the grass to appear to be a blade themselves and hunt similar prey as their seahorse cousins.
A well-known characteristic of this group is the fact that the males carry the fertilized eggs – not the females. Males can be identified by the brood sac on their ventral side and they may carry up to 80 eggs. The eggs hatch within the pouch and the young are born alive.
Photo: NOAA
Puffers
This group of fish are famous for their ability to “blow up”, or inflate like a balloon, when threatened. Kids love to play with them and get a kick out of watching them inflate. These are round bodied – slow moving fish, which is one reason they inflate. It does not matter if you can catch them, you cannot swallow them if you do!
There are actually two different families of “blowfish”. The true puffers are smaller (3-12 inches), have tubercles on their bodies instead of long spines, and the teeth in the upper and lower jaw have a space forming four teeth (two on the top jaw, two on the bottom) – giving them their family name “tetradontidae”. The “burrfish” are larger in size (1-2 feet), have long spines on the body, and no median in the teeth – so only one tooth on the top jaw, one on the bottom – “diodontidae”.
The most common one found is the striped burrfish. The big boy of the group – the 2-foot porcupine fish – is rare in the northern Gulf and prefers the reefs of the open sea to grassbeds.
When threatened they will inflate with water (or air) and try to continue swimming. After the danger has passed, they will deflate and go about their merry way. There are stories about their flesh being poisonous and dangerous to eat – it is true. The compound they produce is one of the more toxic found in the fish world. Though there are certified chefs around the world who can safely clean them, it is not recommended you eat these.
by Sheila Dunning | Oct 16, 2020
That’s the question from a recent group exploring what washed up on the beach after Hurricane Sally.
Sea Cucumber
Photo by: Amy Leath
They have no eyes, nose or antenna. Yet, they move with tiny little legs and have openings on each end. Though scientists refer to them as sea cucumbers, they are obviously animals. Sea cucumbers get their name because of their overall body shape, but they are not vegetables.
There are over 1,200 species of sea cucumbers, ranging in size from ¾“ to more than 6‘ long, living throughout the world’s ocean bottoms. They are part of a larger animal group called echinoderms, which includes starfish, urchins and sand dollars. Echinoderms have five identical parts to their bodies. In the case of sea cucumber, they have 5 elongated body segments separated by tiny bones running from the tube feet at the mouth to the opening of the anus. These squishy invertebrates spend their entire life scavenging off the seafloor. Those tiny legs are actually tube feet that surround their mouth, directing algae, aquatic invertebrates, and waste particles found in the sand into their digestive tract. What goes in, must come out. That’s where it becomes interesting.
Sea cucumbers breathe by dilating their anal sphincter to allow water into the rectum, where specialized organs referred to as respiratory trees (or butt lungs) extract the oxygen from the water before discharging it back into the sea. Several commensal and symbiotic creatures (including a fish that lives in the anus, as well as crabs and shrimp on its skin) hang out on this end of the sea cucumber collecting any “leftovers”.
But, the ecosystem also benefits. Not only is excess organic matter being removed from the seafloor, but the water environment is being enriched. Sea cucumbers’ natural digestion process gives their feces a relatively high pH from the excretion of ammonia, protecting the water surrounding the sea cucumber habitats from ocean acidification and providing fertilizer that promotes coral growth. Also, the tiny bones within the sea cucumber form from the excretion of calcium carbonate, which is the primary ingredient in coral formation. The living and dying of sea cucumbers aids in the survival of coral beds.
When disturbed, sea cucumbers can expose their bony hook-like structures through their skin, making them more pickle than cucumber in appearance. Sea cucumbers can also use their digestive system to ward of predators. To confuse or harm predators, the sea cucumber propels its toxic internal organs from its body in the direction of the attacker. No worries though. They can grow them back again.
Hurricane Sally washed the sea cucumbers ashore so you could learn more about the creatures on the ocean floor. Continue to explore the Florida panhandle outdoor.
