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 | Jul 9, 2021
This is one strange, primitive, dinosaur-looking fish. They have large scutes embedded in their skin that give them an armored look. They are big – reaching 14 feet in length and 800 pounds (though the Gulf sturgeon does not reach the large size of their cousin the Atlantic sturgeon). They resemble sharks with their heterocercal caudal fin and possess long whiskers (barbels) suggesting a benthic mode of feeding.
Sturgeon are large fish. The barbels (whiskers) are for finding prey buried in the sediment. Notice the raised ganoid scales of this ancient creature.
Photo: U.S. Fish and Wildlife Service.
Panhandle residents know them from their impressive leaps as they head upriver for spawning in the spring. The loud splash from one of these leaps can be heard for a long distance and is a concern for boaters who may be zipping up and down one of the local rivers on a jet sky, or even a bass boat. When in college, we asked one of the professors – “why do mullet jump?”. He paused for a second and responded – “for the same reason manta rays jump”. There was another longer pause. Understanding what was going on we took the bait and asked – “okay… why do manta rays jump?” – “we don’t know”. However, that was in 1980 and a lot has been learned since. We know that not only do mullet and mantas leap, but baleen whales and sturgeon do as well. It is believed that baleen whales leap to communicate during the breeding season. Since sturgeon breed in panhandle rivers, it is believed that this is the reason they may do so. Scientists have also found it helps adjust their swim bladders with internal gas making them more buoyant in the water.
Like salmon, sturgeon swim up rivers to breed and spawn in the spring. Fertilization is external and the gray-black eggs are laid on the substrate at the bottom. The newborn and adults spend the remaining spring in the rivers, and the adults do not feed at this time. In summer all head for the estuaries where the adults begin feeding with a vengeance. They feed on a variety of benthic invertebrates and prefer sections of the bay that are well oxygenated. Sturgeon spend the summer and much of the fall in the bays until the temperatures begins to drop at which time they head into the open Gulf of Mexico. The spring, they find their breeding rivers and the reproductive cycle begins again. This is a long-lived fish, reaching up to 50 years in age.
As far as the biogeography of this species, it is an interesting one. They have been around for about 200 million years. This was about the time the whole “Pangea” movement was going on – Florida did not look like Florida then. There was an opening between what is now the southeastern United States and the Florida peninsula. The water moving through this was called the Georgia Seaway or the Suwannee Channel. This allowed marine species to easily move from the Atlantic to the Gulf of Mexico. It was believed the current in this seaway was significant enough to keep silt and clays from reaching what would be become peninsula Florida, which was probably a submerged region of islands at the time.
During those times the Atlantic sturgeon (Acipenser oxyrinchus) inhabited this region, using southeast rivers for breeding. About 25 million years ago global land mass changes began a period of ice formation that encouraged sea level to drop and the peninsula portion of Florida was exposed – the Florida people know today. However, this new peninsula isolated populations of sturgeon (and other fish at that time) from reaching each other. As time moved on, different genetic changes occurred in both populations to produce offspring that varied from each other. These external morphological changes were enough to let you know they were different, but genetically they are close enough to still breed. In these situations, they have deemed “subspecies” of each other. The Atlantic sturgeon (Acipenser oxyrinchus oxyrinchus) and the Gulf sturgeon (Acipenser oxyrinchus desotoi). It is the Gulf sturgeon we find along the panhandle. This process of producing new subspecies and species due to population isolation over time is called speciation.
Another interesting trend is the original range of the Gulf sturgeon was from the Texas/Louisiana border to about Tampa Bay. This suggest that the fish took advantage of numerous rivers for breeding but there was a barrier as you reach the tropics. Whether that barrier was climatic (temperature) biological (food source) or something else I am not sure. With the high concentration of sturgeon in the panhandle you might think they require the alluvial rivers of this region. But sturgeon are as common in tannic rivers, such as the Suwannee and Yellow Rivers, as they are in those alluvial ones, such as the Escambia and Apalachicola.
Today, their range is even smaller. They are now found only in the rivers between Louisiana/Mississippi border to the Suwannee River. This range reduction is probably due to habitat alteration (much of it human induced – such as dams) and overharvesting (the eggs of the sturgeon are used for caviar). Today all species and subspecies of sturgeon are protected by the endangered species act.
Because this is an ancient fish, the biogeographic story of the sturgeon is an interesting one and shows how speciation occurs over time with all life. They are really cool fish and, if you have not seen one leap yet, I hope you get to. It is pretty amazing.
References
Florida’s Geologic History, University of Florida IFAS, https://edis.ifas.ufl.edu/publication/UW208.
NOAA Species Directory, Gulf Sturgeon, https://www.fisheries.noaa.gov/species/gulf-sturgeon.
NOAA Species Directory, Atlantic Sturgeon, https://www.fisheries.noaa.gov/species/atlantic-sturgeon.
Sturgeon, Florida Fish and Wildlife Conservation Commission, https://myfwc.com/conservation/you-conserve/wildlife/sturgeon/#:~:text=When%20the%20ambient%20pressure%20changes,to%20communicate%20with%20other%20sturgeon..
by Erik Lovestrand | Mar 11, 2021
Cobia Researchers use Transmitters as well as Tags to Gather Data on Migratory Patterns
I must admit to having very limited personal experience with Cobia, having caught one sub-legal fish to-date. However, that does not diminish my fascination with the fish, particularly since I ran across a 2019 report from the Gulf States Marine Fisheries Commission titled “Management Profile for Gulf of Mexico Cobia.” This 182-page report is definitely not a quick read and I have thus far only scratched the surface by digging into a few chapters that caught my interest. Nevertheless, it is so full of detailed life history, biology and everything else “Cobia” that it is definitely worth a look. This posting will highlight some of the fascinating aspects of Cobia and why the species is so highly prized by so many people.
Cobia (Rachycentron canadum) are the sole species in the fish family Rachycentridae. They occur worldwide in most tropical and subtropical oceans but in Florida waters, we actually have two different groups. The Atlantic stock ranges along the Eastern U.S. from Florida to New York and the Gulf stock ranges From Florida to Texas. The Florida Keys appear to be a mixing zone of sorts where Cobia from both stocks go in the winter. As waters warm in the spring, these fish head northward up the Atlantic and Gulf coasts of Florida. The Northern Gulf coast is especially important as a spawning ground for the Gulf stock. There may even be some sub-populations within the Gulf stock, as tagged fish from the Texas coast were rarely caught going eastward. There also appears to be a group that overwinters in the offshore waters of the Northern Gulf, not making the annual trip to the Keys. My brief summary here regarding seasonal movement is most assuredly an over-simplification and scientists agree more recapture data is needed to understand various Cobia stock movements and boundaries.
Worldwide, the practice of Cobia aquaculture has exploded since the early 2000’s, with China taking the lead on production. Most operations complete their grow-out to market size in ponds or pens in nearshore waters. Due to their incredible growth rate, Cobia are an exceptional candidate for aquaculture. In the wild, fish can reach weights of 17 pounds and lengths of 23 inches in their first year. Aquaculture-raised fish tend to be shorter but heavier, comparatively. The U.S. is currently exploring rules for offshore aquaculture practices and cobia is a prime candidate for establishing this industry domestically.
Spawning takes place in the Northern Gulf from April through September. Male Cobia will reach sexual maturity at an amazing 1-2 years and females within 2-3 years. At maturity, they are able to spawn every 4-6 days throughout the spawning season. This prolific nature supports an average annual commercial harvest in the Gulf and East Florida of around 160,000 pounds. This is dwarfed by the recreational fishery, with 500,000 to 1,000,000 pounds harvested annually from the same region.
One of the Cobia’s unique features is that they are strongly attracted to structure, even if it is mobile. They are known to shadow large rays, sharks, whales, tarpon, and even sea turtles. This habit also makes them vulnerable to being caught around human-made FADs (Fish Aggregating Devices). Most large Cobia tournaments have banned the use of FADs during their events to recapture a more sporting aspect of Cobia fishing.
To wrap this up I’ll briefly recount an exciting, non-fish-catching, Cobia experience. My son and I were in about 35 feet of water off the Wakulla County coastline fishing near an old wreck. Nothing much was happening when I noticed a short fin breaking the water briefly, about 20 yards behind a bobber we had cast out with a dead pinfish under it. I had not seen this before and was unaware of what was about to happen. When the fish ate that bait and came tight on the line the rod luckily hung up on something in the bottom of the boat. As the reel’s drag system screamed, a Cobia that I gauged to be 4-5 feet long jumped clear out of the water about 40 yards from us. Needless to say, by the time we gained control of the rod it was too late; a heartbreaking missed opportunity. Every time we have been fishing since then, I just can’t stop looking for that short, pointed fin slicing towards one of our baits.
by Chris Verlinde | Mar 5, 2021
On most days, if you walk to the end of the Navarre Beach Fishing Pier, you will find a group of shark anglers that provide valuable data to the National Oceanic and Atmospheric Administration (NOAA) Cooperative Volunteer Shark Tagging program. Led by Earnie Polk, 50-60 team members have participated in the cooperative tagging
program in the twenty-five years he has been involved.
This group not only provides research data to NOAA, but are also stewards of pier etiquette, Navarre Beach and the surrounding area. Tourists and locals alike are treated to stories of local history, fish tales and general information about the area from Earnie and Team True Blue members. In addition, visitors may see a shark tagged and released or the group catching large fish to be used for shark bait
Photo Credit Earnie Polk
The NOAA Cooperative Shark Tagging program has been in existence since 1962. Today thousands of anglers along the Gulf of Mexico and Atlantic Coast have tagged more than 295,000 sharks representing 52 different species. More than 17,500 sharks have been recaptured! This program provides information on shark migration patterns, numbers, locations, migrations, age and growth rates, behavior and mortality.
Earnie estimates he has tagged more than one-thousand sharks for the program. He has refined handling methods to have the least impact on the animal to ensure the survival of the shark after release. The team brings the shark to shore to measure the length and tag the shark just behind the dorsal fin. 
Earnie shared an interesting story about tagging at least eighty Dusky sharks during a red tide event during the late fall of 2015. He noticed as the north winds blew the red tide out, an open area was created along the coast. This allowed clear water for the sharks to travel closer to shore and within distance of the tag and release team.
Today, the tiger shark is the most common shark the team tags and releases. Recently, the team tagged and released a 12’6” tiger shark. Randy Meredith, of the Navarre Newspaper agreed to share the video he edited of the Navarre Fishing Pier and the tag and release of the tiger shark in February 2021.
The team uses heavy gear, 200-pound test line and Everol reels that have drag pressure for a shorter fight to reduce stress on the animal for a better survival rate. Gear is spread along the rails at the end of the pier. Baited lines range from approximately 75 to 400 yards off the end of the pier. You probably wonder how they get their line 400 yards off the pier. Earnie has modified a fiberglass kayak with a battery powered motor. It is lowered to the surface of the water; team members drop their lines onto the kayak and Earnie pilots the kayak out to deeper water. 
Their strategy is that by dropping more lines, at different depths and locations a shark is bound to trip over one of the lines. They use bait they catch on the pier or other fishing trips. Something big had hit on a cow nose ray over the weekend, so most members were using rays for bait. One team member said, “if the fish had hit on a watermelon, we all would be using watermelon for bait.” These guys have a great sense of humor!!
Make sure that the next time you visit Navarre Beach, you take time to walk out to the end of the fishing pier to learn about local sharks, 
history and the area from these interesting, funny and helpful anglers. On clear days you may see sharks, rays, sea turtles and other types of marine life as you venture out.
Be sure to stop at the pier store to pay the $1.00 per-person fee to enjoy the view!
by Mark Mauldin | Feb 5, 2021
Reminder: Spotted seatrout harvest is closed in the Western Panhandle Management Zone the entire month of February.
New regulations were put into place last year reducing bag limits and closing harvest during February in the Western Panhandle Management Zone. For more details see my previous post on the subject.When Spotted Seatrout season is open (months other than February) in the Western Panhandle Management Zone the daily bag limit is 3 per harvester. Harvested Spotted Seatrout must be more than 15 inches long and less than 19 inches long. One fish, per vessel, over 19 inches my be included in the bag limit.
The Western Panhandle Spotted Seatrout Management Zone includes the State and federal waters of Escambia County through the portions of Gulf County west of longitude 85 degrees, 13.76 minutes but NOT including Indian Pass/Indian Lagoon.
Boundary between the Western Panhandle and Big Bend spotted seatrout management zones.
Image source: www.myfwc.com
See myfwc.com for complete information on all game and fish regulations in Florida.
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.
