by Rick O'Connor | Nov 4, 2021
At the time of this writing, red tide is still lingering off the Pensacola coast. By the time this is posted it may or may not be. I have had a few questions about red tide while this has been occurring here, and some misconceptions about it – so, now is a good time to try and set the story straight.
The dinoflagellate Karenia brevis.
Photo: Smithsonian Marine Station-Ft. Pierce FL
Red tide is actually caused by a group of small, single-celled marine plants. The one responsible for the red tide in the Gulf of Mexico is called Karenia brevis. Karenia is a naturally occurring dinoflagellate. If I were to pull a water sample off of Pensacola Beach right now I would find it there – albeit in small concentrations – say 300-500 cells in a liter of water. At these concentrations there are no problems. When we say problems, we mean respiratory problems or fish kills. See, Karenia is a dinoflagellate that when irritated or disturbed, will release a toxin – brevotoxin. This toxin is a neurotoxin that is known to kill fish, sea turtles, and marine mammals at high concentrations – greater than 1,000,000 cells / liter. For humans the issue is more of respiratory and eye irritation. Though consuming filter feeding shellfish, such as oysters and scallops, during a red tide can cause serious gastrointestinal problems and possibly hospitalization in humans. This is why the state closes shellfish harvesting when Karenia concentrations reach 5,000 cells / liter.
What causes Karenia concentrations to increase from 500 cells to 5,000 cells, or even 1,000,000 cells / liter?
The same thing that causes all plants to grow – sunlight and nutrients.
Here is where the first misconception arises.
“Red tides are caused by the increase of nutrients in the ocean due to human activity”.
Not exactly correct. Red tides have occurred in the Gulf of Mexico since the colonial period, and the colonists certainly did not discharge enough nutrients to spawn a red tide bloom. No, these blooms occur naturally. Most form off the coast of southwest Florida. There the continental shelf extends about 200 miles offshore before reaching the slope to the deep sea. At this slope there are upwelling currents bringing nutrients from the seafloor to bath these phytoplankton in the warm Florida sun. This combination, along with some other water chemistry needs, fuel the growth of phytoplankton from a few hundred cells / liter to a few thousand, hundred thousand, or even a million cells / liter – an algal bloom. At concentrations of 1,000,000 cells or more the water actually changes color to reddish – hence the name “red tide”.
However…
Today humans ARE discharging large amounts of organic and inorganic nutrients into local waterways. These eventually make their way to the Gulf and can enhance a natural bloom from say 10,000 cells / liter to over 1,000,000 – we can make the situation worse. This typically happens when offshore winds blow the naturally occurring red tides closer to shore to meet our “cocktail of nutrients” and wa-la – an enhanced bloom with enhanced problems.
Dead fish line the beaches of the Florida Panhandle after a coast wide red tide event in October of 2015.
Photo: Randy Robinson
Here in the northern Gulf the conditions to spawn naturally occurring red tides do not typically exist. What we usually see are the blooms generated in southwest Florida pushed northward but weather patterns. At the time of this writing, Escambia County is experiencing a red tide offshore at background/very low concentrations (0-10,000 cells/liter). Though are no reports of fish kills or respiratory issues in humans, but these are happening to our east in Okaloosa, Walton, Bay, and Franklin counties.
The state is aware of the not only the red tide situation, but other harmful algal blooms occurring around the state and has a task force to try and address these. We, of course, can help by reducing the amount of nutrients (fertilizers) we discharge into our local waterways. This would include not only commercial fertilizers, but any plant and animal waste.
References
Red Tide Current Status. 2021. Florida Fish and Wildlife Conservation Commission. https://myfwc.com/research/redtide/statewide/?utm_content=&utm_medium=email&utm_name=&utm_source=govdelivery&utm_term=campaign.
by Laura Tiu | Sep 9, 2021
A Lionfish Removal and Awareness Day festival volunteer sorts lionfish for weighing. (L. Tiu)
The northwest Florida area has been identified as having the highest concentration of invasive lionfish in the world. Lionfish pose a significant threat to our native wildlife and habitat with spearfishing the primary means of control. Lionfish tournaments are one way to increase harvest of these invaders and help keep populations down. Not only that, but lionfish are a delicious tasting fish and tournaments help supply the local seafood markets with this unique offering.
Since 2019, Destin, Florida has been the site of the Emerald Coast Open (ECO), the largest lionfish tournament in the world, hosted by Destin-Fort Walton Beach and the Florida Fish and Wildlife Commission (FWC). While the tournament was canceled in 2020, due to the pandemic, the 2021 tournament and the Lionfish Removal and Awareness Day festival returned to the Destin Harbor May 14-16 with over 145 tournament participants from around Florida, the US, and even Canada. The windy weekend facilitated some sporty conditions keeping boats and teams from maximizing their time on the water, but ultimately 2,505 lionfish were removed during the pre-tournament and 7,745 lionfish were removed during the two-day event for a total of 10,250 invasive lionfish removed. Florida Sea Grant and FWC recruited over 50 volunteers from organizations such as Reef Environmental Education Foundation, Navarre Beach Marine Science Station and Tampa Bay Watch Discovery Center to man the tournament and surrounding festival.
Lionfish hunters competed for over $48,000 in cash prizes and $25,000 in gear prizes. Florida Man, a Destin-based dive charter on the DreadKnot, won $10,000 for harvesting the most lionfish, 1,371, in 2 days. Team Bottom Time secured the largest lionfish prize of $5,000 with a 17.32 inch fish. Team Into the Clouds wrapped up the $5,000 prize for smallest lionfish with a 1.61 inch fish, the smallest lionfish caught in Emerald Coast Open History.
It is never too early to start preparing for the 2022 tournament. For more information, visit EmeraldCoastOpen.com or Facebook.com/EmeraldCoastOpen. For information about Lionfish Removal and Awareness Day, visit FWCReefRangers.com
“An Equal Opportunity Institution”
by Laura Tiu | Mar 26, 2021
I am a curious person by nature. When I first moved to the Emerald Coast, I had many questions about the area. For example, why do they call this the Emerald Coast? To help answer my questions, I turned to the Destin History and Fishing Museum in Destin, FL. If you haven’t yet visited the museum, I highly recommend it for locals and visitors alike.
It was easy to see why they call this the Emerald Coast once one lays eyes on the beautiful emerald color water. Other questions weren’t so easily explained. For example, I wanted to know why the pass out of Destin Harbor is called the East Pass, when it is clearly on the west side of Choctawhatchee Bay? In fact, in the early 1900’s, the only outlet from the Bay to the Gulf was about 1.5 miles east of where the current pass resides and was called Old Pass Channel. In 1929, a storm sealed off Old Pass Channel and a heavy dose of spring rain raised Choctawhatchee Bay five feet. The threat of flooding inspired four local fishermen to take matters into their own hands and they dug a small trench across Santa Rosa Island to let the water out of the Bay. By the next morning, the trench had significantly widened into the East Pass we have today, connecting Choctawhatchee Bay to the Gulf of Mexico.
However, that still didn’t explain the East Pass moniker. To explain, we need to look west. Choctawhatchee Bay is connected to Pensacola Bay by the Santa Rosa Sound. This narrow passageway is the space between the Santa Rosa Island, a barrier island, and the mainland. In the early 1900’s, many of the goods and services traded between inhabitants in Okaloosa and Walton counties traveled on ships from Choctawhatchee Bay, through the Santa Rosa Sound, and over to Pensacola Bay, instead of going out into the Gulf. The opening between the Sound and Pensacola Bay is the West Pass, and hence the opening between the Sound and Choctawhatchee Bay is the East Pass. Another mystery solved.
If you are interested in knowing more about the history of this area, the Destin History and Fishing Museum is the place to go.
Citation: Morang, A. . A study of geological and hydraulic processes at East Pass, Destin, FL. Accessed: https://apps.dtic.mil/dtic/tr/fulltext/u2/a253890.pdf
“Foundation for a Gator Nation”
by Rick O'Connor | Nov 19, 2020
I think we can all agree it has been one crazy hurricane season. We have gone through the entire alphabet, and much of the Greek alphabet, naming storms – a record 30. Here in Pensacola we had Sally, but we had to prepare for many others that were wobbling around out there. It seemed this year the computer models were struggling predicting landfall locations. The “spaghetti” paths of the recent Eta were all over the Gulf. So, what is going on? It probably has to do with a warmer Gulf but there has to be more to it than that. Some have mentioned that it has been a La Nina year, and that the Gulf is more active during such years. Fair enough… what is the La Nina?
It is the opposite of the El Nino – a term more people have heard of. Okay… what is the El Nino?
The red indicates warm water temperatures. Notice the warm temps in the eastern Pacific – not normal.
Graphic: NOAA
The El Nino is a warming trend observed in the eastern Pacific Ocean every 2-7 years around Christmas time. El Nino… “the child”. There are records of this event going back over a century. It was first noticed by Peruvian fishermen, who fish some of the most productive waters on the planet. These productive waters are fueled by the cold Humboldt Current and an upwelling bringing nutrient rich cold waters from the seafloor. When the El Nino occurs the Humboldt Current warms and “caps” the upwelling from reaching the surface where the food chain can benefit. The fish move away, and the fishermen notice it. When people began to colonize southern California, and began fishing for tuna and sardines, they noticed the same thing. The El Nino moved north of the equator just as it moves south of it.
To better understand this, we will need to know a little about the ocean currents.
The world rotates on its axis every 24 hours – there, we are off to a good start.
The sun’s rays hit the earth more directly in the equatorial part of the planet, making it warmer there.
The cold polar water is more dense and sinks. The warmer equatorial waters move across the surface of the ocean to fill the void left by the sinking polar water. But it does not move in a straight line to that point. The world is turning remember, and this cause the moving water to bend in a curved pattern. The equatorial water moves west by northwest, warming more as it moves. This is the equatorial current. When it reaches Indonesia it is a balmy 80F+ (or so). This is the land of palm trees and coral reefs – “Bali-Hai”.
The equatorial currents of the Pacific.
Image: NOAA
The water now moves north towards Japan and Korea before heading towards Alaska. Here it is called the Kuroshio Current and here it slowly begins to lose its warmth. As it slides beneath Alaska heading for Canada it is called the North Pacific Current, and then becomes the California Current as it passes the western United States heading back towards the equator. Here the water is much cooler (60-70F). There are no coral reefs, but you do find palm trees in southern California. This coast is also bathed with an upwelling and supports a rich fishery.
The southern Pacific is the same – but the current names are different. The equatorial current heads west reaching Indonesia and heads south to Australia where they call it the East Australian Current (the EAC of Finding Nemo fame). This is the home of the Great Barrier Reef. The currents circle near Antarctica, become colder, and head north along South America as the Humboldt Current (also known as the Peru Current).
Now imagine this…
Imagine the warm equatorial water near Indonesia begins to slide back towards California and Central America. Imagine this warm water layer then heads north and south to the coasts of California and Peru. This warm water caps the upwelling and the fish leave – near Christmas time – the El Nino. Bad times for the fishing fleet.
Commercial fishing in the California Current.
Photo: NOAA
The atmosphere responds to these ocean temperature shifts. Normally, the cooler waters reaching the equator from California and Peru move westward forming the equatorial current. This cool water helps form east winds that move across westward as well. Known as the Trade Winds, sailors have used them for centuries to reach “good trading locations”. They are steady and dependable… unless it is an El Nino year. During El Nino the warmer ocean slows the strength of these winds. They actually move eastward across Central America and impact the Gulf of Mexico. During El Nino years these eastward moving Pacific winds push hurricanes out of the Gulf into the Atlantic. These are the hurricane seasons when Bermuda is hit frequently.
La Nina is the opposite. The Pacific waters moving into the equatorial area from California and Peru are colder than normal. These colder waters move faster and farther across the equatorial waters of the Pacific increasing the Trade Winds moving west… not east. With these Trade Winds moving in the direction they should, even stronger than normal, hurricanes are “sucked” into the Gulf of Mexico. La Nina seasons are very busy hurricane seasons for us. And you guessed it, it is a La Nina year. La Nina usually follows the El Nino and we can sometimes experience them for two seasons, but 12 months is typical.
The thing is La Nina’s have been occurring for centuries. We have certainly had hurricane seasons that were busier than normal but not to the extent we saw this year. You have to look at climate change in general, and other atmospheric conditions that could influence this. I am sure the meteorologists and climatologists are as interested in what happened (is happening) this year as we are.
Hopefully we will not see another season like this for some time.
Happy Thanksgiving.
by Rick O'Connor | Oct 16, 2020
When most people think of reefs, they think of the coral reefs of the Florida Keys and Australia. But here in the northern Gulf the winters are too cold for many species of corals to survive. Some can, but most cannot and so we do not have the same type of reefs here.
That said, we do have reefs. We have both natural and artificial reefs. There are natural reefs off Destin and a large reef system off the coast of Texas – known as the “Flower Gardens”. Here the water temperatures on the bottom are warm enough to support some corals. The artificial reef program along the northern Gulf is one of the more extensive ones found anywhere. There is a science to designing an artificial reef – you do not just go out and dump whatever – because if not designed correctly, you will not get the fish assemblages and abundance you were hoping for. But if you do… they will come.
Reefs are known for their high diversity and abundance of all sorts of marine life – including fishes. There are numerous places to hide and plenty of food. Most of the fish living on the reef are shaped so they can easily slide in and out of the structure, have teeth that can crush shell – the parrotfish can actually crush and consume the coral itself, and some can be fiercely territorial. There are numerous tropical species that can be found on them and they support a large recreational diving industry. Let’s look at a few of these reef fish.
Moray eel.
Photo: NOAA
Moray Eels
These are fish of legend. There all sorts of stories of large morays, with needle shaped teeth, attacking divers. Some can get quite large – the green moray can reach 8-9 feet and weigh over 50 pounds. Though this species is more common in the tropics, it has been reported from some offshore reefs in the northern Gulf. There are three species that reside in our area: the purplemouth, the spotted, and the ocellated morays. The local ones are in the 2-3 foot range and have a feisty attitude – handle with care – better yet… don’t handle. They hide in crevices within the reef and explode on passing prey, snagging them with their sharp teeth. Many divers encounter them while searching these same crevices for spiny lobster. There are probing sticks you can use so that you do not have to stick your hand in there. There are rumors that since they have sharp teeth and tend to bite, they are venomous – this is not the case, but the bite can be painful.
The massive size of a goliath grouper. Photo: Bryan Fluech Florida Sea Grant
Groupers
This word is usually followed by the word “sandwich”. One of the more popular food fish, groupers are sought by anglers and spearfishermen alike. They are members of the serranid family (“sea basses”). This is one of the largest families of fishes in the Gulf – with 34 species listed. 15 of these are called “grouper” and there have been other members of this family sold as “grouper”.
So, what is – or is not – a “grouper”. One method used is anything in the genus Epinephelus would be a grouper. This would include 11 species, but would leave out the Comb, Gag, Scamp, Yellowfin, and Black groupers – which everyone considers “grouper”. Tough call eh?
These are large bodied fish with broad round fins – the stuff of slowness. That said, they can explode, just like morays, on their prey. Anglers who get a grouper hit know it, and divers who spear one know it. They range in size from six inches to six feet. The big boy of the group is the Goliath Grouper (six feet and 700 pounds). They love structure – so natural and artificial reefs make good homes for them. They also like the oil rigs of the western Gulf.
An interesting thing about many serranids is the fact they are hermaphroditic – male and female at the same time. Most grouper take it a step further – they begin life as females and become males over time.
The king of finfish… the red snapper
Photo: Florida Sea Grant
Snappers
The red snapper is king. Prized as a food fish all over the United States, and beyond, these fish have made commercial fishermen very happy. With an average length of 2.5 feet, some much larger individuals have been landed. This fishery put Pensacola on the map in the early 20th century. Sailing vessels called “Snapper Smacks” would head out to the offshore banks and natural reefs, return with a load, and sell both locally and markets in New York. There are large populations in Texas waters and down on the Campeche Banks off Mexico. “Snapper Season” is a big deal around here.
Though these are reef fish, snapper have a habit of feeding above, and away from, them. You probably knew there was more than one kind of snapper but may not know there are 10 species locally. Due to harvesting pressure, there are short seasons on the famous red snapper – so vermillion snapper has stepped in as a popular commercial fishery – and it is very good also. Some, like the gray snapper, are more common inshore around jetties and seawalls. Also known as the black snapper or mangrove snapper, this fish can reach about three feet in length and make a good meal as well.
The white grunt.
Photo: University of Florida
Grunts
Grunts look just like snapper, and probably sold as them somewhere. But they are a different family. They lack the canines and vomerine teeth the snappers have – other than that, they do look like snapper. Easy to tell apart right? Vomerine are tiny teeth found in the roof of the mouth, in snappers they are in the shape of an arrow. They get their name from a grunting sound they make when grinding their pharyngeal teeth together. A common inshore one is called the “pigfish” because of this. They do not get as large as snapper (most are about a foot long) and are not as popular as a food fish, but the 11 known species are quite common on the reefs, and the porkfish is one of the more beautiful fish you will see there.
Spadefish on a panhandle snorkel reef.
Photo: Navarre Beach Snorkel
Spadefish
This is one of the more common fish found around our reefs. Resembling an angelfish, they are often confused with them – but they are in a family all to themselves. What is the difference you ask? The dorsal fin of the spade fish is divided into two parts – one spiny, the other more fin-like. In the angelfish, there is only one continuous dorsal fin.
Spadefish like to school and are actually good to eat. It is also the logo/mascot of the nearby Dauphin Island Sea Lab.
Gray triggerfish.
Photo: NOAA
Triggerfish
“Danger Will Robinson!” This fish has a serious set of teeth and will come off the reef and bite through a quarter inch wetsuit to defend their eggs. Believe it – they are not messing around. Once considered a by-catch to snapper fishermen, they are now a prized food fish. They are often called “leatherjackets” due to their fused scales forming a leathery like skin that must be cut off – no scaling with this fish. They have the typical tall-flat body of a reef fish, squeezing through the rocks and structure to hide or hunt. We have five species listed in the Gulf of Mexico, but it is the Gray Triggerfish that is most often encountered.
Photo courtesy of Florida Sea Grant
Lionfish
You may, may not, have heard of this one – most have by now. It is an invader to our reefs. To be an invasive species you must #1 be non-native. The lionfish is. There are actually about 20 species of lionfish inhabiting either the Indo-Pacific or the Red Sea region.
#2 have been brought here by humans (either intentionally or unintentionally – but they did not make it on their own) – this is the case with the lionfish. It was brought here for the aquarium trade. There are actually two species brought here: The Red Lionfish (Pterois volitans) and the Devilfish (Pterois miles). Over 95% of what has been captured are the red lionfish – but it really does not matter, they look and act the same – so they are just called “lionfish”.
#3 they must be causing an environmental, and/or an economic problem. Lionfish are. They have a high reproductive rate – an average of 30,000 offspring every four days. There is science that during sometimes of the year it could be higher, also they breed year-round. Being an invasive species, there are few predators and so the developing young (encapsulated in a gelatinous sac) drift with the currents to settle on new reefs where they will eat just about anything they can get into their mouths. There have been no fewer than 70 species of small reef fish they have consumed – including the commercially valuable vermillion snapper and spiny lobster. There is now evidence they are eating other lionfish.
They quickly take over a reef area and some of the highest densities in the south Atlantic region have been reported off Pensacola. However, at a 2018 state summit, researchers indicated that the densities in our area have declined in waters less than 200 feet. This is most probably due to the harvesting efforts we have put on them. They are edible – actually, quite good, and there is a fishery for them. Derbies and ecotours have been out spearfishing for them since 2010. You may have heard they were poisonous and dangerous to eat. Actually, they are venomous, and the flesh is fine. The venom is found in the spines of the dorsal, pelvic, and anal fins. It is very painful, but there are no records of anyone dying from it. Work and research on management methods continue.
