by Rick O'Connor | Apr 5, 2020
We began this series on the Gulf talking about the Gulf itself. We then moved to the big, more familiar – maybe more interesting animals, the vertebrates – birds, fish, etc. In this edition we shift to the invertebrates – the “spineless” animals of the Gulf of Mexico. Many of them we know from shell collecting along the beach, others are popular seafood choices, but most we know nothing about and rarely see.
A spineless Comb Jelly.
Florida Sea Grant
They are numerous, on diversity alone – making up 90% of the animal kingdom. They may leave remnants behind so that we know they are there. They may be right in front of our faces, but we do not know what we are looking at. They are incredibly important. Providing numerous nutrient transport, and transfer, in the ecosystem – that would otherwise not exist. They also provide a lot of ecological services that reduce toxins and waste. One source suggests there are over 30 different phyla and over one million species of invertebrates. In this series we will cover six major groups and we begin with the simplest of them all… the sponges.
For some, you may not know that sponges are actually alive. For others, you knew this but were not sure what kind of creature it was. Are they plants? Animals? Just a sponge?
The answer is animal. Yea…
We usually think of animals as having legs, running around, eating things and defecting in places – the kinds of things that make good animal planet shows.
Sponges… would not make a great animal planet show. What are you going to watch? They appear to be doing nothing. They sit on the ocean floor… and… well… that’s it, they sit on the ocean floor. But they actually do a lot.
A vase sponge.
Florida Sea Grant
They are considered animal because (a) their cells lack a cell wall – which plants have, and (b) they are heterotrophic… consumers… they have to hunt their food and cannot make it as plants do.
What do they eat?
Plankton. Lots of plankton. Looking at a sponge you would call it one animal, but it is actually a colony of specialized cells working as a unit to survive. There are cells with flagella, called collar cells, that use these flagella to create currents that “suck” water into the body of the creature. This is how they collect plankton. The collar cells live in numerous channels throughout the sponge body connected to small pores all over the service of the sponge. This is where they get their phylum Porifera. As the water moves through the channels, the collar cells remove food and specialized cells called choanocytes release reproductive eggs called gemmules. All of the water eventually collects in a cavity, called the gastrovascular cavity where it exists the sponge through a large opening called an osculum.
This is how they eat and reproduce.
The anatomy of a sponge.
Flickr
The matrix, or tissue, of the sponge is held together by small, hard structures called spicules. It sort of serves as a skeleton for the creature. In different sponges the spicules are made of different materials, and this is how the creatures are divided into classes. Some are made of calcium carbonate, like seashells. Others are made of silica and are “glass-like”, and some made of a softer material called “spongin”, which are the ones we use to take baths with. Today purchased sponges are synthetic, not natural – but you can still get natural sponges.
Many sponges are tiny, others are huge. They all like seawater – not big fans of freshwater – and many produce mild toxins to defend the from predators. They do have predators though – hawksbill sea turtles love them. There is currently a lot of research going on using sponge toxins to kill cancer cells. Who knows, the cure to some forms of cancer may lie in the cavity of the sponge.
Another cool thing about them is that their cavities provide a lot of space for other small creatures in the ocean. Numerous species can be found in sponge tissue and cavities, utilizing this space as a habitat for themselves.
Florida Sea Grant
They are a major player in the development of reefs in the tropics and, like their counter parts coral, have experienced a decline due to over harvesting and harmful algal blooms. There are efforts in the Florida Keys to grow new sponge in aquaculture facilities and “re-plant” in the ocean. In the northern Gulf they are more associated with seagrass beds.
These are truly amazing creatures and the more we learn about them, the more amazing they become.
References:
Myriad World of the Invertebrates. EarthLife. https://www.earthlife.net/inverts/an-phyla.html.
by Rick O'Connor | Mar 9, 2020
When it comes to charismatic wildlife, there are few that are more than marine mammals. Everyone loves whales and dolphins. Even today, as many years as I have been working on the water, my colleagues and myself still get excited when we see dolphins. Seeing a whale is like a life-long bucket item. Marine mammals are pretty exciting to see.
A group of small dolphin leap from the ocean.
Photo: NOAA
In the world of marine mammals there are four different groups. Of course, there are the whales and dolphins (the cetaceans), there are the seals and sea lions (pinnipeds), the manatees (sirenians), and… believe it or not… the polar bear (ursids). But we only find two of these in the Gulf of Mexico. The polar bear, of course, does not live here. I know you needed to hear that from me. Pinnipeds no longer live here. Many may be surprised that there was once the Caribbean Monk Seal. There are records of this animal in the southern Gulf, but it is now extinct. There are records of California Sea Lions in the Gulf, possible release from some aquarium program – who knows, but no one has seen any in decades and it is believed they no longer exist here. So that leaves the cetaceans and the manatee.
The most recent publication (2017) states there are 28 species of cetaceans in the Gulf of Mexico. Cetaceans are subdivided into two groups: the baleen and the toothed whales. It is believed that 27 of the 28 species in the Gulf are toothed whales. Baleen whales are the big boys, 50-100’ in length and weighing tons. Some are the largest animals that ever existed on our planet. Most prefer cooler waters. Records of species come from whaling logs of the 19th and early 20th century as well as more recent scientific surveys and records from the Texas Marine Mammal Stranding Network. Early records suggest that right whales, humpbacks, sei, and even blue whales have been seen – though most of these were from the southern Gulf. But more recent science surveys indicated that only the Bryde’s Whale is encountered, and those are not common.
The majority are toothed whales. These would include the largest of them the sperm whale. Made famous in the novel Moby Dick, sperm whales were sought by whalers for their blubber and spermaceti. The blubber was boiled down to oil and used to light street lanterns and light houses. The spermaceti was used for a variety products including cosmetics. The sperm whales in the Gulf appear to be smaller than their counterparts in the open ocean and may be a separate subspecies. They seem to linger off the coast of Texas and Louisiana feeding on squid found at great depths.
The large head and double blowhole of a Bryde’s whale.
Photo: NOAA
Another toothed whale reported is the Orca, or killer whale. These are rare and are most often spotted in the central portion of the Gulf. There are numerous beaked whales and dolphins, but – though reported in early whaling logs – recent surveys suggest there are no porpoise. Porpoise differ from dolphin both in size and tooth shape. The most abundant dolphin is the pantropical spotted dolphin. Those who lived in the area in the 1980s and early 1990s might remember a stranding of dolphins that involved an adult female “Mango” and small baby named “Kiwi”. Mango died during recovery, but Kiwi lived for many years at the Gulfarium in Ft. Walton – these were pantropical spotted dolphins. The most familiar, and most often seen, are the Atlantic Bottlenose dolphins. These are a coastal species, many pods living within the estuary itself. They are the stars of many aquarium shows.
As you might guess, toothed whales are all carnivores. They only have canine teeth, so they must swallow their food whole. Their favorites are fish and squid. They have an amazing sense of echolocation that can help them navigate waters, detect prey, and even “stun” prey making it easier to eat. They give live birth as we do, and the calves stay with their mom for about two years learning how to survive. Cetaceans are very social forming groups known as pods. Most pods are dominated by females and young. Only one or two males are present.
A lone manatee spotted in Big Lagoon near Pensacola Pass. Sightings like these are becoming more common.
Photo: Marsha Stanton
Manatees are members of a group called Sirenia. This name comes from the fact that Columbus’ crew thought they were mermaids – “sirens of the sea”. It has been said before, that if they thought manatees were mermaids – their idea of a mermaid, and ours, is very different. That said, that is where they get their name. There are four species of sirenians on our planet, the one found here is the West Indian Manatee. They are found through the Caribbean, South Atlantic, and Gulf of Mexico. It is believed now that there are two subspecies – the Antillean of the Caribbean, and the Florida manatee from our neck of the woods. These are slow moving herbivores who can tolerate freshwater. They have a low tolerance for cold water and seek warm water springs, and the warm water discharges from power plants, during the winter.
Manatees are not as social as cetaceans and are usually not found in large groups unless they gather in warm water spots. Females usually give birth to a single calf which stays with her for about two years. They have flat molars, like cows, and feed on a variety of plants – the source of their other common name… “sea cows”. The numbers of these animals have increased in recent decades, but they are still low, and the animal is still protected. Boat strikes is one of the leading causes of death, though red tide, and cold stunning are also problems. Sightings of these animals in our area are increasing and we are currently tracking encounters at the county extension office. If you see one, please contact Rick O’Connor at the Escambia County Extension Office – (850) 475-5230, or roc1@ufl.edu.
Though the days of “Save the Whales” and “Save the Manatee” are not as common, these animals still face low numbers and problematic encounters with humans. Fishing gear, boat strikes, sounds, all take marine mammals in the Gulf each year. Hopefully we all get to check off seeing one of these magnificent creatures from our bucket list before the end of our time.
Resource:
Wursig, B. 2017. Marine Mammals of the Gulf of Mexico. In: Wards, C. (ed.) Habitats and Biota of the Gulf of Mexico: Before Deepwater Horizon Oil Spill. Springer, New NY.
by Rick O'Connor | Feb 13, 2020
An eastern cottonmouth basking near a creek in a swampy area of Florida.
Photo: Tommy Carter
When you think of reptiles you typically think of tropical rainforest or the desert. However, there is at least one member of the three orders of reptiles that do live in the sea. Saltwater crocodiles are found in the Indo-Pacific region as are about 50 species of sea snakes. There is one marine lizard, the marine iguana of the Galapagos Islands, and then the marine (or sea) turtles. These are found worldwide and are the only true marine reptiles found in the Gulf of Mexico.
Sea turtles are very charismatic animals and beloved by many. Five of the seven species are found in the Gulf. These include the Loggerhead, which is the most common, the Green, the Hawksbill, the Leatherback, and the rarest of all – the Kemp’s Ridley.
Many in our area are very familiar with the nesting behavior of these long-ranged animals. They do have strong site fidelity and navigate across the Gulf, or from more afar, to their nesting beaches – many here in the Pensacola Beach area. The males and females court and mate just offshore in early spring. The females then approach the beach after dark to lay about 100 eggs in a deep hole. She then returns the to the Gulf never to see her offspring. Many females will lay more than one clutch in a season.
The largest of the sea turtles, the leatherback.
Photo: Dr. Andrew Colman
The eggs incubate for 60-70 days and their temperature determines whether they will be male or female, warmer eggs become females. The hatchlings hatch beneath the sand and begin to dig out. If they detect problems, such as warm sand (we believe meaning daylight hours) or vibrations (we believe meaning predators) they will remain suspended until those potential threats are no more. The “run” (all hatchlings at once) usually occurs under the cover of darkness to avoid predators. The hatchlings scramble towards the Gulf finding their way by light reflecting off the water. Ghost crabs, fox, raccoon, and other predators take almost 90% of them, and the 10% who do reach the Gulf still have predatory birds and fish to deal with. Those who make it past this gauntlet head for the Sargassum weed offshore to begin their lives.
These are large animals, some reaching 1000 pounds, but most are in the 300-400 pound range, and long lived, some reaching 100 years. It takes many years to become sexually mature and typically long-lived / low reproductive animals are targets for population issues when disasters or threats arise. Many creatures eat the small hatchings, but there are few predators on the large reproducing adults. However, in recent years humans have played a role in the decline of the adult population and all five species are now listed as either threatened or endangered and are protected in the U.S. There are a couple of local ordinances developed to adhere to federal law requiring protection. One is the turtle friendly lighting ordinance, which is enforced during nesting season (May 1 – Oct 31), and the Leave No Trace ordinance requiring all chairs, tents, etc. to be removed from the beach during the evening hours. There are other things that locals can do to help protect these animals such as: fill in holes dug on the beach during the day, discard trash and plastic in proper receptacles, avoid snagging with fishing line and (if so) properly remove, and watch when boating offshore to avoid collisions.
If we include the barrier islands there are more coastal reptiles beyond the sea turtles. There are freshwater ponds which can harbor a variety of freshwater turtles. I have personally seen cooters, sliders, and even a snapping turtle on Pensacola Beach. Many coastal islands harbor the terrestrial gopher tortoise and wooded areas could harbor the box turtles. In the salt marsh you may find the only brackish water turtle in the U.S., the diamondback terrapin. These turtles do nest on our beaches and are unique to see. Freshwater turtle reproductive cycles are very similar to sea turtles, albeit most nest during daylight hours.
An American Alligator basking on shore.
Photo: Molly O’Connor
The American alligator can also be found in freshwater ponds, and even swimming in saltwater. They can reach lengths of 12 feet, though there are records of 15 footers. These animals actually do not like encounters with humans and will do their best to avoid us. Problems begin when they are fed and loose that fear. I have witnessed locals in Louisiana feeding alligators, but it is a felony in Florida. Males will “bello” in the spring to attract females and ward off competing males. Females will lay eggs in a nest made of vegetation near the shoreline and guard these, and the hatchlings, during and after birth. They can be dangerous at this time and people should avoid getting near.
We have several native species of lizards that call the islands home. The six-lined race runners and the green anole to name two. However, non-native and invasive lizards are on the increase. It is believed there are actually more non-native and invasive lizards in Florida than native ones. The Argentina Tegu and the Cuban Anole are both problems and the Brown Anole is now established in Gulf Breeze, East Hill, and Perdido Key – probably other locations as well. Growing up I routinely find the horned lizard in our area. I was not aware then they were non-native, but by the 1970s you could only find them on our barrier islands, and today sightings are rare.
An eastern cottonmouth crossing a beach.
Photo: Molly O’Connor
Then there are the snakes.
Like all reptiles, snakes like dry xeric environments like barrier islands. We have 46 species in the state of Florida, and many can be found near the coast. Though we have no sea snakes in the Gulf, all of our coastal snakes are excellent swimmers and have been seen swimming to the barrier islands. Of most concern to residents are the venomous ones. There are six venomous snakes in our area and four of them can be found on barrier islands. These include the Eastern Diamondback Rattlesnake, the Pygmy Rattlesnake, the Eastern Coral Snake, and the Eastern Cottonmouth. There has been a recent surge in cottonmouth encounters on islands and this could be due to more people with more development causing more encounters, or there may be an increase in their populations. Cottonmouths are more common in wet areas and usually want to be near freshwater. Current surveys are trying to determine how frequently encounters do occur.
Not everyone agrees, but I think reptiles are fascinating animals and a unique part of the Gulf biosphere. We hope others will appreciate them more and learn to live with and enjoy them.
by Rick O'Connor | Jan 29, 2020
If you ask a kid who is standing on the beach looking at the open Gulf of Mexico “what kinds of creatures do you think live out there?” More often than not – they would say “FISH”.
And they would not be wrong.
According the Dr. Dickson Hoese and Dr. Richard Moore, in their book Fishes of the Gulf of Mexico, there are 497 species of fishes in the Gulf. However, they focused their book on the fish of the northwestern Gulf over the continental shelf. So, this would not include many of the tropical species of the coral reef regions to the south and none of the mysterious deep-sea species in the deepest part of the Gulf. Add to this, the book was published in 1977, so there have probably been more species discovered.
Schools of fish swim by the turtle reef off of Grayton Beach, Florida. Photo credit: University of Florida / Bernard Brzezinski
Fish are one of the more diverse groups of vertebrates on the planet. They can inhabit freshwater, brackish, and seawater habitats. Because all rivers lead to the sea, and all seas are connected, you would think fish species could travel anywhere around the planet. However, there are physical and biological barriers that isolate groups to certain parts of the ocean. In the Gulf, we have two such groups. The Carolina Group are species found in the northern Gulf and the Atlantic coast of the United States. The Western Atlantic Group are found in the southern Gulf, Caribbean, and south to Brazil. The primary factors dictating the distribution of these fish, and those within the groups, are salinity, temperature, and the bottom type.
Off the Texas coast there is less rain, thus a higher salinity; it has been reported as high 70 parts per thousand (mean seawater is 35 ppt). The shelf off Louisiana is bathed with freshwater from two major rivers and salinities can be as low as 10 ppt. The Florida shelf is more limestone than sand and mud. This, along with warm temperatures, allow corals and sponges to grow and the fish assemblages change accordingly.
Some species of fish are stenohaline – meaning they require a specific salinity for survival, such as seahorses and angelfish. Euryhaline fish are those who have a high tolerance for wide swings in salinity, such as mullet and croaker.
Courtesy of Florida Sea Grant. In total, it takes about 3 – 5 years for reefs to reach a level of maximum production for both fish and invertebrate species.
Forty-three of the 497 species are cartilaginous fish, lacking true bone. Twenty-five are sharks, the other 18 are rays. Sharks differ from rays in that their gill slits are on the side of their heads and the pectoral fins begins behind these slits. Rays on the other hand have their gill slits on the bottom (ventral) side of their body and the pectoral begins before them. Not all rays have stinging barbs. The skates lack them but do have “thorns” on their backs. The giant manta also lacks barbs.
Sharks are one of the more feared animals on the planet. 13 the 25 species belong to the requiem shark family, which includes bull, tiger, and lemon sharks. There are five types of hammerheads, dogfish, and the largest fish of all… the whale shark; reaching over 40 feet. The most feared of sharks is the great white. Though not believed to be a resident, there are reports of this fish in the Gulf. They tend to stay offshore in the cooler waters, but there are inshore reports.
The impressive jaws of the Great White.
Photo: UF IFAS
There is great variety in the 472 species of bony fishes found in the Gulf. Sturgeons are one of the more ancient groups. These fish migrate from freshwater, to the Gulf, and back and are endangered species in parts of its range. Gars are a close cousin and another ancient “dinosaur” fish. Eels are found here and resemble snakes. As a matter of fact, some have reported sea snakes in the Gulf only to learn later they caught an eel. Eels differ from snakes in having fins and gills. Herring and sardines are one of the more commercially sought-after fish species. Their bodies are processed to make fish meal, pet food, and used in some cosmetics. There are flying fish in the Gulf, though they do not actually fly… they glide – but can do so for over 100 yards. Grouper are one of the more diverse families in the Gulf and are a popular food fish across the region. There untold numbers of tropical reef fish. Surgeons, triggerfish, angelfish, tangs, and other colorful fish are amazing to see. Stargazers are bottom dwelling fish that can produce a mild electric shock if disturbed. Large billfish, such as marlins and sailfins, are very popular sport fish and common in the Gulf. Puffers are fish that can inflate when threatened and there are several different kinds. And one of the strangest of all are the ocean sunfish – the Mola. Molas are large-disk shaped fish with reduced fins. They are not great swimmers are often seen floating on their sides waiting for potential prey, such as jellyfish.
We could go on and on about the amazing fish of the Gulf. There are many who know them by fishing for them. Others are “fish watchers” exploring the great variety by snorkeling or diving. We encourage to take some time and visit a local aquarium where you can see, and learn more about, the Fish of the Gulf.
Reference
Hoese, H.D., R.H. Moore. 1977. Fishes of the Gulf of Mexico; Texas, Louisiana, and Adjacent Waters. Texas A&M University Press. College Station Texas. Pp. 327.
by Rick O'Connor | Jan 14, 2020
Standing on one of our local beaches, the Gulf of Mexico appears to be a wide expanse of emerald green and cobalt blue waters. We can see the ripples of offshore waves, birds soaring over, and occasionally dolphins breaking the surface. But few of us know, or think, about the environment beneath the waves where 99% of the Gulf lies. We might dream about catching some of the large fish, or taking a cruise, but not about the geology of the bottom, what the water is doing beneath the waves, or what other creatures might live there.
The Gulf of Mexico as seen from Pensacola Beach.
Photo: Molly O’Connor
Scanning the horizon from the beach, you are gazing at 600,000 square miles of open water. It is about 950 miles from the panhandle to Mexico. Traveling at 10 knots, it would take you about 3 days to cross at its widest point. The Gulf is almost an enclosed body of water. The bottom is somewhat “bowl” shaped with the deepest portion slightly west of center at a location known as the Sigsbee Deep. The island of Cuba serves as the “median” between where the ocean enters and exits the Gulf. Cycling water from the Atlantic crosses from Africa, through the Caribbean, and enters the between Cuba and the Yucatan. The seafloor here sinks and spills into the Sigsbee Deep. The pass between Cuba and Yucatan is about 6500 feet deep and the bottom of the Sigsbee Deep is about 12,000. If you are looking due south from the Florida Panhandle, you would be looking at this pass.
If your gaze shifted slightly to the right – maybe “1:00” – you would be looking at the Yucatan. The Yucatan itself forms a peninsula and a portion of it is below sea level extending further into the Gulf. This submerged portion of the Yucatan is what oceanographers refer to as a continental shelf. On the “leeward” side of the Yucatan Peninsula lies an area of the Gulf known as the Bay of Campeche. There is a shallow section of this “bay” known as the Campeche Banks which supports amazing fisheries and some mineral extraction. Off the Yucatan shelf there is a current of water that rises from the ocean floor called an upwelling. These upwellings are usually cold water, high in oxygen, and high in nutrients – producing an area of high biological productivity and good fishing.
Continuing to circle the Sigsbee Deep and looking about “2:00”, northwest of the Bay of Campeche, you enter the western Gulf which extends from Vera Cruz Mexico to the Rio Grande River in Texas. The shelf is much closer to shore here and the marine environment is still tropical. There is a steep continental slope that drops into the Sigsbee Deep. Water from the incoming ocean currents usually do not reach these shores, rather they loop back north and east forming the Loop Current. The shelf extends a little seaward where the Rio Grande discharges, leaving a large amount of sediment. In recent years, due to human activities further north, water volume discharge here has decreased.
In the direction of about “2:30”, is the Northwestern Gulf. It begins about the Rio Grande and extends to the Mississippi Delta. Here the continental shelf once again extends far out to sea. One of the larger natural coral reefs in the Gulf system is located here; the Flower Gardens. This reef is about 130 miles off the coast of Texas. The cap is at 55 feet and drops to a depth of 160 feet. Because of the travel distance, and diving depth, few visit this place. Fishing does occur here but is regulated. This shelf is famous for billfishing, shrimping, and fossil fuel extraction. The Mississippi River, 15th largest in the world and the largest in the Gulf, discharges over 590,000 ft3 of water per second. The sediments of this river create the massive marshes and bayous of the Louisiana-Mississippi delta region, which has been referred to as the “birds’ foot” extending into the Gulf. This river also brings a lot of solid and liquid waste from a large portion of the United States and is home to one of the most interesting human cultures in the United States. There is much to discuss and learn about from this portion of the Gulf over this series of articles.
The basin of the Gulf of Mexico showing surface currents.
Image: NOAA
At this point we have almost completely encircled the Sigsbee Deep and move into the eastern Gulf. Things do change here. From the Mississippi delta to Apalachee Bay west of Apalachicola is what is known as the Northeastern Gulf – also known as the northern Gulf – locally called the Gulf coast. This is home to the Florida panhandle and some of the whitest beaches you find anywhere. Offshore the shelf makes a “dip” close to the beach near Pensacola forming a canyon known as the Desoto Canyon. The bottom is a mix of hardbottom and quartz sand. Near the canyon is good fishing and this area, along with the Bay of Campeche, is historically known for its snapper populations. It lies a little north of the Loop Current but is exposed to back eddies from it. Today there is an artificial reef program here and some natural gas platforms off Alabama.
Looking between “9:00-10:00” you are looking at the west coast of Florida and the Florida shelf. Here the shelf extends for almost 200 miles offshore. Off the Big Bend the water is shallow for miles supporting large meadows of seagrass and a completely different kind of biology. The rock is more limestone and the water clearer. In southwest Florida the grassflats support a popular fisheries area and a coral system known as the Florida Middle Grounds. At the edge of the shelf is a steep drop off called the Florida Escarpment, which forms the eastern side of the “bowl”. Another ocean upwelling occurs here.
Looking at “11:00” you are looking towards the Florida Keys. Between the Keys and Cuba is the exit point of the Loop Current called the Florida Straits. It is not as deep as here as it is between Cuba and the Yucatan; only reaching a depth of 2600 feet. This is mostly coral limestone and the base of one of the largest coral reef tracks in the western Atlantic. The coral and sponge reefs, along with the coastal mangroves, forms one of the more biological productive and diverse regions in our area. It supports commercial fishing and tourism.
We did not really talk about the bottom of the “bowl”. Here you find remnants of tectonic activity. Volcanos are not found but you do find cold and hot water vent communities, which look like chimneys pumping tremendous amounts of thermal water from deep in the Earths crust. These vent communities support a neat group of animals that we are just now learning about. Brine lakes have also been discovered. These are depressions in the seafloor where VERY salty water settles. These “lakes” have water much denser than the surrounding seawater and can even create their own waves. Many of them lie as deep as 3300 feet and can be 10 feet deep themselves. There is one known as the “Jacuzzi of Despair”. They are so salty they cannot support much life.
In the next addition to this series we will begin to look at the some of the interesting plant and animals that call the Gulf home.
Embrace the Gulf.
by Rick O'Connor | Jan 10, 2020
It’s an amazing place really – the Gulf of Mexico. Covering over 598,000 square miles this almost a complete circle of water and home to some interesting geological features, amazing marine organisms, some of busiest ports in the United States, offshore mineral extraction, great vacation locations, and amazing local culture.
View from the Navarre Beach pier Photo credit: Lydia Weaver
As you stand along Pensacola Beach and look south, you see a wide expanse of water that seems to go on forever. However, in oceanographic terms, the Gulf is not that large of a body of water. Though it is close to 600,000 square miles in size, the Atlantic Ocean is 41,000,000 and the Pacific is 64,000,000 square miles. In addition to area, the mean depth of the Atlantic is a little over 12,000 feet and the Pacific is 14,000 feet. In comparison, the deepest point of the Gulf is 14,000 feet and the mean depth is only 5,000. The shape of the bottom is like a ceramic bowl that was not centered well when fired. The deepest point, the Sigsbee Deep, is about 550 miles southwest (about “2:00” if you are looking from the beach). The shape appears like a hole made by a golf ball that landed in a sand trap. As a matter of fact, there are scientists who believe this is exactly what happened – a large asteroid or comet made have hit the Earth near the Gulf forming a large series of tsunamis and created the Gulf as we know it today.
Either way the “pond” (as some oceanographers refer to it) is an amazing place. The bottom is littered with hot vents, brine lakes, and deep-sea canyons. Large areas of the continental shelf support coral reef formation and a great variety of marine life. Some of the busiest ports in the United States are located along its shores, and it supplies 14% of the wild domestic harvested seafood. Everyone is aware of the mineral resources supplied on the western shelf of the Gulf and the tremendous tourism all states and nations that bordering enjoy.
The emerald waters of the Gulf of Mexico along the panhandle.
This year the Gulf of Mexico Alliance will be celebrating “Embracing the Gulf” with a variety of activities and programs across the northern Gulf region. We will be dedicating this column to articles about the Gulf of Mexico all year and discussing some of the topics mentioned above in more detail. We hope you enjoy your time here and get a chance to explore the Gulf’s seafood, fishing, diving, marine life, ship cruises, unique cultures, and awesome sunsets. Embrace the Gulf!
