OPEN WATER FISH
There is a lot of blue out there. Miles of open water in the Gulf with nowhere to hide… except amongst your own kind. Open water fish with their blue colored bodies, aerodynamically shaped like bullets with stiff angular fins, can zip along in this vast blue openness in large schools. Their myoglobin rich red muscle increases their swimming endurance so they can travel thousands of miles without tiring. Some species are called “ram-jetters”, fish that basically do not stop swimming. They roam the sea looking to eat and to avoid being eaten, following the warm currents in search of their breeding grounds.
The open water is a place for specialists. Most of these fish have small, or no scales, to reduce frictional drag. They have a well-developed lateral line system so when a member of the school turns, the others sense it and turn in unison – just as the six planes in the US Navy Blue Angels delta do. Many are built for speed. Sleek bodies with sharp angular fins and massive amounts of muscle and body mass, some species can reach speeds close to 70 mph. There are fewer species living in the open water but those who do are some of the most prized commercial and recreational fishing targets in the world.
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Greater Amberjack © Carol Cox
When you mention mackerel around here you usually think of one of two fish – the King Mackeral and the Spanish Mackerel. It is actually a large family of open water fish that includes the tuna, bonito, and the wahoo (of Pensacola minor league baseball fame). There are 12 species in this family ranging in size from 1 to 15 feet. A cool thing about this family is that some species can control blood flow and location. This helps them maintain a higher body temperature allowing them to venture into colder waters of the world’s seas.
This family has some of the fastest fish in the sea, and several species are ram-jetters – they almost never stop swimming. Sleek bodies, sharp angular fins, they can be identified by the row of small finlets on the dorsal and ventral sides of their bodies near the rear. Full of red muscle, rich in myoglobin (which can hold more oxygen than hemoglobin alone), these are powerful swimming fish and very popular in the sushi trade. A Bluefin Tuna can be 14 feet long, 800 pounds and bring a commercial fisherman tens of thousands of dollars. Because of this, Bluefin Tuna are internationally protected and managed.
They are one of the big migratory fish, following the large ocean currents for most of their entire lives. Born in the warmer portions of the sea, they grow and feed in the cooler areas, returning in the warmer currents to breed.
Members of the mackerel family have the characteristic dark on top – light one bottom coloration many animals have. This is called counter shading. It is believed to be used as a form of camouflage in the deep blue – with the darker blue-indigo on top (to blend in with the bottom if seen from above) and the lighter silver-white on the bottom (to blend in with the sunlit surface if viewed from below). It is also believed to help with temperature control. The darker side will absorb heat, while the lighter side releases it. Counter shading was used by the US Navy during World War II in an attempt to camouflage planes. If you visit our Naval Aviation Museum, you will see planes from this era are a darker blue on top and a lighter white on bottom.
Mahi–Mahi is the Hawaiian term for a fish whose common name is the dolphinfish. Locals prefer to use its Hawaiian name and that’s what this fish is called at a seafood market or local restaurant. It is a popular food fish, and to have dolphin on the menu or to invite someone to go dolphin fishing would raise eyebrows.
This fish is very different in the sea than on the dinner table. The colors and color changing of the mahi-mahi in the wild is a sight to behold. Some biologists believe the color changing may be some form of communication between members, but the brilliant greens, blues, and yellows are amazing to see. They lose these colors shortly after death, so you must see it to believe it – or settle for one of the popular dolphinfish t-shirts.
Dolphinfish aka Mahi-Mahi
Mullet are bottom feeders. In the near shore Gulf and estuaries, they are more open water than bottom dwellers. Sleek bodied fish with a forked tail and angular fins, they have what it takes to be a fast swimmer. Hanging out around the Sound, you might hear a fish splash. Chances are high that it was a mullet, making a loud splash as they land on their side.
This fish also has a wide tolerance of salinity. Mullet have been found in freshwater rivers and springs and hyper-saline lagoons. They are adaptable, popular food fish that support commercial fisheries in Florida. This is not the case in other parts of the Gulf, since taste depends on food source and water conditions. In a sandy bottom environment (like Santa Rosa Sound), fried mullet is popular as well as mullet roe (eggs), a local form of caviar.
Cobia is one of the migrating fish local anglers gear up for every year during the Cobia run. In the spring when the water temperature turns from 60°F to 70°F, Cobia move along the coastline heading from east to west. They have many different common names along the Gulf Coast including ling, cabio, lemonfish, and sergeant fish –all for the same animal. This is one reason biologists use scientific names – Rachycentron canadum in this case. Whatever you call it, it is popular with the anglers and there is nothing like fresh cobia.
Cobia can get quite large, 5 feet and up to 100 pounds, resembling sharks in the water and sometimes mistaken for them. Cobia seem to like drifting flotsam where potential prey may hangout. Fishermen will toss bait all around the school of cobia trying to get them to snag one.
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Cobia © Carol Cox
Jacks are the largest open water family of fish in the northern Gulf with 24 species. Not all jacks are open water, many are found on reefs and in estuaries. These are aerodynamic shaped fish with small scales and angular fins, built for the open water environment. They vary in size from less than one foot to over three. Jacks are identified by the two extended spines just in front of their anal fin. Several species, such as the Amberjacks, Pompano, and Almaco Jacks, are prized food fish. Others, like the Jack Crevalle and the Blue Runner, are just fun to catch. They put up a great fight. Jacks are schooling fish and often associated with submerged wrecks and reefs, where prey can be found. As with many other open water predators, they will sometimes work in a team to scare and scatter individuals from the safety of their school.
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Amberjacks © Carol Cox
Flying Fish do not actually fly – they glide. These tube-shaped speedy fish have elongated pectoral fins, reaching half the length of their bodies. The two lobes of their forked tail are not the same length. The lower lobe is longer. Using this like a rudder, they gain speed near the surface and leap – extend the large pectoral fins, and glide above the water – up to 100 yards. This maneuver is to avoid the sleek speedy open water predators coming after them. There are eight species of these amazing fish in the Gulf of Mexico ranging in size from 6-16 inches. Most never come within 100 miles of the coast, but a few will, and have even be seen near the pass into Pensacola Bay.