Creatures of the Deep
Fishes and invertebrates of the deep reefs
Deep reef habitats can be composed of coral-built mounds, rocky ledges, and even shipwrecks and are an important component of the Gulf of Mexico. Fishes and invertebrates that occupy these deep reefs are diverse, some are economically important, and many depend exclusively on these ecosystems.
Graphic above was developed by the Gulf of Mexico Fishery Management Council and the University of North Carolina Wilmington with funding under NOAA FY2013 Cooperative Agreement No. NA11NMF4410063
1. Red bream (Beryx decadactylus): This fish, also called an alfonsino, is commercially important in many parts of its range. It occurs worldwide between 330 and 3300 ft. and is usually found between 1000-2000 ft. It prefers rugged, high profile, reef-like habitats where it sometimes occurs in large numbers. It moves from the seafloor up into the water column at night to feed on crustaceans, squids, and small fishes.
2. Snowy grouper (Hyporthodus niveatus): Snowy grouper is a commercially and recreationally important deep reef fish that is susceptible to overfishing. They have been recorded from 65 to 1725 ft. and are most commonly found in depths of 330-1000 ft. It ranges from off the coast of Massachusetts through the Gulf of Mexico and along the Central and South American coasts. Snowy grouper is a top predator, eating mostly fishes, squids, and crabs. Snowy grouper can live to about 30 years old and in US waters spawn between April and July. As in most groupers, it changes sex from female to male as it matures.
3. Conger eel (Conger oceanicus): Conger eels are frequently observed in deep reef habitats, usually sheltering in holes and crevices and can be found off Cape Cod along the US east coast to the north-central Gulf of Mexico and from the estuaries to at least 1900 ft. depths. Fishes make up most of the conger eel’s diet. Like most eels, the larvae of congers are very different from the adults and are long, thin and almost completely transparent. Adults may grow to over 6.5 feet long, and in some places conger eels are valued as food fish.
4. Scorpionfish, deep-water (Idiastion kyphos): Very little is known about this small deep-water scorpionfish. It was only recently observed on deep reefs of the Gulf of Mexico and has also been reported from deep reefs off the southeastern US coast, scattered locations in the Caribbean Sea, and off Venezuela in depths of 750-2050 ft. The scarcity of information on these fish is likely because they hide in coral and rocks, making them hard to sample.
5. Sea fan (Plumarella spp.): Several species of corals in this genus occur on deep reefs from North Carolina to the Straits of Florida and into the eastern Gulf of Mexico in depths of about 600 to 3000 ft. Although little is known of the life history of these octocorals, they add structure to the deep reefs that benefits other animals.
6. Glass sponge (Aphrocallistes beatrix): This deep-water sponge is called a glass sponge because it has a translucent body and its structure is composed of spines made of silicon. It is often covered by attached yellow soft corals. It occurs on deep reefs on both sides of the North Atlantic Ocean, and in the western Atlantic it occurs from North Carolina into the central and eastern Gulf of Mexico to Brazil. Glass sponges may live for hundreds of years, and some species have chemical compounds that have medicinal benefits. Although there is very little data on the biology and ecology of this sponge, it contributes to the habitat complexity of deep reefs.
7. Cup coral (Thecopsammia socialis): This small, mostly yellow/orange hard coral has a single polyp, unlike colonial corals, which are aggregations of many polyps. It lives on rocks and dead corals in a depth range of about 700 to 3000 ft. and has been observed off North Carolina to the eastern Gulf of Mexico. Almost nothing is known of its biology and ecology.
8. Shortbeard codling (Laemonema barbatulum): This fish, related to cods, occurs from Canada through the central and eastern Gulf of Mexico and off northern Brazil from 160 to 5300 ft. (most common from 1000-1300 ft.). There is little known of the life history of this species, but it commonly occurs on deep reef, canyon, and nearby habitats. It is one of the more abundant bottom fishes of the continental slope.
9. Armed nylon shrimp (Heterocarpus ensifer): In some parts of its range this small shrimp may have potential commercial importance but generally not in US waters. It occurs widely in the North Atlantic Ocean and other oceans, and in the western Atlantic it has been recorded from North Carolina to Brazil, including the Gulf of Mexico, most common in 1000-2000 ft. depths. While mostly known to live on sand or mud bottom, it has also been commonly observed around deep reefs off the southeastern US and in the eastern Gulf of Mexico. Females grow to larger sizes than males and have bright blue eggs that are spawned over a long period of time.
10. Living Lophelia, white (Lophelia pertusa): This hard, branching, colonial coral occurs nearly world-wide and is the most common structure forming deep-sea coral. In addition to attaching to rocks and unnatural structures (shipwrecks, oil platforms), it forms mounds and ridges that can be over 330 feet tall. It is the foundation for many deep reefs, creating significant complex habitat that other animals use. In US waters, Lophelia is most common off the southeastern US and in the north-central to eastern Gulf of Mexico from about 650 to 2600 ft. The living coral is bright white because, unlike many shallow corals, it does not have a symbiotic partnership with algae. Though hard, Lophelia is also brittle and can be damaged easily.
11. Gaper (Chaunax pictus): These globular red fish are often observed perched on reef-like habitats of the continental slope. In the western Atlantic, they occur from South Carolina to the eastern Gulf of Mexico to Guatemala, including the Bahamas and the Caribbean Sea in depths from 900-2600 ft. There is little known of the biology and ecology of this fish, but it is likely an ambush predator hiding and waiting until prey swim too close, or it may even attract prey.
12. Swallowtail bass (Anthias woodsi): This beautiful fish, related to groupers, occurs on continental slope reefs off Virginia through the southeastern US and into the eastern Gulf of Mexico in depths of 300-1500 ft. Like the groupers, it is likely hermaphroditic, but little else is known of this secretive species.
13. Thorny tinselfish (Grammicolepis brachiusculus): A goofy looking fish, the thorny tinselfish is often observed swimming about the deep reefs, sometimes in small schools. It has a world-wide distribution, but in the western Atlantic it ranges as far north as Georges Bank and south into the north-central and eastern Gulf of Mexico from 800 to 3000 ft. It seems to be more common on deep reefs of the Gulf of Mexico than deep reefs elsewhere. As with many deep-water species, little is known of its ecology or biology.
14. Rosy dory (Cyttopsis rosea): The rosy dory has a large world-wide distribution. In the western Atlantic, it occurs from Canada and the southeastern US through the northern Gulf of Mexico and into the western Caribbean to northern South America in 500 to 2400 ft. depths. It feeds on small fishes and swimming crustaceans. It is usually seen alone over both reef and sandy habitats.
15. Golden crab (Chaceon fenneri): Golden crab support a small commercial trap fishery in the Atlantic Ocean off Florida, though some may be caught in the Gulf of Mexico. This large crab occurs from the southeastern US to Brazil. It appears to be drawn to deep rocky and coral habitat, where it often buries deep within the coral matrix. It is suspected that golden crab have a smaller population than other similar crabs.
16. Zigzag coral (Madrepora oculata): This fragile, colonial stony coral is often pink colored and can be attached to rocks or to dead Lophelia coral. It provides significant reef structure in some locations but does not form the large reefs or bioherms like Lophelia. It occurs on both sides of the Atlantic and in the western Atlantic from North Carolina through the Gulf of Mexico and in the Caribbean Sea south to Brazil. Its overall depth distribution is 180-6400 ft., but is usually deeper than 1000 ft. in the Gulf and off the southeastern US.
17. Dead Lophelia, brown (Lophelia pertusa): As Lophelia grows and ages the lower branches often die, sometimes because they are smothered by sediments. This is a natural process and does not necessarily signal a problem for these reefs but, the ecology of Lophelia is not well understood. This dead framework provides hiding places for various animals and attachment sites for other corals and sponges.
18. Goosefish, deep-water (Lophiodes beroe): There are several species of deep-water goosefishes, but this species seems to be most common on the deep reefs, ranging from North Carolina to the northeastern Gulf of Mexico and along the western Caribbean Sea to northern South America in depths of 1130-2825 ft. This well camouflaged fish with a huge mouth is in the angler fish family. It sits and waits for prey to swim by; it uses the long lure on the top of its head to attract prey. This species is more abundant than once thought, but its biology and ecology are still poorly understood.
19. Bluntsnout grenadier (Nezumia sclerorhynchus): Primarily occurring off the US east coast and in the eastern Atlantic, this rattail species was only recently observed in the eastern Gulf of Mexico. It can occur in a depth range of 425 to 3600 ft. and is most common in 1475-2400 ft. It tends to be more frequent over complex, reef-like habitats, and it consumes a variety of small crustaceans and worms.
20. Blackbelly rosefish (Helicolenus dactylopterus): Blackbelly rosefish is named for the black internal lining of the belly which cannot be seen externally. This is one of the most common fishes on the continental slope and is commercially important in some parts of its range. It occurs on both sides of the Atlantic, in the western Atlantic from Canada through the northern Gulf of Mexico and along the western Caribbean to Argentina, usually in 360-2410 ft. depths. Although it is often seen on sandy bottoms, it seems most abundant on complex habitats, where it perches on the bottom awaiting prey to swim by. It can live to be nearly 40 years old, and it feeds on a wide variety of bottom and near bottom invertebrates and fishes.
21. Squat lobster (Eumunida picta): This distinctive squat lobster is one of the most common of the larger deep reef invertebrates. It occurs from off Massachusetts through the Gulf of Mexico and western Caribbean to Columbia over a depth range of about 275 to 7215 ft. It is often seen perching motionless with claws outstretched as high as possible on rocks or deep coral branches, and it catches fishes, squids or other animals that swim too close.
22. Roughskin dogfish (Cirrhigaleus asper): The roughskin dogfish has a world-wide distribution, and in the western Atlantic occurs from off North Carolina to southern Florida, scattered locations in the Gulf of Mexico and Caribbean, and off southern Brazil and Argentina in depths of 240 to 2000 ft. It is likely to be found in more of the western Atlantic than is currently known but, it is difficult to collect because of its association with deep reefs. It rarely grows beyond three feet in length and is likely a top predator on deep reefs, feeding mostly on fishes, squids and octopi.
23. Western roughy (Hoplostethus occidentalis): In the same genus as the commercially important orange roughy (H. atlantica), this small roughy can be abundant on deep reefs of the region. This fish only occurs in the western North Atlantic where it is known from the Gulf of Maine, off the southeastern US, into the north-central and eastern Gulf of Mexico, and the western Caribbean to northern South America in 450-1800 ft. depths. Its lack of commercial importance and the limited data on the species are because it is difficult to capture in its deep reef habitat. It generally feeds on small crustaceans and probably migrates up into the water column at night to feed, like many other roughies.
24. Barrelfish (Hyperoglyphe perciformis): Barrelfish occur from the Gulf of Maine (rare) along the US east coast to the north-central Gulf of Mexico. The juveniles occur at the surface often taking shelter under floating plants or debris (like barrels, hence the common name), but adults occupy near-bottom waters to about 1312 ft. This free swimming fish is often seen in schools around Gulf deep reefs. It feeds on small fishes and various invertebrates. Barrelfish can grow to about three feet in length and have minor commercial value as food fish.
25. Darwin’s slimehead (Gephyroberyx darwinii): This roughy species is larger than the western roughy and is commonly observed around rocky deep reefs where it takes shelter in holes and crevices. It could have potential commercial interest but is generally not seen in great abundance. It has a world-wide distribution and in the western Atlantic occurs from the Gulf of Maine through the southeastern US, the north- central and eastern Gulf of Mexico, the Caribbean and northern South America. Its depth range is from 230 to 2100 ft., and it is most common from 650-1650 ft. It eats mostly small shrimps and fishes.