ANGLERFISHES: Lophiiformes

PHYSICAL CHARACTERISTICS

The first spine of the dorsal (DOOR-suhl) fin of anglerfishes serves as a fishing, or angling, rod and lure for attracting prey, animals hunted and caught for food. The dorsal fin is the one along the midline of the back. The fishes use muscles at the base of the rod to move it rapidly, thrashing the lure above or in front of the anglerfish's mouth. In some anglerfishes the lure may be a simple bulb, but in others it is quite elaborate. In many deep-sea anglerfishes, the lure glows. In forms that live in sunlit regions, the lure may resemble a shrimp or even a fish. The bases of the pectoral (PECK-ter-uhl) fins of anglerfishes are so long that the fins appear to be at the end of long, jointed arms. The pectoral fins are the front pair and correspond to the front legs of four-footed animals. The color and size of anglerfishes vary greatly. Many bottom-dwelling anglerfishes have camouflage coloring, but the midwater forms are usually very dark brown or black. The length ranges from a few inches (centimeters) to several feet (about 2 meters).

GEOGRAPHIC RANGE

Anglerfishes live all over the world.

HABITAT

Most anglerfishes live in the deep ocean. Some live in open water in middle depths. Others are bottom dwellers. A few anglerfishes enter shallows, and many live in coral reefs.

DIET

Anglerfishes eat fishes and other animals attracted by the lure. A few anglerfishes feed mainly on bottom-dwelling invertebrates, animals without backbones.

BEHAVIOR AND REPRODUCTION

Anglerfishes ambush their prey. During a typical ambush, the anglerfish remains motionless (either on the bottom or in open water) until it detects prey. When it senses prey, the anglerfish uses its fishing rod to attract the prey to within reach. When the prey reaches the strike zone, the anglerfish opens its mouth rapidly and widely, creating strong suction, which draws in the prey. The entire open, suck, and swallow takes four to seven milliseconds.

Little is known about the reproduction and early life of anglerfishes. Scientists believe that the larvae (LAR-vee) of all anglerfishes drift in open water.

Larvae are animals in an early stage and must change form before becoming adults. Eggs are released from female anglerfishes embedded in a long ribbonlike veil of mucus. This veil can be as long as 39 feet (12 meters) and as wide as 5 feet (1.5 meters) and has been estimated to contain more than 1.3 million eggs. The males of some deep-sea anglerfishes are tiny and permanently attach themselves to the bodies of females.

ANGLERFISHES AND PEOPLE

Some anglerfishes are caught for their meat and for the liver.

WHY IS FISHING CALLED ANGLING?

In the old days in England the word angle meant "fish hook." Angling is the sport of catching fish with a hook, as opposed to a net or one's hands. Anglers are people who like this sport.

THE SARGASSO SEA

The Sargasso Sea is a huge floating island of seaweed (2 million square miles) in a calm area of the Atlantic Ocean near Bermuda.

CONSERVATION STATUS

The World Conservation Union (IUCN) lists one species of anglerfish as Critically Endangered, or facing extremely high risk of extinction in the wild in the near future.

SARGASSUMFISH (Histrio histrio): SPECIES ACCOUNTS

Physical characteristics: Sargassumfish have a short fishing rod and smooth skin. The fish are usually camouflaged with streaks, spots, and mottling of brown, olive, and yellow, making them nearly impossible to detect in the seaweed in which they hide.

Geographic range: Sargassumfish live in the western Atlantic, western Pacific, and Indian oceans.

Habitat: Sargassumfish live only in open warm water on the surface in sargassum. Sargassum is a brown seaweed that is a type of algae (AL-jee), plantlike growths that live in water and have no true roots, stems, or leaves.

Diet: Sargassumfish eat anything they can swallow, including fishes as long as or longer than they are. They even eat other sargassumfish.

Behavior and reproduction: Sargassumfish release eggs in an egg veil 35 to 47 inches (90 to 120 centimeters) long and 2 to 4 inches (5 to 10 centimeters) wide.

Sargassumfish and people: Sargassumfish have no importance to people.

Conservation status: Sargassumfish are not threatened or endangered. ∎

MONKFISH (Lophius americanus): SPECIES ACCOUNTS

Physical characteristics: Monkfish have a very large, wide, flattened head and an enormous mouth armed with long, sharp, cone-shaped teeth. Monkfish have hairlike threads hanging in front of their eyes that act as fishing line. The lines have knoblike lures at the end. Monkfish have a large number of dorsal and anal fin rays and vertebrae (ver-teh-BREE), which are the bones that make up the spinal column.

Geographic range: Monkfish live in the western Atlantic Ocean.

Habitat: Monkfish live on soft and hard bottoms, including mud, sand, pebbles, gravel, and broken shells from just below the tide line to depths of about 2,625 feet (800 meters).

Diet: Monkfish are greedy ambushers that eat any prey large enough to engulf, including fishes nearly as long as they are. Monkfish have been known to engulf birds such as cormorants, herring gulls, loons, and auks. Smaller monkfish feed on a variety of invertebrates.

Behavior and reproduction: Small fish that come in range of the fishing line and lures of monkfish and strike at them are led down the line into the monkfish's huge mouth. Except for the facts that monkfish have long egg veils and the early larvae drift in open water, scientists do not how these fish reproduce.

Monkfish and people: Monkfish is a popular food fish. Some people call it goosefish.

Conservation status: Monkfish are not threatened or endangered. ∎

FOR MORE INFORMATION

Books:

Byatt, Andrew, Alastair Fothergill, and Martha Holmes. Blue Planet. New York: DK, 2001.

Gilbert, Carter Rowell, and James D. Williams. National Audubon Society Field Guide to Fishes: North America. New York: Knopf, 2002.

Web sites:

"City Boat Joins Monkfish Study." South Coast Today.http://www.s-t.com/daily/02-01/02-28-01/a01lo002.htm (accessed on October 8, 2004).

"Frequently Asked Questions about Monkfish." Northeast Fisheries Science Center. http://www.nefsc.noaa.gov/read/popdy/monkfish/Survey2004/2004_index.html (accessed on October 10, 2004).

"Sargassum Anglerfish: Histrio histrio (Linnaeus, 1758)." Australian Museum Fish Site. http://www.amonline.net.au/fishes/fishfacts/fish/hhistrio.htm (accessed on October 10, 2004).