Biology Lesson

Demersal, Pelagic, and Anadromous Fishes

CodCod Gadus morhua

A food fish of the cool water of the North Atlantic: Gadus morhua. The species that was the major attraction for European fishermen to come to America. The stock is now severely overfished with total collapse and closing of the famous cod fishing grounds off of Newfoundland., haddockHaddock

A North Atlantic food fish related to cod., halibutHalibut

A large flatfish or flounder sometimes weighing hundreds of pounds. The Atlantic halibut has been overfished to the point that it is endangered., and flounderFlounder

A flat fish that lies on the bottom camouflaged and ambushes its prey. It is characterized by having one of its eyes migrate to the top of the fish. Like many species, these have been overfished commercially so that the stock is perhaps 10% of what it was before industrial or modern fishing. are demersalDemersal fish

Bottom-dwelling fish. or ground fishGround fish Groundfish

Bottom-dwelling fish, especially commercially-valuable ones such as cod or flounder.—they live on or near the bottom of the ocean. Halibut and flounder are flat fish that look like long pancakes. As they mature, one eye moves from one side of the fish to the other, so that both eyes are on the top side. Flounder weigh only about one pound, but some halibut weigh six hundred pounds or more. Most commercial halibut today range from 5 to 100 pounds. Other demersal fish include pollockPollock

Pollock are the most active members of the cod family. They are deep, plump bodied fish that have three dorsal fins, two anal fins and a forked tail fin, with slightly projected lower jaw. Pollock average between 4 and 15 pounds in weight, although large ones can weigh to 35 pounds.
Read More, hakeHake

A term used for a family of cod-like fish. Most common in New England waters is the white hake., and ocean perchOcean perch Redfish

Ocean perch or acadian redfish are a bottom dwelling slow growing fish found generally in the deeper waters of the Gulf of Maine on rocky bottoms. The largest might be 15-20 inches long and 50 years old.The fish has the long dorsal fish and body shape of fresh water perches. Commercially it is caught in otter trawls and is overfished, and is used mostly as lobster bait., also known as redfish. They are sold as fresh fish and are also used to make frozen fish filletsFillet

In fishing, the narrow strip of boneless meat from either side of a fish's spine..

Other groundfish that are caught commercially in Maine include cusk, monkfish, plaice (or dab), and wolf fish.

PelagicPelagic

Fish living in the open ocean or seas rather than in waters adjacent to land or inland waters. fish live in mid-water depths or near the surface. Click here to view images of midwater fishing from PMM's photo collection. MackerelMackerel

Atlantic mackerel is the species found in the North Atlantic. A schooling, bony, oily, strongly-flavored food fish, green above with dark blue bars and silvery color below. The commercial stock has rebounded since near collapse in the 1970s. Without ice they spoil quickly. They are caught in purse seines which produce relatively little bycatch and no bottom damage. Today most of Maine's mackerel fishery is recreational. and herringHerring

Perhaps the world's most important food fish; there are sixteen species, with the Atlantic herring the dominent North Atlantic species. Fished heavily for centuries, today herring is caught in Maine waters primarily for lobster bait with some going to sardines. With new fishing technology there are serious concerns about overfishing. are pelagic fish that travel in large schoolsSchool

A large collection of fish that swim together, usually near the surface of the water, such as herring, mackerel, smelt, and menhaden. near the surface. Unlike the white-fleshed fish on the bottom, mackerel and herring are oily fish with darker flesh. Instead of salting and drying, these fish were preserved in salt brineSalt brine

Highly salted water.. Mackerel is often canned, and herring may be canned as sardinesSardines

Small herring, preserved in oil or sauces and canned. Maine had many sardine factories.. In the 19th and early 20th centuries people ate mackerel canned, salted, and fresh. Mackerel- fishing Mainers followed the schools of fish from Cape Cod to the Gulf of Maine. Now mackerel is far less popular and is not fished commercially in Maine. Both mackerel and herring are used as bait, because their strong smell attracts other fish and lobstersLobster Homarus americanus

An edible crustacean, Homarus americanus refers to the species found in the North Atlantic.. Herring was smoked, salted, canned and eaten fresh. Canned herring (sardines) provided hundreds of jobs for fishermen and fish processors into the 1950s. Changing American tastes and a growing preference for tuna collapsed the canned sardine market. The last cannery in Maine closed in 2010. Herring is in high demand as lobster bait. The fishery has virtually discarded traditional seining or waiting for the herring to come to weirs or traps. Herring are now pursued actively by midwater trawlers, where one or two vessels tow a massive net. Trawling in areas closed to groundfishing has made this controversial, as has the decline in inshore juvenile herring populations. Click here to view images of the herring fishery from PMM's photo collection. In the late nineteenth century, menhadenMenhaden Pogy, Mossbunker

One of the herring family, menhaden are one of the most important food fishes on the Atlantic Coast. Maine is at the northern limits of their range. They are caught in purse seines and have been traditionally processed for fertilizer and oil especially in the Chesapeake and North Carolina areas. were also caught on the Maine coast and used for fertilizer and fish oil. Large pelagic fish include tunaTuna

Fast swimming migratory ocean fish of tremendous commercial importance. Capture is now regulated by the National Marine Fisheries Service. Appear in the Gulf of Maine in summer where there is a recreational fishery., swordfishSwordfish

A large, warm water, highly migratory ocean traveling fish characterized by its sword. A summer visitor to the banks off the Maine coast. While the largest caught have been 1000 pounds, those that visit the Gulf of Maine are in the 50-60 pound range. Commercially the fish are caught on longlines or harpooned. With such a wide-ranging fish, fisheries regulation is difficult. It is considered to be overfished but recovering., and sharkShark

Relatively few sharks are found in Maine waters, with the 3-4 foot dogfish the common species. Offshore in summer are found blue sharks in the 12 foot range. Other species are uncommon. With the passage of the Shark Finning Prohibition Act of 2000, catching sharks for their fins for shark-fin soup in US waters has been prohibited. However, that is a serious threat to shark species in other waters. .

Anadromous fishAnadromous fish

Fish that seasonally leave the sea to swim up-river to spawn in fresh water; examples include alewives, smelts, shad, salmon, striped bass, bluebacks, and sturgeon. spend most of their lives in salt water, but swim up rivers to spawnSpawn

The eggs of fish, or, as a verb, the laying of eggs by fish. in fresh water. Maine anadromous fish are salmonSalmon

A marine and freshwater food fish, inhabiting North Atlantic waters near the mouths of large rivers. Salmon are anadromous fish, entering rivers to spawn (lay eggs.) In Maine, salmon fishing was once a commercial, then a sport fishery; now wild salmon are an endangered species. Many are farm-raised., shadShad

American or atlantic shad are an anadromous fish traditionally caught in weirs or set nets along the Eastern Seaboard. They are the largest member of the herring family, and are often found in nets together with salmon. Damming rivers destroyed the shad fishery, as egg-bearing shad cannot jump, so do not use ladders put in for alewives and salmon. In Maine this is only a recreational fishery., alewivesAlewives

Anadromous fish of the herring family about 12 inches long. Fished commercially in the spring when they run upriver to spawn. Catch is now a third of what it was in the 1970s. Offshore they are caught by midwater trawlers. Once smoked and pickled, now mostly used as lobster bait., and troutTrout

One of the salmon family, it is chiefly a fresh water fish with several species. Some can be anadromous and found in salt water.. These are preserved best smoked, but historically were not preserved for long periods like cod and mackerel. Alewives are a popular bait fish for lobstering.

Salmon were extremely abundant in colonial times and were a popular fresh fish, in addition to being salted or canned. Fresh salmon is popular today as a result of the availability of fast, refrigerated transport. Eastern Maine and New Brunswick have many salmon aquacultureAquaculture

Growing fish or shellfish in a controlled environment at sea or in tanks or lagoons on land. Fish grown in such an environment are said to be farm-raised. pens.

Shellfish

ShellfishShellfish shellfish

Common name for marine invertebrates: crustaceans such as lobsters, mollusks such as clams, echinoderms such as sea urchins. is a general term including mollusksMollusk

A soft bodied invertebrate animal often with one or two hard shells. Familiar mollusks are shell fish, squid and octopus, and sea slugs, snails and limpets. and crustaceansCrustacean crustacea

Lobsters, shrimp and crabs all belong to the subphylum of arthropods called crustacea. They have a hard exoskeleton which is shed as the animal grows.. Mollusks are clamsClam

A shelled mollusk of which there are a number of species. It has a relatively symmetrical oval shell. The dominant Maine clams are soft shelled and live in the mud in the intertidal zone., musselsMussel

A bivalve mollusk with numbers of species found in both fresh and salt water. Of commercial interest in Maine is the blue mussel, found in natural mussel beds and raised in aquaculture., scallopsScallop

Sea scallops are bivalve mollusks which differ from clams and mussels by being active free swimmers. They have symmetric fluted shells. They are caught with dredges. Maine's fishery became commercially viable around 1900 with the introduction of the gasoline engine., and oystersOyster

Oysters are a bivalve mollusk of great commercial value. Disease and overfishing have decimated once thriving beds in the Chesapeake Bay, New York Harbor and Long Island Sound. Maine's waters have never had a commercial oyster fishery due to slow growth compared to areas south of Cape Cod. There are some oyster farms that are now seeking to provide oyster brood stock.. Crustaceans include crabsCrab Rock crab, Green Crab

Crabs are often found in lobster traps. The Rock Crab is Maine's native crab, up to 6 inches shell size while the smaller Green Crab is an invasive Northern European species which had spread all along the Maine coast by 1953.
Read More, shrimpShrimp

A small swimming crustacean, typically caught commercially by trawling. Maine's shrimp are northern shrimp, and the Gulf of Maine is at the southern limit of their range. The fishery is a winter fishery which began in the 1930s., and lobsters.

Clams are dug from Maine’s beaches, and were once used as bait for cod. Like clams, mussels have been used for both food and bait. They inhabit intertidal zonesIntertidal zone

The land exposed between high and low tides. in rocky areas. MusselsMussel

A bivalve mollusk with numbers of species found in both fresh and salt water. Of commercial interest in Maine is the blue mussel, found in natural mussel beds and raised in aquaculture. have grown in popularity since the advent of mussel aquacultureAquaculture

Growing fish or shellfish in a controlled environment at sea or in tanks or lagoons on land. Fish grown in such an environment are said to be farm-raised.. ShellfishShellfish shellfish

Common name for marine invertebrates: crustaceans such as lobsters, mollusks such as clams, echinoderms such as sea urchins. are sometimes farm-raisedAquaculture

Growing fish or shellfish in a controlled environment at sea or in tanks or lagoons on land. Fish grown in such an environment are said to be farm-raised. on the Maine coast. Sea scallopsScallop

Sea scallops are bivalve mollusks which differ from clams and mussels by being active free swimmers. They have symmetric fluted shells. They are caught with dredges. Maine's fishery became commercially viable around 1900 with the introduction of the gasoline engine. have large delicious meats that bring high prices. They are caught with a special metal-ringed net dragged along the bottom behind a fishing boat, or else by scuba divers. Dredging for scallops is tightly regulated in an attempt to preserve the fishery. These shellfish feed by filtering water; poisonous planktonPlankton

Microscopic organisms that float freely in the ocean. Plankton is made up of both plants (phytoplankton) and animals (zooplankton). blooms called red tidesRed tide

Red tides are harmful algae blooms, when phytoplankton grow quickly and are visible. Some of these phytoplankton are toxic and can kill animals that eat them. Shell fish beds are especially vulnerable as shell fish feed by filtering water, which concentrates the toxins, although the shell fish themselves are not harmed. Red tides will close areas to shell fishing.  and poor water quality can close the fishery.

Shrimp are most plentiful during the winter when they carry their eggs. Maine shrimp, or northern shrimp, are smaller than southern shrimp, growing only to about 4-5 inches in 5 years. Crabs caught in Maine are rock crabs. Picking crabmeat is time-consuming, making them less popular than lobsters. Crabs are usually caught in lobster traps as bycatchBycatch

Marine organisms that are caught unintentionally when fishing, usually by towed nets. A bycatch can be very large and is usually discarded, something that is now being seen as wasteful and ecologically damaging..

Today, lobsters are the most valuable fishery in Maine, second only to herring in tons of fish landed.

Click here to see images of shellfish harvesting from PMM's photo collection.

Marine Mammals

Harbor porpoises, harbor seals, fin whales, minke whales, humpback whales and, rarely, right whales live along the Maine coast. Right whales historically provided blubberBlubber

The layer of fat found under the skin of marine mammals like whales, porpoises and seals. It stores energy and serves as an insulator. Heated, it can be rendered or melted into oil. for oil, and harbor seals were sometimes hunted for their furs. Today all marine mammals are protected by the Federal Government and may not be hunted or disturbed.

Other Marine Creatures

Two echinodermsEchinoderm

Marine animals that exhibit five armed or part radial symmetry. In Maine they are most commonly seen as sea stars, sea urchins, and sea cucumbers., sea urchinsSea urchin

Echinoderm with a spine covered shell; feeds on algae. Roe is prized as a delicacy in the Far East. In 1987, a market for Maine sea urchins was developed in Japan triggering a sea urchin rush that severely depleted the resource. It is now tightly controlled but it is difficult to reestablish. and sea cucumbersBeche-de-mer sea cucumber, trepang

Beche-de-mer (sea cucumbers) are sea-dwelling echinoderms similar to sea stars and sea urchins. In Asia, where they are considered a delicacy, they are dried and pulverized and used in foods. Sea cucumbers contain chondroitin, thought to help joint pain and stiffness from arthritis. They are in demand for health supplements, although there is no documented proof of effectiveness. The sea cucumber grows slowly, raising concerns about management of their harvest. Commercially, it is also known as trepang., are now fished in Maine. Sea cucumbers, also known as beche-de-merBeche-de-mer sea cucumber, trepang

Beche-de-mer (sea cucumbers) are sea-dwelling echinoderms similar to sea stars and sea urchins. In Asia, where they are considered a delicacy, they are dried and pulverized and used in foods. Sea cucumbers contain chondroitin, thought to help joint pain and stiffness from arthritis. They are in demand for health supplements, although there is no documented proof of effectiveness. The sea cucumber grows slowly, raising concerns about management of their harvest. Commercially, it is also known as trepang., were a delicacy in nineteenth-century ChinaChina

During the period of the China Trade, when Mainers were sailing to ports in China, the Qing (or Ch'ing) Dynasty (1644-1911) was in power. The Qing Dynasty was established by the Manchus in northeastern China, and expanded to surrounding territories of Inner Asia, establishing the Empire of the Great Qing.
Read More and were harvested from Pacific islands. Today, they are processed in Stonington, Maine, for the pharmaceutical chondroitinChondroitin

A chemical compound believed to be useful in the treatment of osteoarthritis. as well as for export as food. Sea urchin roeRoe

Eggs of a fish, or egg mass of crustaceans such as lobster. is popular in Japan. ElversElvers

Young eels returning to fresh water where they will live as adults before going to sea again to spawn., or baby eels, are also considered a delicacy in the Far East, and eels are fished for use as bait.

For more information on Maine and Northeast Atlantic fish, see the Maine Department of Marine Resources web page on species Information.