Description | Habits | Management | Angling and Handling Tips

Rainbow Smelt Osmerus mordax
Osmerus mordax

Description

The rainbow smelt, a small fish eagerly pursued by anglers because of its fine flavor, is found along the coastal inshore areas of northeastern North America from Newfoundland to New Jersey, but is most abundant from the southern Canadian Maritime Provinces south to Massachusetts. Once exclusively an anadromous species (residing in saltwater, but entering freshwater to reproduce), the smelt has been successfully introduced into freshwater systems throughout the northeastern and central United States.

The rainbow smelt is slender, with a pointed head and a large mouth. This species can be distinguished from other small-bodied species along the Massachusetts coast by the presence of relatively large teeth, a deeply forked tail, and a small adipose fin. The smelt is mostly silver in color with various shiny hues along lateral line and a pale green dorsal surface.

Smelt length at age

AgeMales Length (inches)Females Length (inches)
15.65.6
27.47.8
38.28.6
49.39.6
59.59.8

Large smelt may reach 13 to 14 inches in length, but most adults do not exceed 7 to 9 inches, and 1 to 6 ounces in weight. Females are larger than males of identical age after their first year of life. The table to the left lists average lengths of adult fish in a population studied within the Parker River estuary of Massachusetts. Few smelt live beyond 5 years of age.

Both sexes become sexually mature at about 2 years of age, although some 1-year-olds may participate in spawning. Fecundity (number of eggs produced by a female per spawning season) ranges from 33,400 eggs for a 6 ½ inch fish to 75,600 for a 9 inch fish.

Habits

Smelt are a pelagic, schooling species that spends most of its time in nearshore waters. Their movement patterns are associated with seasonal changes in water temperatures. In summer, schools move to deeper, cooler, waters; in the fall they enter bays and estuaries where they actively feed until the onset of winter. During winter months, both adults and juveniles are found between estuary mouths and the brackish water areas of coastal streams. The spawning season in Massachusetts begins in late February south of Cape Cod and early March along Massachusetts Bay. The onset of spawning is influenced by an increase in water temperatures to about 40 to 42 degrees F, increasing day length, and the break-up of ice covering the water's surface at the spawning grounds.

To spawn, rainbow smelt move from estuaries into fresh or slightly brackish stream stretches where they release eggs and milt. Upstream movement to the spawning ground typically occurs during floor tides, and spawning occurs only at night. Adults move back downstream into resting areas in estuaries before sunrise. Most spawning occurs in fast flowing, turbulent water in stream sections dominated by rocks, boulders and aquatic vegetation. Fertilized eggs sink and adhere to each other and to any stationary material on the stream bottom. Eggs display the highest rates of survival when deposited in high velocity water, and on aquatic vegetation rather than bare rock substrates or sediment. Smelt eggs laid in low velocity areas suffer extremely high death rates due to siltation and possibly to inadequate amounts of dissolved oxygen.

Larvae are about ¼ inch long when they hatch and carry about a week supply of nutrition in a yolk sac. They move passively downstream in freshwater currents until reaching estuarine waters. By mid-summer, the juveniles reside in the deeper waters of estuaries, particularly during daylight hours.

Larvae and juveniles feed upon zooplankton, particularly microscopic crustaceans. Adult smelt feed primarily on small crustaceans and fish. In shoreline areas of Massachusetts Bay, smelt often key on sand and mysid shrimps. Smelt in turn are an important prey for a variety of predatory fish, including, striped bass, bluefish; and several bird and marine mammal species. Mortality due to predation is quite high for this species: up to 72% of adult fish die annually.

Management

Coastal smelt stocks throughout New England declined markedly by the 20th century, due to the construction of dams and to reduction in water quality. In some areas, after dams cut off traditional spawning grounds, eggs were deposited so densely in downstream sites that fungal infections caused massive egg mortality. High egg mortality also occurred due to siltation in watersheds experiencing extensive development. In 1874, the Massachusetts legislature initiated legislation to protect smelt in the Commonwealth. Starting about 1910, a widespread stocking program was established to restore smelt runs. Two methods were attempted. Specially constructed trays were placed in stream sites where extensive spawning was still occurring. After its surface was covered with developing eggs, each tray was transferred to streams that have been identified for smelt restoration. Transplanting was also attempted by stocking adult fish that were ready to spawn. These restoration efforts appeared to provide little or limited benefits to local stocks. Coastal smelt populations have not shown much improvement in recent decades, although specific watersheds produced occasional pulses of recruitment. Impediments to passage and the degradation of spawning habitat are thought to contribute to the ongoing poor status of local smelt populations.

Coastal stocks in Massachusetts are managed by the Division of Marine Fisheries, and inland ones by the Division of Fisheries and Wildlife. Management of coastal stocks in the 1980s included evaluation of environmental problems within watershed and regulation of the fisheries. Harvest was limited to hook-and-line fishing in most rivers, with dip-netting allowed in only one or two designated watersheds. Also, fishing was closed annually during the spawning season (closed March 15th through June 15th).

Angling and Handling Tips

Smelt offer an opportunity for action at the time of year when most anglers hang up their rods, store their gear, and warm the easy chair next to the fireplace. This species provides a hook-and-line autumn fishery in coastal areas, and a winter ice fishery in estuaries, river mouths, and riverine areas downstream from spawning sites. The smelt's attractiveness to anglers is certainly not because of its size - the length of most landed fish is 7 to 8 inches or less. However, what the smelt lacks in size, it makes up in numbers and taste. Once a school is located, anglers find the action fast-paced; catches of several dozen smelt are possible on a good day.

After ice forms in the winter, smelt begin to aggregate and move into coastal streams toward spawning grounds. Anglers wait for this smelt "run" with great anticipation. Some anglers build or rent smelt huts equipped with wood stoves for a comfortable approach to ice fishing while other hardy souls brave the weather. Conditions may be hazardous as well as uncomfortable, since ice is often unstable in areas of flowing water or areas where fresh and salt water mix. Schools of smelt tend to remain within localized areas for extended periods. Once a productive spot is found, it may remain productive for some time.

Many types of fishing gear are used, including cane poles, small ultra-light spinning outfits, and handlines. Baits such as sea worms, sand shrimp, and small local bait fish are fished on size #6 to #10 hooks, with a small sinker suitable to hold the bait in current. The depth at which bait is fished is critical to success. Baited hooks should be slowly moved up and down to assure they would pass through the schools of smelt. One secret to successful fishing is always to keep and eye on the line, no matter how interesting the conversation around you. Smelt produce such light taps or vibrations when grabbing baited hooks that rapt attention to the rod and line is a must.

Fresh smelt have a characteristic cucumber-like aroma. Cooked smelt have delicate, white meat and a fine, unique taste. Bones are soft and edible, although many prefer to remove the bones from cooked smelt before eating. Preparation for cooking often involves simply removing the head and entrails and even this is optional. Frying is an easy method for preparing smelt. Mix one cup of flour and one tablespoon of seafood or turkey seasoning in a plastic bag. Shake cleaned smelt in this mixture so that they are lightly dusted. Fry the fish in 1/8 -inch of vegetable or olive oil in a heavy skillet over medium heat. Fry for only for a few minutes each side. Drain the fish on paper towels and eat while still warm. Fried smelt are finger good, to be enjoyed plain, or dipped in tartar or seafood sauce. If you have eliminated fried food from your diet, broiling or baking are enjoyable alternatives.