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American Smelt
There are few fisheries where catches have shifted so dramatically
from one part of the country to another as that of the American
smelt.
Prior to 1948 the commercial smelt fishery was centered on the
Atlantic coast. In that year an experimental gillnet fishery was
established in the Great Lakes, and became increasingly successful.
Gradually, the Great Lakes fishery exceeded the Atlantic coast
ventures both in terms of the weight of total landings and their
market value.
There is also an extensive sport fishery of smelt in the Great
Lakes and Maritimes. Fishermen use hooks, lines, nets and spears
as gear, and fishing is carried out all year. Ice fishing of smelt
is popular and in several small New Brunswick lakes, for example,
landlocked smelt populations are fished exclusively by hook and
line through holes in the ice.
Populations of the American or rainbow smelt are widely distributed
throughout eastern and western North America, inhabiting coastal
waters as well as countless inland freshwater lakes. On the Atlantic
coast they are found from New Jersey in the south to Hamilton
Inlet, Labrador in the north. Their inland habitats include lakes
in New Hampshire, Maine, the Maritimes, Newfoundland, Labrador,
Quebec and eastern Ontario. On the Pacific coast, smelt are found
from Vancouver Island northward around Alaska and eastward along
the Arctic coast at least as far as the Mackenzie River. The same
species also ranges westward along the Arctic coast of the USSR
as far as the White Sea.
In 1906, smelt stocking was begun in streams and lakes feeding
Lake Michigan in order to provide forage for salmonids. Eventually
large smelt populations were found in all the Great Lakes, especially
Lake Erie. There is some evidence that the smelt inhabiting Lake
Ontario were not a result of these stockings but of an independent
movement from Lake Champlain stocks. Smelt have also been introduced
into smaller lakes in central Ontario.
Topics presented in this document :
The scientific name of the American or rainbow smelt is Osmerus
mordax. It belongs to the family Osmeridae, which also
includes the longfin smelt and the eulachon of the west coast,
the pond smelt of the western Arctic, and the capelin which inhabits
east coast waters. Relatives of the American smelt include the
Atlantic argentine, the salmonids, and, although dissimilar in
appearance, the European smelt. While the Atlantic silverside,
found along the Maritimes coast, is similar in appearance to both
the American smelt and capelin, it is altogether unrelated.
The American smelt is a pelagic schooling species, inhabiting
inshore coastal regions and the midwaters of lakes. Since it is
sensitive to both light and warmer temperatures, schools of smelt
tend to concentrate near the bottom of lakes and coastal waters
during daylight hours.
In appearance, the American smelt is a slender, silver fish, with
a pale green or olive-green back. Fresh from the water, the sides
of the fish take on a purple, blue or pink iridescent hue. Most
specimens are less than 20 cm long, although some measuring 35
cm have been found. The scales on the smelt are large and easily
detached, and at spawning time those on the males develop small
tubercles, resembling tiny buttons which serve as a mark of their
sex. The lower jaw of the fish projects beyond the upper one and
the entire mouth extends beyond the middle of the eye. On the
tip of the tongue are large teeth. One large dorsal fin is located
about halfway along the back and, behind that, a small adipose
fin.
 Distribution and Migration
The Osmeridae family, as well as the related Salmonidae
family, include a number of "anadromous" species
which pass part of the year in salt water, migrating to fresh
or brackish water to spawn. Both the American smelt and the Atlantic
salmon are among those species which are often able to adapt to
a strictly freshwater environment.
In the spring, both anadromous and landlocked adult smelt migrate
upstream to freshwater spawning grounds. During bad weather, however,
or where obstructions along the migratory route inhibit movement,
some spawning may occur before freshwater sites are reached. Stormy
weather may also cause spawning to take place along beaches or
on gravelly-bottomed offshore banks. Smelt in the Miramichi River
system, for example, begin their upstream migration before the
spring thaw has begun. When the ice breakup begins, freshets can
temporarily halt upstream migration, and, in some instances, force
the smelt to move back downstream. If the migration is sufficiently
delayed spawning may take place below the head of the tide.
Spawners reach the tide head in the main tributaries when the
water temperature is only 4°C to 5°C. In the Great Lakes,
however, migration begins shortly after the ice breaks up, when
the water temperature is at least 8°C. Smaller streams are
entered when the temperature is 6°C to 7°C. Anadromous
smelt in the Gaspé Peninsula spawn in similar temperatures,
although some landlocked populations in Lake Champlain and lakes
in New Hampshire may spawn in temperatures as low as 2°C.
Once the freshwater site has been reached, the smelt remain there
spawning for a number of days. At any given age, the larger smelt
spawn first. This applies to the entire migrating population,
so that the average size of smelt on the spawning grounds decreases
as the season advances. Shortly after spawning many of the males
die.
 In the Miramichi system, where stocks have been more intensively
studied than other Canadian stocks, the surviving males and females
are known to remain in the streams for about five to 10 days before
migrating downstream. They remain in the Miramichi Bay for the
summer; in early October they begin to reappear in the estuary
and, in late November, when the ice forms,
they settle in the lower estuary and inner bay for the winter.
Studies carried out through a system of tagging indicate that
most smelt spawning in the Miramichi return to the same stream
or to one nearby. Very little intermixing of fish has been observed
between main branches of the River system or between early and
late-run streams. It has been shown, therefore, that the smelt
demonstrate a degree of homing.
Observations in Lake Superior show that some smelt are mature
at two years of age, and therefore able to spawn, and all are
mature at three years of age. In the Miramichi River system, studies
have shown that 66 per cent of spawners were two years old, 30
per cent were three years old, and four per cent were four, five
or six years old.
Fecundity, or the number of eggs produced per female, varies from
one area to another. Anadromous populations are more fecund than
landlocked populations. For example, a fully grown (about 21 cm
long) female smelt from the Miramichi River will produce about
70,000 eggs, while a female of a similar length from Lake Superior
will produce about 31,000 eggs . The smallest mature female observed
in the Miramichi (about 10 cm long) produced an average of about
7,000 eggs.
Observations of smelt in the Miramichi indicate that spawning
occurs mainly at night, typically over a gravelly bottom. Females,
in fact, sometimes leave the spawning site during the daylight
hours. During spawning, two or more males place themselves alongside
a female and release their milt at the same time the female releases
a cluster of eggs.
On contact with water the outer envelope of the egg becomes sticky
and adheres to the gravel or other bottom objects. This outer
coat is soon broken and torn away by the current except for that
portion of the egg adhering to the bottom surface. Where the density
of egg deposits is not too high, this little "stem"
permits the egg to sway freely in the current, thus assuring good
aeration. In some streams, however, where smelt are obliged to
spawn below impassable obstructions, repeated spawnings will result
in egg deposits of up to 10 cm thick. Water circulation and aeration
of the lower layers is very poor, due to the buildup of sediment,
and mortalities are extremely high.
Experiments carried out on a Miramichi tributary indicate that
at low egg densities about four per cent of the eggs hatched,
while at very high densities only 0.03 per cent of the eggs survived.
Egg mortality is also high when freshets occur, causing streams
to overflow their banks. Under these conditions many smelt spawn
beyond the normal limits of the streambed. These eggs die when
the streams return to their original size.
The time required for the eggs to hatch depends upon the water
temperature. At 4°C, eggs take at least 50 days to develop;
at 6°C hatching occurs after about 30 days, and at 10°C,
less than 20 days is required.
Larvae are about 5 mm long at the time of hatching. They drift
downstream with the current to the estuary where they drift back
and forth with the tide. There is evidence that they are able
to exercise some control over their movements, since daylight
finds them close to the river bottom.
During the summer months, larvae and juveniles are found throughout
the Miramichi River, Bay, and Estuary, then leave the river in
mid-August.
Female smelt grow more quickly than males, attain a larger size,
and live longer. In the Miramichi River, two year-old females
were observed to be 13.9 cm long on the average; two year-old
males were 13.5 cm long. By five years of age, females were 20.6
cm long and males were 18.3 cm long. Lake Superior smelt are apparently
larger throughout their adult life than Miramichi smelt. Two-year-old
males and females averaged about 15 cm in length, whereas five-year-old
males averaged 21.8 cm and females averaged 23.9 cm. Smelt restricted
to small inland lakes are usually much smaller and often do not
exceed 10 cm in length. Individuals 36 cm long have been captured
in the coastal waters of the Maritimes and in Lake Ontario.
In the Great Lakes, a shrimp-like crustacean, Mysis relicta,
is the smelt's principal food. Smelt also consume other zooplankton,
insect larvae, and aquatic worms and may eat small quantities
of fish, including smaller smelts, sculpins, burbots, white bass,
whitefish, and emerald shiners. Studies of Miramichi River populations
show that smelt larvae consume small zooplankton, while adults
consume larger zooplankton, including shrimps and shrimplike organisms,
aquatic worms, and small fish, such as juvenile herring, mummichog
and silversides.
Conversely, Miramichi smelt are prey for cod, salmon, seals, comorant,
and mergansers, while Great Lakes smelt fall prey to lake trout,
salmon, brook trout, burbots, walleye, yellow perch, and birds
such as gulls and crows.
Smelt are also afflicted by parasites, one of which forms white
cysts in the viscera and body cavity of smelt inhabiting both
North American and European waters. Fortunately, it does not appear
to be harmful to humans who consume the fish. Smelt may also fall
victim to contagious diseases. Between 1942 and 1946, an estimated
50 million pounds of smelt in Lake Michigan were lost because
of what may have been a viral infection.
 On the Atlantic coast, anadromous smelt stocks are fished during
the fall and winter before the onset of the migration to spawning
sites. Commercial-sized smelt are caught in gillnets of
about 3.25 cm mesh size. Bag nets of a smaller mesh size are also
used to avoid gilling and to ensure that smelt are trapped in
the net "bag" . The opening of a bag net may be up to
10.5 m wide and 7.5 m long, and the bag is oriented so that the
large "mouth" faces the tidal currents. The whole structure
is held in place by poles driven into the bottom of the estuary
or bay. As smelt move with the current, they enter the large opening,
continue through the smaller opening of the internal trap, and
finally arrive at the "bunt", the tapered end of the
bag net. At slack tide, the fisherman hauls up the foot line to
shut off the mouth of the net, shakes all the smelt back towards
the bunt, and hauls it out of the water, emptying the catch into
his boat.
The bulk of Atlantic coast smelt are caught during the winter
through holes made in the ice. The most popular gear is the "double-ender"
box net. A mesh leader about 6.5 m wide and 30 m long is placed
across the current. At the end nearest the centre of the channel,
the leader passes through the entrance into a long rectangular,
small-mesh "box". At both ebb and flow tides, smelt,
arriving at the leader, pass along it until they end up in the
trap inside the box. The design is such that, even if the tide
changes, escape is impossible. The centre of the box net is directly
under the rectangular hole made in the ice, so that the fisherman
may easily haul the bunts at either end of the box onto the ice.
 In the Great Lakes, smelt are fished
commercially by trawls which are towed through the schools of
fish. This mobile gear permits much higher catch rates than can
be obtained with the fixed gear used in the Atlantic coast smelt
fishery, and also makes possible a year-round fishery.
The smelt is also a popular sport fish. In Lake Erie, thousands
of fishermen use dip nets and seines to capture smelt. In the
Maritimes, smelts are fished with hook and line from docks during
the summer months. Dip nets are limited by regulation to use during
the spring. In the winter, thousands of small shacks are erected
throughout the Maritimes and Quebec for purposes of ice fishing.
Sports fishermen use a hook and line or spears.
Before 1948, about 99 per cent of Canadian commercial landings
came from the Atlantic coast; the remainder came from British
Columbia. Total east coast landings numbered about 3,700 metric
tons (t) per year, with New Brunswick accounting for about 70
per cent of the total. About half of New Brunswick landings came
from the Miramichi River system. In 1948, an experimental gillnet
fishery for smelts was undertaken in the Great Lakes which, following
the conversion to trap nets, saw landings increase rapidly to
2,086 t by 1958. The conversion to mobile gear in the following
year led to new increases, and Great Lakes landings reached 8,662
t in 1962. A record of 12,399 t was attained in 1978. In 1979,
Great Lakes landings totalling 10,979 t were valued at $2,035,000.
Atlantic coast (reported) landings were 2,542 t and valued at
$1,065,767. It is highly likely, however, that total landings
were much higher. Landings in both major fisheries seem to be
determined more by market demand than by the availability of the
smelt resource.
During the 1950s, the abundant new supply of smelt from the Great
Lakes caused a general decline in prices paid to fishermen. With
the introduction of trawls which permitted larger catches per
vessel per day, prices again fell drastically in the early 1960s.
On the Miramichi River, for example, prices often exceeded 90
cents per kg in the late 1940s and early 1950s; by the early 1960s,
they were below 45 cents per kg. Not surprisingly, the number
of Miramichi smelt fishermen decreased steadily throughout the
1950s, and then dropped drastically in 1960. Atlantic coast landings
reached a low of 1,169 t in 1962.
 A considerably higher price is paid for anadromous smelt, however,
and reflects the opinion that they are of superior quality than
the landlocked variety. In 1962, for example, the average price
paid for smelt on the Atlantic coast was almost 42 cents per kg,
whereas only 15.3 cents per kg was paid for those landed in the
Great Lakes . In 1979, when Atlantic coast fishermen received
an average of 85.5 cents per kg, Great Lakes fishermen received
37.8 cents per kg.
For many east coast fishermen, the smelt fishery is an "off-season"
activity and year-to-year variations in participation will therefore
be influenced by their economic success in other fisheries.
 Most of Canada' s smelt production is exported frozen
to Japan or the United States. Some Great Lakes. smelt is sold
fresh to the United States. In 1982, Canada exported an estimated
13,500 t of smelt products, valued at close to $ 17 million .
Management regulations for the smelt fishery vary from province
to province and include restrictions on the location and type
of gear used, mesh size and the establishment of seasons. However,
comprehensive management plans for the smelt fisheries do not
exist and considerable research is necessary before a scientific
management plan could be instituted. In general, estimates of
population size and exploitation rates are difficult to calculate
accurately; growth rate and natural mortality rate for given populations
are unknown. Until estimates of these parameters become available,
it is impossible to recommend a scientifically acceptable catch
level. A management plan might be concerned with measures which
would exert more control over the level of fishing effort and
the setting of a maximum annual catch limit. One objective of
a management plan might be to assure the highest possible yield
from the stocks without endangering the existing smelt populations.
Others might be to produce the optimum economic benefits to fishermen
or to achieve an equitable distribution of benefits.
Market research is also necessary, involving both the industry
and the consumer. Answers to questions such as the price that
can be expected for finished products, and whether processors
and fishermen on the Atlantic coast are interested in investing
in an expanded smelt fishery would provide important data. The
industry could then investigate the possibilities of developing
fishing efforts and the processing industry, and the feasibility
of expanding markets.
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