Sea Lamprey

Events
2008 Lake Champlain Sea Lamprey Control Schedule
Sea Lamprey Trapping - April through June 2008
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Trapping and removing adult sea lamprey as they migrate up tributaries to spawn.
Lampricide Treatments - September/October 2008 - five
tributaries and two deltas are currently for lampricide treatments.
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Tributaries - Mt. Hope Brook, Mill Brook, and Great Chazy River in New York and
the Missiquoi River and Winooski River in Vermont
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Deltas - Saranac River Delta and Mill Brook Delta in New York
Select the SEA LAMPREY EVENTS link at the bottom of the page for more
information on these and other events related to sea lamprey control.
Biology
The sea lamprey (Petromyzon marinus) is one of four lamprey species found in the
Lake Champlain Basin. Lamprey are eel-shaped fish with a skeleton made of
cartilage and they belong to a relic (primitive) group of jawless fishes called
Agnathans. The sea lamprey has smooth, scaleless skin and two fins on its back
(dorsal fins). The sea lamprey is parasitic; it feeds on other fish, using a
suction disk mouth filled with small sharp, rasping teeth and a file-like
tongue. These are used by the sea lamprey to attach to a fish, puncture its
skin, and drain its body fluids.
Life cycle
Sea lamprey have a complex life cycle. The first four years of their life are
spent as ammocoetes [am-mah-seats] - a blind worm-like larval stage - in the
soft bottom and banks of waters that flow into Lake Champlain. They then
transform into the parasitic adult stage and enter the lake to feed on
landlocked Atlantic salmon (salmon), lake trout and many other fish species;
which they prefer due to their small scales and thin skin. After twelve (12) to
twenty (20) months in the lake the adults migrate back into the streams flowing
into the lake to spawn, after which the adults die.
Lampreys in Lake Champlain
Moderate numbers of sea lampreys were first noted in Lake Champlain in 1929. The
sea lamprey has been considered a non-native invasive species that entered Lake
Champlain during the 1800s through the Hudson/Champlain Canal. Recent genetic
studies indicate that the sea lamprey may be native to Lake Champlain.
Three other lamprey species are found in the Lake Champlain Basin. Two species
are non-parasitic, and while the third species is parasitic, it does not have a
significant impact on the Lake Champlain fish community.
Whether the sea lamprey is native to Lake Champlain or not, it is having
detrimental impacts on the Lake Champlain fisheries, ecosystem, and human
residents that are very significant.
Select the SEA LAMPREY BIOLOGY link at the bottom of the page for more
information on sea lamprey biology.
Impacts
Sea lamprey have a major detrimental impact on the Lake Champlain fish
community, the Lake Champlain Basin ecosystem, the anglers that fish Lake
Champlain, and the many people throughout the watershed whose livelihood is
directly or indirectly supported by the fishing and tourist industry.
Adult
sea lamprey attach to a host fish, rasp and puncture its skin, and drain its
body fluids, often killing the host fish. Their preferred hosts are salmon, lake
trout and other trout species, however they also feed on other fish species,
including lake whitefish, walleye, northern pike, burbot, and lake sturgeon. The
lake sturgeon is listed as a threatened species in New York and an endangered
species in Vermont and it is likely that sea lamprey are affecting their
survival.
Impacts on Host Fish
Most sea lamprey hosts are native fish species that have been part of the Lake
Champlain Basin ecosystem for thousands of years. Additionally many of these
fish species are important sportfish, highly prized and sought after by local
and visiting anglers.
Prior to any control measures, angler catches of lake trout and salmon in Lake
Champlain were a fraction of catches in similar lakes, despite intensive
stocking efforts. High wounding rates indicated that sea lamprey were having a
significant impact on the lake trout and salmon populations, and were preventing
the restoration of these native fish species to Lake Champlain.
Studies on the Great Lakes show a 40 to 60 percent
mortality rate for fish attacked by sea lamprey. Other studies found that a
single sea lamprey can kill 40 or more pounds of fish during its adult life. The
abundance of sea lamprey were obviously having significant impacts on Lake
Champlain's fishery and ecosystem.
Impacts on Local Economy
Poor fishing caused many anglers to seek fishing opportunities elsewhere. A
study estimated that 29.4 million dollars in economic benefits to businesses and
residents of the Lake Champlain Basin were lost due to the impacts of sea
lamprey.
Select the SEA LAMPREY IMPACTS link at the bottom of the page for more
information on the sea lamprey's impact on the fish and people in the Lake
Champlain Basin.
Control
Due to the severity of the impacts that sea lamprey
have on the Lake Champlain fishery and ecosystem, and the social and economic
impacts on the people who live in the Lake Champlain Basin, it has been
determined that sea lamprey populations should be controlled. The federal and
state governments, the agencies that manage Lake Champlain, the various
organizations that are concerned with Lake Champlain and the people that live in
the Lake Champlain Basin generally agree that it would be irresponsible not to
control the sea lamprey population.
The New York State Department of Environmental Conservation, the Vermont
Department of Fish and Wildlife and the United States Fish and Wildlife Service
formed a cooperative and began an integrated control program to reduce the sea
lamprey population in Lake Champlain to an acceptable level. The program is not
attempting to eliminate the sea lamprey from Lake Champlain, but rather to
reduce the impacts of sea lamprey on the lake's fishery and restore balance to
the ecosystem.
Control Efforts
Physical methods of control include the use of barriers to prevent adult sea
lamprey from migrating up waterways to spawn and traps to capture adult sea
lamprey before they can spawn.
However, the most significant and effective form of
control has been the treatment of tributaries and deltas with lampricides - TFM
in tributaries and Bayluscide on deltas. The lampricides target the larval sea
lamprey, killing them before they can transform into their parasitic adult form.
It should be noted that after years of study in Lake Champlain, the Great Lakes,
and other places where sea lamprey are controlled by using lampricides,
fisheries managers have concluded that the lampricides have little or no known
permanent effect on populations of non-target species present in the treatment
areas.
Control Program
Evaluation of an eight year experimental sea lamprey control program that took
place in Lake Champlain in the 1990s documented significant benefits for fish
and anglers. These benefits included decreases in wounding rates on trout and
salmon, increases in weight and survival rates of lake trout, increases in
angler catch rates of lake trout and a benefit to cost ratio of 3.5 to 1.
At the end of the eight year experimental sea lamprey control program, a
limited, three-year interim sea lamprey control program was undertaken from 1998
to 2000. After a thorough environmental review, a long term sea lamprey control
program began in 2002.
Fish sampling programs, salmon returns to fish ladders, angler surveys and
sampling of larval sea lamprey are used to measure the effectiveness of the
control program. The control program may be expanded to other streams and delta
areas if significant sea lamprey populations develop in them.
Assessments

Assessments of sea lamprey populations are made before any control measures are
undertaken and afterwards to assist in determining the effectiveness of the
controls. Field staff, using a variety of capture methods, sample both adult and
larval sea lamprey from streams and deltas to determine the presence and density
of sea lamprey populations. This information is used to determine which streams
or deltas are in need of control measures and which control measures to use.
Scientists and fish managers have considered, and continue to consider, other
methods to reduce sea lamprey impacts. These include the use of pheromones
(chemical attractants naturally produced by lamprey) to capture adult sea
lamprey, the release of sterile males to disrupt spawning, and the stocking of
lamprey-resistant strains of fish.
Select the SEA LAMPREY CONTROL link at the bottom of the page for more
information on sea lamprey control efforts in the Lake Champlain Basin.
More about Sea Lamprey:
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Sea Lamprey Biology - What
is a sea lamprey? How does it live and breed? How did it get into Lake
Champlain?
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Sea Lamprey Impacts -
Impacts from sea lamprey on the fishery and ecosystem of Lake Champlain
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Sea Lamprey Control -
Physical, chemical and other methods utilized in the effort to control sea
lamprey in Lake Champlain
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Sea Lamprey Events -
Schedule and announcements of treatments and other events related to sea lamprey
control on Lake Champlain
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Sea Lamprey Experts - Four
experts on Lake Champlain sea lamprey provide views on the natural history and
past, current, & future control efforts