((Petromyzon marinusPetromyzon marinus))

Ms. Sneha SinghDepartment of Zoology,DAVCG, Yamunanagar.

External FeaturesExternal Features

Physical CharacteristicsPhysical Characteristics

They have no scalesThey have no scales

Adults can range from Adults can range from 5 to 40 inches long5 to 40 inches long

Rings of needle sharp Rings of needle sharp teeth form the teeth form the ““OO”” of of the mouth the mouth

HabitatHabitat Anadromous: Migrating Anadromous: Migrating

from salt water to from salt water to spawn in fresh water.spawn in fresh water.

In its natural habitat, the In its natural habitat, the sea lamprey lives in the sea lamprey lives in the open ocean. open ocean.

It migrates into It migrates into freshwater to spawn.freshwater to spawn.

Native HabitatNative Habitat

Sea lampreys are native to the coastal Sea lampreys are native to the coastal regions of both sides of:regions of both sides of:

North Atlantic Ocean, North Atlantic Ocean, Labrador Canada to the Gulf of MexicoLabrador Canada to the Gulf of Mexico Florida on one side Florida on one side Norway (Iceland and the Barents Sea) Norway (Iceland and the Barents Sea) Western Mediterranean Sea Western Mediterranean Sea Northern AfricaNorthern Africa

Some Prehistoric FactsSome Prehistoric Facts

Lampreys developed Lampreys developed from jawless fishes that from jawless fishes that swam through swam through prehistoric waters five prehistoric waters five hundred million years hundred million years ago.ago.

The jawless fish then The jawless fish then died in what later died in what later became a coal mine, became a coal mine, south of what later was south of what later was Chicago.Chicago.

ReproductionReproduction

In the spring and early summer, adult sea In the spring and early summer, adult sea lampreys ascend streams and rivers to spawn.lampreys ascend streams and rivers to spawn.

The males construct depressions that serves as The males construct depressions that serves as

nests or redds along sandy bottoms with gravel nests or redds along sandy bottoms with gravel or small stones.or small stones.

The female sea lamprey can lay from 30,000 The female sea lamprey can lay from 30,000 to100,000 eggs and the male fertilizes them to100,000 eggs and the male fertilizes them after which, both adults drift downstream and after which, both adults drift downstream and die. die.

Lamprey NestLamprey Nest

“Their nests, which are very conspicuous, look more like art than anything in the river. "

~Henry David Thoreau~

Lamprey Life CycleLamprey Life Cycle

Fortunately, only one year in the life of a sea lamprey is spent in Fortunately, only one year in the life of a sea lamprey is spent in parasitic feeding. They are unusual in having a complex life cycle, parasitic feeding. They are unusual in having a complex life cycle, whereas most fish have a simple life cycle.whereas most fish have a simple life cycle.

A. Sea lampreys go through an extended larval phase before metamorphosing into the bloodsucking parasitic phase. Each summer and fall there is one group of parasitic sea lampreys actively feeding in the Great Lakes.

B. The next spring, that group leaves the lake and migrates into tributary streams where they must build nests in clean gravel with flowing water.

C. Each female spawns an average of 60,000 to 70,000 eggs.

Life Cycle ContLife Cycle Cont’’dd D. After hatch, the larvae drift downstream to areas with slower

currents and sand/silt bottoms. There, they establish permanent burrows and enter a larval stage varying in duration from 3 to 10-ormore years.

E. Larvae lack eyes and the oral disc. Living concealed in their burrows, they are harmless and filter microscopic material from the water for food. When they reach lengths of 120 mm or more, some individuals begin metamorphosis in mid summer.

F. During metamorphosis they develop eyes, the oral disc, and changes in their kidneys that (in their native range) would allow them to enter the salt water of the Atlantic Ocean. That fall or the following spring, they instead enter the Great Lakes to feed parasitically on fish that summer and fall, and mature and spawn the next spring—completing their life cycle. Sea lampreys only spawn once and then die after spawning.

Life Cycle of the Sea LampreyLife Cycle of the Sea Lamprey• Average of 5-8 yearsAverage of 5-8 years• Eggs hatch and larvae Eggs hatch and larvae

feed at the bottom of feed at the bottom of streams and lakes on streams and lakes on debri and small plants debri and small plants (3-6 years)(3-6 years)

•   Turn into parasitic adult Turn into parasitic adult for 12-20 monthsfor 12-20 months

http://www.seagrant.umn.edu/ais/sealamprey_battle

Origins and Travel of the Sea LampreyOrigins and Travel of the Sea Lamprey

• Coastal areas of AtlanticCoastal areas of Atlantic• 1919 - canal built to bypass 1919 - canal built to bypass

N. Falls and allows accessN. Falls and allows access•   1921 - Lake Ontario for the 1921 - Lake Ontario for the

first timefirst time• 1936 - Lake Michigan 1936 - Lake Michigan • 1939 - invasion of all great 1939 - invasion of all great

lakeslakes• 1940-1950 Population 1940-1950 Population

explosionexplosion• 1955 - creation of the Great 1955 - creation of the Great

Lakes Fishery Commission Lakes Fishery Commission  http://dnr.wi.gov/org/caer/ce/eek/critter/invert/lamprey.htm

Improved Control Methods

Treatment with TFM is Treatment with TFM is currently still the currently still the primary tool for control.primary tool for control.

Ineffective and labor-Ineffective and labor-intensive screen weirs intensive screen weirs have been replaced have been replaced with low-head barriers with low-head barriers that block sea lampreys that block sea lampreys but allow jumping fish to but allow jumping fish to pass. pass.

Thank You…Thank You…