Sea Lamprey

• Scientific Classification of Sea Lamprey

Scientific classification

Kingdom: Animalia

Phylum: Chordata

Class: Hyperoartia (Petromyzontida)

Order: Petromyzontiformes

Family: Petromyzontidae

Genus: Petromyzon

Linnaeus, 1758

Species: P. marinus

Binomial name

Petromyzon marinus

Linnaeus, 1758

It is an eel-like fish that attaches with its suction-cup-like mouth to fishes, ,and feeds on their blood. Adults are tubular, mottled brown or black with a grayish belly, scaleless, and usually 12-20 inches long. Their mouth has teeth in concentric circles. Sea lampreys are native to the Atlantic Ocean, Lake Ontario, and the St. Lawrence River.

Lamprey has an anadromous life cycle which means they spend most of their lives at sea, but go to fresh water to spawn. When the mating season arrives - which runs from March to June on the species of P. marinus - adult lamprey will migrate in large quantities to the rivers. Not long after marriage, the female lamprey will release the eggs of up to 300,000 eggs into the basin at the bottom of the river that the male has made, and both die.

The eggs from the lampreys hatch into larvae that live in hiding in the pile of material at the bottom of the river for the next 3 to 5 years. During that period, the eye & mouth of the suction from the lamprey larva gradually evolved. After the two organs develop perfectly, the young lamprey fish will go to the sea or lake & start consuming the blood of other fish as its food. A lamprey of the P. marinus species is known to reach sexual maturity at 3 years of age & can reach a maximum size of 1 m.

Sea lampreys attach to fish with their suction cup mouth then dig their teeth into flesh for grip. Once securely attached, sea lampreys rasp through the fish’s scales and skin with their sharp tongue. Sea lampreys feed on the fish’s body fluids by secreting an enzyme that prevents blood from clotting, similar to how a leech feeds off its host.

In their native Atlantic Ocean, thanks to co-evolution with fish there, sea lampreys are parasites that typically do not kill their host. In the Great Lakes, where no such co-evolutionary link exists, sea lampreys act as predators, with each individual capable of killing up to 40 pounds (more than 20 kilograms) of fish over their 12-18 month feeding period.

Host fish in the Great Lakes are often unable to survive sea lamprey parasitism, either dying directly from an attack or from infections in the wound after an attack. Host fish that survive an attack often suffer from weight loss and a decline in health and condition.

Sea lampreys prey on most species of large Great Lakes fish such as lake trout, brown trout, lake sturgeon, lake whitefish, ciscoes, burbot, walleye, catfish, and Pacific salmonids including Chinook and coho salmon and rainbow trout/steelhead.

• Sea lampreys are jawless fish. They have large, reddish eyes and single nostril on the top of their head.
• Just like other fish, sea lamprey breathes using the gills. It has seven gill openings that are located behind the eyes.
• Sea lampreys are easily recognized by the large mouth, filled with circular rows of teeth. They are designed for sucking.
• Sea lamprey is feeding by sucking blood and bodily fluids of other fish. They will attach mouth to the prey like a vacuum cleaner. Sharp teeth and rasping tongue easily damages the prey's skin and induces blood flow.
• Larger fish might survive attack of sea lamprey, but smaller usually dies due to serious wounds or subsequent infections.
• Sea lamprey usually attacks white fish, trout and chub. Besides fish, sea lamprey feeds on small invertebrates.
• Sea lamprey also uses its mouth to attach itself to the stones and take a rest during migration from marine to fresh water.
• Sea lamprey spends around 10 years in the fresh water. After that time, it migrates to sea, where it stays usually around 2 years. During that time, sea lamprey will become mature and it will return back to fresh water for spawning.
• Spawning takes place in the spring. Sea lamprey can deposit as much as 100 000 eggs in the stony nests. Sea lampreys will die immediately after spawning.
• A lot of eggs deposited by sea lamprey serve as food for other fish in the water.
• Sea lamprey can induce significant damage to an ecosystem by killing large number of native fish species. For that reason, people use chemicals, electric fences and dams to prevent uncontrolled spreading of the sea lampreys toward sensitive rivers and lakes.
• Sea lampreys can be fished and used as delicacy in certain European countries.
• Average lifespan of sea lamprey is 14 years.

Sea lampreys have had an enormous, negative impact on the Great Lakes fishery, inflicting considerable damage. Before the sea lamprey invasion, Canada and the United States harvested about 15 million pounds of lake trout in the upper Great Lakes each year. By the late 1940s, sea lamprey populations had exploded. They fed on large numbers of lake trout, lake whitefish, and ciscoes—fish that were the mainstays of a thriving Great Lakes fishery. By the early 1960s, the catch had dropped dramatically, to approximately 300,000 pounds, about 2% of the previous average. During the time of highest sea lamprey abundance, up to 85% of fish that were not killed by sea lampreys were marked with sea lamprey attack wounds. The once thriving fisheries were devastated, and along with them, the hundreds of thousands of jobs related to the region’s economy.

Lamprey has long been consumed by residents of Europe & East Asia as food. In the era of Ancient Rome & the Middle Ages, lampreys were regarded as the food of the elite because it was often consumed by the nobles of the time. In addition to being eaten, another benefit of lampreys for humans is as the subject of brain research because the physical characteristics of lampreys seem primitive when compared with other vertebrate animals so that the nervous system of the brain & nerves of the lampreys is relatively simple.


Lamprey is not always regarded as a useful animal. In salmon farms, lampreys are considered as pests because they often attack & suck the blood from the fish that are kept. In North America, lampreys are also considered invasive species because they often attack local commercial fish without being controlled because of the absence of natural predators from lampreys there. One of the many attempts to suppress the populations of lampreys in North America is by wearing lamprisida, a kind of poison that is only lethal to lampreys.


source :

https://en.wikipedia.org/wiki/Sea_lamprey
http://www.dnr.state.mn.us/invasives/aquaticanimals/sealamprey/index.html
http://www.re-tawon.com/2012/10/lamprey-vampirnya-para-ikan.html
http://www.glfc.org/sea-lamprey.php


1.   How many years Sea Lamprey can live in the freshwater?
      a.  10 years
      b.  12 years
      c.   5 years
      d.  14 years

2.   What is genus of Sea Lamprey in scientific classification ?
      a.  Petromyzontidae
        b.   Petromyzontidae marinus
        c.   Petromyzontiformes
        d.   Petromyzon

3.  Sea lampreys act as predators, with each individual capable of killing up to....pounds
     a.  10
     b.  20
     c.  30

     d.  40

4.  When sea lamprey populations had exploded ?

     a.  1950s

     b.  1970s

     c.  1940s

     d.  1960s

5.  Sea lamprey breathes using the gills. How many gills?

     a.   Seven

     b.   Eight

     c.   Twentynine

     d.   Three