Sea+Lamprey+-+Laque

= Sea Lamprey //(Petromyzon Marinus)//    =

__General Information:__
Sea Lampreys are similar in shape to eels and have a soft, cartilaginous skeleton. They average in size at 2 to 2 ½ ft long and can reach a maximum of about 3ft. Sea Lampreys tend to weigh about eight to thirteen ounces. Sea Lampreys could vary in shades but are usually blackish blue, silver, or lead colored.(1) Sea Lampreys are jawless fish with a tooth studded oral disk. They use the oral disc like a suction cup to attach to the side of a host fish.(2)

__Detailed Description:__
//**Life Cycle/Reproduction:**// Only one year in the life of a sea lamprey is spent in parasitic feeding. Unlike most fish, who have a simple life cycle sea lampreys’ life cycles are very complex. Sea Lampreys go through an extended larval phase before metamorphosing into the parasitic phase. During spring adult lampreys migrate to streams to build nests. Females spawn an average of sixty to seventy thousand eggs. The larval stage lasts over three years. During this stage sea lamprey are harmless and feed by organic filtering. Some begin metamorphosis in mid summer. They develop oral disks and start to feed parasitically the following summer and fall. Lampreys then mature and spawn the next spring which completes their life cycle, since they only spawn once and then die after spawning.(3) Sea Lampreys are parasitic and feed on a large variety of fishes and marine mammals. Once attached, the lamprey opens wounds on the prey's skin.(4)  They use their teeth to scrape away the skin of their host and suck out its blood and body fluids. The sea lamprey also produces an anticoagulant in its saliva, which prevents the prey’s blood from clotting.(5)  __**Habitat and Distribution:** __ Sea lamprey larvae tend to live in muddy or sandy freshwater streams but mature sea lampreys live in open sea or lake water and return to freshwater streams to spawn. In general sea lampreys live on both sides of the North Atlantic Ocean, in the western Mediterranean Sea, and in the Great Lakes of North America.(6)  __**Impacts:**  __ **//Ecological://** Each sea lamprey can destroy up to 40 or more pounds of fish in its lifetime because of this there is a decline of native fish in the Great Lakes due in part to the introduction of the sea lamprey.(7) **//Human://** At the height of the sea lamprey population, recreational and commercial fishing activities have been reduced. Methods used to lessen the lamprey population are also an economic drain. A large amount of money also continues to be spent in restoring the sport fish populations that have been damaged by sea lampreys.(8)  The sea lamprey was first discovered in Lake Ontario in 1835, Lake Erie in 1921, Lake Huron 1932, Lake Michigan 1936, and Lake Superior 1946.(9) Upgrades to the Welland Canal, which joins Lake Ontario to Lake Erie bypassing Niagara Falls, provided a way for lampreys to invade Lake Erie in 1919.(10)  
 * // Diet: //**
 * __History:__**

 __**Control Measures:**__ The sea lamprey is one of the few aquatic invasive species that is being successfully controlled. Sea lamprey populations in the Great Lakes are currently kept in check through aggressive control using several methods, including lampercide application, barrier installation, sterile-male release, and trapping.(11)

__ __ (1) http://www.gma.org/fogm/petromyzon_marinus.htm (2)http://www.glsc.usgs.gov/main.php?content=research_lamprey&title=Invasive%20Fish0&menu=research_invasive_fish (3)http://www.glsc.usgs.gov/main.php?content=research_lamprey&title=Invasive%20Fish0&menu=research_invasive_fish (4)http://www.fisheries.vims.edu/lamprey.htm (5)http://www.in.gov/dnr/files/SEA_LAMPREY1.pdf (6)http://animals.jrank.org/pages/1947/Lampreys-Cephalaspidomorphi-SEA-LAMPREY-Petromyzon-marinus-SPECIES-ACCOUNT.html (7)http://www.in.gov/dnr/files/SEA_LAMPREY1.pdf (8)http://www.in.gov/dnr/files/SEA_LAMPREY1.pdf (9)http://www.sgnis.org/www/lamprey.htm (10)http://www.in.gov/dnr/files/SEA_LAMPREY1.pdf (11)http://dnr.wi.gov/invasives/fact/lamprey.htm