The Arctic Lamprey

──────────────────────────────────────────────────────────────────────────────────────
Arctic Lamprey
──────────────────────────────────────────────────────────────────────────────────────
Image of animal

──────────────────────────────────────────────────────────────────────────────────────
General Information;

Type: Fish
Diet: Omnivore
Size: 16.0cm
Weight: 200g
Conservation status:

Scientific Classification: Kingdom: Animalia, Phylum: Chordata, Subphylum: Vertebrata, Superclass: Agnatha, Class:Cephalaspidomorphi, Order: Petromyzontiformes, Family: Petromyzontidae. Subfamily: Lampetrinae, Genus: Lethenteron
Size relative to a 6-ft (2-m) man: not applicable
Arctic Lamprey Range


The most commonly occurring lamprey in Alaska; widely distributed. Overall abundance and trends unknown, but often found with some local abundance. Threats are minimal, although a commercial fishery for this species was initiated on the Lower Yukon River in 2003. Harvested for subsistence use although level of harvest is currently undocumented. Systematics needs study.
──────────────────────────────────────────────────────────────────────────────────────
Physical Features;
Body elongate and eel-like with two dorsal fins arising far back on the body (second with a dark blotch), and caudal fin connected to anal fin-like fold (well-developed in female, weakly developed in male). Brown to blue-black above, light brown, yellow or silver beneath. Seven gill openings on each side, mouth is jawless; a rounded oral sucker with teeth present on and around tongue. Body size and color are the most important distinguishing characteristics at the species level, but arrangement of teeth is most useful at the generic level; supraoral tooth bar with 2 large cusps, presence of posterial teeth, and sharp, well-developed tongue teeth.
──────────────────────────────────────────────────────────────────────────────────────
Mental Features;
During late spring, arctic lamprey migrate to fast-flowing stretches of clear streams to spawn. Spawning behaviour is dramatic: a group of 2 to 8 males and females carry stones and thrash their bodies in the gravel substrate to create a nest. Eggs and sperm are expelled into the long, shallow nest simultaneously. The male wraps his body around the female, using his sucker-like mouth as an anchor to her head. Females often spawn with more than one male during the breeding season. The eggs hatch within a few weeks and the resulting larvae burrow into the soft mud of the river bank. By autumn, the larvae have become smaller versions of their parents. The young of anadromous populations make their way towards the sea, while those of freshwater populations seek out deep, cold lakes.
──────────────────────────────────────────────────────────────────────────────────────
Diet;
Ammocoetes (blind larvae) filter-feed on microorganisms and fine debris. Plus, Adults of anadromous populations are parasitic, feeding on blood and flesh of fishes, whales, and sharks
──────────────────────────────────────────────────────────────────────────────────────
Habitat;
Arctic-boreal; Freshwater resident or anadromous; Pelagic at sea over continental shelf to bottom depth of 50 m (map shows marine distribution only); Not present in western Atlantic.
──────────────────────────────────────────────────────────────────────────────────────
Credits (c);

Images:
http://www.flickr.com/photos/lexup/4080746095/

Information:
http://www.arcodiv.org/Fish/Lethenteron_camtschaticum.html
http://www.polarlife.ca/Organisms/fish/fresh/lamprey/arcticlamprey.htm
http://2011.polarhusky.com/logistics/beringia/fauna/fish/arctic-lamprey/
http://www.adfg.alaska.gov/static/species/speciesinfo/_aknhp/Arctic_lamprey.pdf
http://en.wikipedia.org/wiki/Arctic_Lamprey
──────────────────────────────────────────────────────────────────────────────────────