SECTION 19 



SEA LAMPREY ( PETROMYZON MARINUS LINNAEUS) IN THE 



SAINT LAWRENCE GREAT LAKES OF NORTH AMERICA: 



EFFECTS, CONTROL, RESULTS 



Carlos M. Fetterolf, Jr. 



The sea lamprey ( Petromyzon marinus Linnaeus 1758) is in the class 

 Agnatha, subclass Cyclostomata (Marsipobranchii ), order Petromyzontiforms 

 (Hyperoartia), and family Petromyzontidae. It is anadromous over most of 

 its range (Figure 1), spending its parasitic adult life in the sea, but is 

 landlocked in the Great Lakes and a few lakes in New York State. 



-ftf 



Figure 1. Range of the sea lamprey. Modified from Leim 

 and Scott (1966). 



Sea lampreys ascend freshwater tributaries and prefer a stony, gravelly 

 bottom for spawning (Figure 2). Adults excavate depressions about 15 cm 

 deep and 0.6-1 m in diameter in which the landlocked Great Lakes females 

 deposit about 50,000 - 70,000 eggs each. Adults die after spawning. Eggs 

 hatch into larvae (ammocetes), blind and toothless with a flexible, fleshy 

 hood overhanging the mouth. Ammocetes live 3-14 years as filter feeders in 

 burrows constructed in soft sediments of tributaries, 

 (metamorphosis) involves disappearance of the hood and 

 on the tongue and a buccal funnel with teeth radiating 

 from the mouth (Figure 3). Spawning Great Lakes sea lampreys are 30-60 cm 

 long. Ammocetes reach about 12-16 cm in length before transformation. 



Transformation 

 development of teeth 

 in all directions 



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