Paddlefish

Description

American paddlefish are among the largest and longest-lived freshwater fishes in North America.They have a shark-like body,average 1.5 m (4.9 ft) in length,weigh 27 kg (60 lb),and can live in excess of thirty years.For most populations the median age is five to eight years and the maximum age is fourteen to eighteen years.The age of American paddlefish is best determined by dentary studies,a process which usually occurs on fish harvested during snagging season,a popular sport fishing activity in certain parts of the U.S.The dentary is removed from the lower jawbone,cleaned of any remaining soft tissue,and cross-sectioned to expose the annual rings.The dentary rings are counted in much the same way a tree is aged.Dentary studies suggest that some individuals can live 60 years or longer,and that females typically live longer and grow larger than males.