Sperm Motility of Northern Pike and Chain Pickerel at Various pH Values

Abstract

The activity of sperm from northern pike Esox lucius and chain pickerel Esox niger was observed at pH 3.9, 4.5, 5.4, 6.0, 6.4, 6.9, 7.4, and 7.9. The sperm of the northern pike remained motile for shorter periods of time than that of the chain pickerel (P = 0.01). Northern pike sperm was not observed swimming actively at pH values less than pH 5.4 and showed a strong trend toward increased time of activity with increasing pH. For this species, minimum motility occurred at pH 5.4 (28 seconds) and maximum motility was found at pH 7.9 (67 seconds). In contrast, chain pickerel sperm was acid-tolerant, swimming actively for periods of over 90 seconds at pH 3.9 and 4.5. Maximum sperm motility for this species was at pH 6.9 (137 seconds). Motility time for chain pickerel sperm was reduced at the two most basic levels tested: 109 seconds at pH 7.4, and 81 seconds at pH 7.9. Substantial variation in sperm motility time occurred between the two chain pickerel males tested, but not between the two northern pike males.