Biology
Age/Growth
| Spawning |
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Biology
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The northern pike is a spring spawner and spawning takes place immediately after ice melts in April to early May, when water temperatures are 40° - 50° F (4.4° - 11.1° C). The spawning run in Sibley Park (Lake Simcoe) Ont., began on April 11 with a single female, rose rapidly to a peak in numbers of fish by April 18, declined rapidly and ended by April 20. Mean water temperature over that period was 48.2° F (9° C). In general, this species spawns during daylight hours on the heavily vegetated flood plains of rivers, marshes, and bays of larger lakes. A spawning run of 6000 mature pike was tabulated in a single creek tributary to Waskesiu Lake, Sask (Schultz 1955). The sexes pair at spawning time and a larger female is usually attended by one or two smaller males. They swim through and over the vegetation in shallow water often no deeper than 7 inches (178 mm). At irregular intervals the male and female roll, approximate the vents, and eggs and milt are extruded simultaneously during rapid vibration of the bodies. Each spawning act is usually followed by a thrust of the tails, which moves the fish on and scatters the settling eggs. The act is repeated many times during the day for 2-5 days. | No nest is built; the eggs are scattered at random, usually
in numbers of 5-60 at each spawning act. The eggs which are 2.5-3
mm in diameter, are clear, amber in color, demersal, very adhesive, and
remain attached to the vegetation of the spawning area. Egg numbers
as high as 595,000 have been reported, egg number increases with size of
female and has been estimated as 9000 per pound. The number of eggs
deposited is high, and egg fertility rate is usually over 50%; the number
of young resulting from them is very low. In one habitat in Michigan,
this was estimated at 1800 young leaving the spawning grounds per million
eggs laid, or 99.8% mortality.
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