As a rule of thumb, pike heavier than ten pounds tend to be exclusively
female, male pike larger than twelve pounds are uncommon, but pike under eight
pounds could be of either sex.
pike are capable of producing a large number of eggs. For example a twenty pounder
could lay some 200,000 eggs. Females contain eggs at some stage of development
for most of the year. Egg development begins during the summer months following
the springtime spawn. During the following winter and spring the eggs mature and
swell by absorbing water.
trigger depends on various factors including water temperature which is usually
between 8 and 12 degrees celsius when spawning takes place. Male pike tend to
arrive at the spawning ground before the females, selecting shallow areas of water
where there ample submerged water plants or emergent vegetation - reed, rushes
or even flooded areas of grass can be used.
is some evidence of loyalty to particular spawning sites, mainly in rivers; pike
use the same feeder ditches year after year. It may even be that small pike return
in later life to the places where they were hatched.
pike may fail to shed their eggs when there are large temperature fluctuations
during the spring. Unlike some other coarse fish they appear to be incapable or
re-absorbing these eggs - which can constitute 20% of their body weight - and
by early summer these fish often die.
pike eggs hatch after 20-24 days but fry survival may be very low. For example,
in one study of 1.25 million eggs produced 180 pike lived to one year of age,
fifty lived to two years, 39 to 3 years, 20 to 4 years and only nine survived
to five years of age.
the pike population is largely determined by survival of the younger stages in
the life cycle, rather than the number of parents or the quantity of spawn which
is shed. Predation and starvation are the prime causes of larval mortality.
extent of pike on pike predation has particularly important consequences for the
survival of pike during their juvenile stages. Figures of 79% of losses of young
pike through cannibalism have been reported.