Esox Lucius - Northern pike Esox lucius is found in freshwater throughout the northern hemisphere, including Russia, Europe and North America. It has also been introduced to lakes in Morocco and is even found in brackish water of the Baltic Sea |
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The northern pike gets
its name from its resemblance to the pole-weapon known as the pike (from
the Middle English for pointed). The genus name, Esox, comes from the
Greek and Celtic for "big fish" and "salmon". Various
other unofficial trivial names are: American pike, common pike, great
northern pike, Great Lakes pike, grass pike, slough shark, snake, slough
snake, northern, gators (due a head similar in shape to that of an alligator),
jack, jackfish, and Mr. Toothy. Description Northern pike are most often olive green, shading into yellow to white
along the belly. The flank is marked with short, light bar-like spots
and there are a few to many dark spots on the fins. Sometimes the fins
are reddish. Younger pike have yellow stripes along a green body, later
the stripes divide into light spots and the body turns from green to
olive green. The lower half of the gill cover lacks scales and they have
large sensory pores on their head and on the underside of the lower jaw
which are part of the lateral line system. Unlike the similar-looking
and closely related muskellunge, the northern pike has light markings
on a dark body background and fewer than six sensory pores on the underside
of each side of the lower jaw. A hybrid between northern pike and muskellunge is known as a Tiger Muskellunge depending on the sex of each of the contributing species). In the hybrids, the males are invariably sterile, while females are often fertile, and may back-cross with the parent species. Another form of northern pike, the silver pike, is not a subspecies but rather a mutation that occurs in scattered populations. Silver pike, sometimes called silver muskellunge, lack the rows of spots and appear silver, white, or silvery-blue in color. Length and Weight Pike grow to a relatively large size; lengths
of 150 centimetres (59 in) and weights of 25 kilograms (55 lb) are
not unheard of. The heaviest specimen known so far was caught in an
abandoned stone quarry, in Germany, in 1983. She (the majority of all
pikes over 8 kg or 18 lb are females) was 147 cm (58 in) long and weighed
31 kg (67 lb). The longest pike ever recorded was 152 cm (60 in) long
and weighed 28 kg (61 lb). Historic reports of giant pike, caught in
nets in Ireland in the late 1800s, of 41 to 42 kg (89 to 92 lb), were
researched by Fred Buller and published in "The Domesday Book of Mammoth Pike".
The British Isles have not managed to produce much in the way of giant
pike in the last 50 years and as a result there is substantial doubt
surrounding those earlier claims. Currently, the IGFA recognizes a
25 kg (55 lb) pike caught by Lothar Louis in Lake of Grefeern, Germany,
on 16 October 1986 as the all-tackle world record northern pike. Northern
pike in North America seldom reach the size of their European counterparts;
one of the largest specimens known was a 21 kg (46 lb 2 oz) specimen
from New York state. It was caught in Great Sacandaga Lake on 15 September
1940 by Peter Dubuc. There are reports of far larger pike, but these
are either misidentifications of the pike's larger relative the muskellunge,
or simply have not been properly documented and belong in the realm
of legend. Dutch Mammoth Pike caught by Ewout Blom Habitat |
The color of the sticky eggs is yellow to
orange, the diameter is 2.5 to 3 mm. The embryos are 7.5 to 10 mm in
length and able to swim after hatching but stay on the bottom for some
time. The embryonic stage is 5 to 16 days, dependent on water temperature
(at 19°C and 10°C,
respectively). Under natural circumstances the survival from free swimming
larva to 75 mm pike is around 5 percent. Pike can reach the reproductive
stage in a year, females being 30 cm, males 19 cm. Pike normally live
5 to 15 years, but can be as old as 30. Life expectancy and growth are
dependent on circumstances. Some Canadian populations have many old slender
pikes, Baltic pike grow to great lengths in a short time while eating
nutrient rich herring. The young free swimming pike feed on small invertebrates starting with daphnia, and quicky moving on to bigger prey like isopods like asellus or gammarus. When the body length is 4 to 8 cm they start feeding on small fish. The pike have a very typical hunting behavior, they are able to remain
stationary in the water, by just moving the last fin rays of the dorsal
fins and the breast fins. Before striking they bend their body and dash
out to the prey using the large surface of tail fin, dorsal fin and anal
fin to propel themselves. The fish has a distinctive habit of catching
its prey sideways in the mouth, immobilising it with its sharp backward
pointing teeth, and then turning the prey headfirst to swallow it. It
eats mainly fish, but on occasion water voles and ducklings have also
been known to fall prey to pike. Young pike have been found dead from
choking on a pike of a similar size, an observation referred to by the
renowned English poet Ted Hughes in his poem 'Pike'. Northern pike also
feed on frogs, insects and leeches. It has often been suggested that
pike optimally forage on prey that are from 25 to 35% of their body length.
They are not very particular and eat spiny fish like perch and will even
take sticklebacks if that is the only available prey. |
