Immediately after the pike fry is hatched, it attaches itself to underwater vegetation with help of sticky threads. After 9-10 days, the nutrition in the yolk-sack is consumed. The fry, which now is about 0.4 inches long, begins hunting on swimming plankton crayfish. Already from the beginning the pike uses its special hunting technique – hiding in the vegetation to wait for suitable prey to pass by. Later on, the pike fry begins to catch insect larvae, and when it is 0.8 -1.2 inches long, it also begins to eat other fish fry. When it reaches 1.2 inches in length, the fry spread out along the shore. During the late summer when the pike fry has become 4 inches long or greater it lives nearly exclusively on fish.
The pike’s nutrition varies from watercourse to watercourse, and also with the fish’s size. In lakes pike eat small fish in addition to large, so when fishing in waters where one knows that there are large pike, it can pay off to use large lures -likely 20-25 grams.
Among the many features which demonstrates the pike is an effective predator, is the fact it has an extremely elastic stomach. It can be stretched out to nearly twice its normal size, while the circumference can increase to more than the double. A full pike stomach can be stretched until the skin is transparent, so one can see what it has eaten without cutting it open.
According to English experiments, an 8 -12 inch long pike needs a nutrition amount (fish) of 3.4 grams to gain 1 gram of weight. That means the food coefficient is 3.4. Food coefficient is the number of weight units that must be eaten for the fish to put on one corresponding weight unit. It has been concluded that pike under 2.2 lbs have a food coefficient of 10, while pike weighing more(depending on what kind of prey fish is available) it likely eats different kinds of roach fish and any other edible fish. No matter what body of water a pike lives, they can also eat other pike. Studies that have examined a pike’s stomach have found that 5-6% of its nutrition could be from other pike. It also happens that a pike may snatch a duckling or other swimming young birds, as well as water-rats and frogs. In some cases it is proven that a pike will eat crayfish, possibly because there is a shortage of other suitable fish. One common denominator which seems to be the case in the bodies of water a pike would live, is that the pike will mainly eat whichever fish species is most plentiful.
The fish which pike prey on can vary in size. Small pike likely catch fish which are in proportion to the pike’s own size.
It’s a fact that big than 11 lbs have a food coefficient of 30. It is clear that the food coefficient must be higher in cold water than warmer water. Therefore there has to be a certain difference when it comes to pike’s need for food in Canada vs. England. On the other hand, there are studies that indicate a pike’s food coefficient never exceeds 30. It reasons to believe that small pike under Canadian conditions need 4-7 grams of food to gain 1 gram of weight, while larger pike need 8-12 grams. Small pike transform the food they consume to pike meat significantly more efficiently than large pike.
With small pike, approx. 70% of the nutrition goes to growth, but with large pike, it’s only approx. 20%. Small pike, therefore, use less energy for movement, breathing and other functions that are necessary to live. Spawning and the preparations for spawning also demands a lot of energy.
In relation to other fish it shows that the pike make use of nutrition rather effectively. Something that contributes to this is that pike move relatively little amounts and one can see that demonstrated by the pike’s hunting technique, which consumes very little energy. In many places the pike is a very valuable fish because it transforms a lot of less edible fish to first class fish meat.
The food coefficient also shows that it is uneconomic to feed large pike if one wants to have the greatest possible return in fish meat. If pike are caught when they are 1.1 -2.2 lbs even when larger pike live in the water, one will have significantly larger return in pounds of fish than if the pike get the opportunity to grow a lot bigger. When it comes to inland fishing, however, it’s not just a question of how many pounds one gets in return. The watercourse’s value has to be measured for what significance it has for sport fishing. If the possibility to catch really big fish is something that matters it increases the value of a body of water.