Why are there so few predators compared to the prey animals they hunt?

Answer 1

Balance within the food webPredators are normally bigger so they need more food.Each predator has to kill many prey animals a year to survive and the prey animals have to be numerous enough to reproduce and survive. Too few prey animals and the predators starve to death. In a healthy ecosystem predators and prey reach a balance so that there are always enough prey animals to continue reproducing. This ensures a permanent supply of food for the predators. If the predators over hunt the prey animal, the population of prey will decline causing the predators to starve.The ecosystem will not also be balanced if there are more predators than preys.

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In the food web the producers are always more numerous than the primary consumers who are more numerous than the secondary consumers. It is rare to find tertiary consumers. This is because the amount of energy transfered between the trophic levels decreases meaning that an organism in a higher trophic level has to eat more animals in the level below in order to gain enough energy. The reason for this is that energy is lost from the system due to movement, excretion, reproduction etc.

re: you're smart.

on each trophic level there is a certain number of kilacalories. say the primary consumer has 3500 kilacalories then the secondary consumers only gets 350 kilacalories. only 10% of the energy is passed from level to level the rest has already been absorbed and used. so it takes more primary consumers to feed a single secondary or teriary consumer. so only a certain number of predators can live in a certain area with the amount of food for them and the amount of energy to consume per prey animal.( that's why animals like rabbits and mice have such big litters and can mate more than once or twice a year like the predators most likely do.)