Top of the chain
Predators at the top of the food chain tend to be the biggest animals in it. These are sometimes called apex (meaning ‘at the top’) predators. Usually nothing else eats them.
Who's at the top of a food chain?
In the UK, apex predators include foxes, otters, owls and eagles.
Other ecosystems around the world have even bigger ones, including lions, polar bears and great white sharks.
Remember, some food chains can be very short, so elephants are huge but they are only the second level in a food chain because they only eat plants.
Predators control a food chain from the top. They keep down the number of herbivores, so that plant food is not all used up, and they keep their prey population healthy by weeding out old or sick ones. Removing predators can spell disaster.
Hunters in the USA once tried to increase the deer population by shooting out wolves and pumas. With their predators gone, deer increased too fast and soon used up all their food. The deer vanished, and so did many other creatures that shared their habitat.
And just think where we would be without the decomposers to rot down all the creatures that don’t get eaten – knee-deep in dead things before you know it!
No room at the top
To make sure that there is enough food to go round, big predators space themselves out.
For instance, golden eagles eat grouse and hares, but there is a limited supply of this prey in their mountain habitat. So one pair of golden eagles may defend an area of more than 100 square kilometres. It won’t allow any other eagles to enter, because they will compete for the available food.