The bird’s nest is primarily built to prevent the eggs from rolling away and provide warmth for the eggs. Nests will come in different sizes and shapes. The very first bird nests were most likely built on the ground, by a bird that scrapes away at the earth in order to create a cavity. Today, there are still birds that use these basic constructions – and they are called “scrapes”.
You may assume that all ground nesting birds are flightless. However, not all of them are actually flightless. In fact, not all flightless birds are nesting on the ground. Pelicans, emu, ostrich and tinamou lay their eggs in a scrape. Kiwis are also ground nesters; however, they lay their eggs in a burrow.
Most shorebirds can fly; but still, their habitat is not well stocked in trees. Most of them nest on the ground but only in areas that are inaccessible for possible predators.
Weak fliers like partridge, pheasant and quail build nest on the ground. Typically, they nest in grain fields where they can find seclusion and shelter. Some quails though have been recorded to have built nests in open spaces.
It is not actually the lack of trees or flight that causes a bird to nest on the ground. Bustards, which are the heaviest bird of flight in the world, nest on the ground. To protect their nests from predators, they use camouflage.
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