大象传媒

How do finches share out resources? Springwatch has been following chaffinches, linnets, greenfinches and goldfinches all of whom nest in different locations to share out space. The chaffinch normally nests right up against the trunk of the tree, about five metres up, camouflaging the nest with moss and lichen. The goldfinch nests about six metres up in the thinnest twigs as protection from predators. They also have to share the local food. Chaffinches mostly eat invertebrates at this time of year and feed on the ground a lot. Goldfinch and greenfinches feed their chicks on regurgitated seeds. The goldfinch has a fine pointed beak and takes very small seeds. The greenfinch takes larger seeds. The linnet also had a narrow beak, but it feeds on seeds from farmland weeds, which is one reason for its decline. Scientifically, this spacing out in the habitat is called niche separation. And it works - it's why we have so many species on Earth.