Ecological Effects
The migration of birds also aids the movement of other species, including those of ectoparasites such as ticks and lice, which in turn may carry micro-organisms including those of concern to human health. Considerable interest has been taken due to the global spread of avian influenza, however migrant birds have not been found to be a special risk, with import of pet and domestic birds being a greater threat. Some viruses that are maintained in birds without lethal effects, such as the West Nile Virus may however be spread by migrating birds. Birds may also have a role in the dispersal of propagules of plants and plankton.
Some predators take advantage of the concentration of birds during migration. Greater Noctule bats feed on nocturnal migrating passerines. Some birds of prey specialize on migrating waders.
Read more about this topic: Bird Migration
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