Migratory Double Breeding
I’ve always thought of bird migration as a simple (but increasingly arduous) journey between a southern hemisphere wintering ground and a northern hemisphere breeding range. Now that notion has been debunked.
Three ornithologists (from the University of Washington and Environment Canada in Saskatchewan) have recently discovered that at least five neotropical species of birds after successfully breeding in their northern habitats stopped over in midsummer to breed a second time during the same summer in coastal western Mexico or Baja California. They then continued their migration further south to their final wintering areas in the Neotropics.
The five species are yellow-billed cuckoos, orchard orioles, hooded orioles, yellow-breasted chats and Cassin’s vireos. Only the orchard oriole breeds in Manitoba, but it is not often easy to find here. Any indication that it is more fecund than previously known is welcome news.
For further information, check Science Daily: www.sciencedaily.com