John Cantelo
Well-known member
Many European & UK birders will be familiar with the concept of 'reverse migration' (although I'm unsure how widely this theory is known elsewhere). This suggests that many Asian rarities turn up in the UK & western Europe as a result of young birds migrating in the opposite direction to that expected (i.e. 180 degrees wrong). However, an article in "British Birds" (James Gilroy & Alexander Lees September 2003) suggested that this theory was flawed. To reduce a complex article to the bare essentials the authors suggest that the apparent concentration of records of rare Asian birds in western Europe more reflects the concentration of birdwatchers there rather than that of rare birds themselves. They suggest that although most young birds depart in the correct direction, in the minority where this navigational trait is faulty, they disperse randomly. Any concentrations in the west being a result of the concentration of birders in western Europe.
Now that paper was a good few years ago so I'm wondering whether the 'reverse migration' idea has now been largely dropped or whether counter arguments have been raised. Also, it seems to me that if 'reverse migration' holds true then it should apply elsewhere in the world. This being an international forum it strikes me as a good place to ask whether it does so,
Now that paper was a good few years ago so I'm wondering whether the 'reverse migration' idea has now been largely dropped or whether counter arguments have been raised. Also, it seems to me that if 'reverse migration' holds true then it should apply elsewhere in the world. This being an international forum it strikes me as a good place to ask whether it does so,