Re: [MDOsprey] Goshawk Migration
Guineabird@aol.com
Sun, 21 Nov 1999 15:22:11 EST
In a message dated 11/20/99 10:50:59 PM Eastern Standard Time,
scash@mindspring.com writes:
<< I don't believe the difference is one of distance - it's more one of
frequency/regularity. Goshawks are considered nonmigratory because they
regularly overwinter on their breeding grounds - there is not the clockwork
seasonal shift seen in migratory species. The dispersal of Goshawks (and
other irruptive nonmigratory species, such as the "Winter Finches", et al.)
is related to a shortage of food on their wintering grounds - they're not
actually migrating to a specific spot year after year, they're just
wandering, looking for food, b/c there may not be enough rabbits/grouse up
North this year, perhaps last year was particularly productive for breeders
(and there are therefore too many individuals for the wintering grounds to
support).
Migratory birds are actually *resident* on their wintering grounds, which
is usually a set area (perhaps even the same location year after year, in
much the same way as many breeders use the same nest or tree year after year)
but migrate somewhere else (North to the US or Canada in the case of most of
our Neotropicals) to breed, which differs fairly markedly from species such
as the Goshawk, etc. Hope that helps, not sure I was clear enough,
Sandy Cash
scash@mindspring.com
Carrboro, NC >>
Thank you Sandy - It sure did help - Your explanation was very clear!
Gail Frantz
Reisterstown, MD