[rec.birds] Wintering in the Summertime

jclarke@remus.rutgers.edu (James C. Clarke) (06/05/91)

	I hope that this is the right forum for this question.  There are a great number of birds in North America that winter in South America, some as far as Argentina.  Now, I suppose that these birds are "wintering" in a locale that is then in it's summer. I would also assume that these birds are non_breeding and interact with local bird population which is breeding.  With the exception of a few pelagic species, such as a several species of Albatross, are they any species of bird that the main portion of the 








species "winters" in the Northern Hemisphere's summer?  I can't think of any. 


					J. Christopher Clarke
					jclarke@remus.rutgers.edu

dmark@acsu.buffalo.edu (David Mark) (06/06/91)

In article <Jun.5.09.00.22.1991.9090@remus.rutgers.edu> jclarke@remus.rutgers.edu (James C. Clarke) writes:
>
>	I hope that this is the right forum for this question.  There are a 
  great number of birds in North America that winter in South America, some as 
  far as Argentina.  Now, I suppose that these birds are "wintering" in a 
  locale that is then in it's summer. I
> would also assume that these birds are non_breeding and interact with local 
  bird population which is breeding.  With the exception of a few pelagic 
  species, such as a several species of Albatross, are they any species of bird 
  that the main portion o
>species "winters" in the Northern Hemisphere's summer?  I can't think of any. 

I can't think of any, either.  There are other southern-breeding seabirds
that are here in our summer (their winter), such as most shearwaters and
storm-petrels.  But no land birds that I know of.  But it is not surprising,
I think.

Almost all latitudinal migrants breed in the temperate or arctic zones.
Tropical breeders tend to be sedentary, or altitudinal migrants.  The temperate
land area in the southern hemisphere is rather small.  For example, Uruguay
is the only South American country that has no part in the 'tropics'
(between 23-23 N and 23-23 South).  Similar small temperate areas in
Africa and Australia.

Next, relatively few of our breedings birds go all the way through to the
temperate zone or antarctic zone.  The only land birds I can think
of right now that do that are some of the swallows.  Others would be many
shorebirds and seabirds.  Most of our migrants stop in the tropics, or north 
of the tropics.

So, on hand-waving probability alone, it is not surprising that transtropical
migrants that are southern breeding landbirds are uncommon or absent from the 
planet. (In Australia, only a dozen or so land birds leave the country entirely 
in winter (Dollarbird, several cuckoos), and they do not regularly go beyond the
tropics.)

David Mark
dmark@acsu.buffalo.edu

andrewt@cluster.cs.su.oz.au (Andrew Taylor) (06/06/91)

In article <79080@eerie.acsu.Buffalo.EDU>, dmark@acsu.buffalo.edu
(David Mark) writes:
[ A good answer as to why North hemisphere wintering landbirds are rare ]

But he gets no points for trivia knowledge - there is at least one such 
bird - the African Penant-Winged NightJar!

Andrew (starting his African trip in 5 days) Taylor

math0065@waikato.ac.nz (06/11/91)

In Article  "Wintering in the Summertime" Date: 5 Jun 91 13:00:23 GMT
jclarke@remus.rutgers.edu (James C. Clarke) writes

> I hope that this is the right forum for this question.  There are a great
> number of birds in North America that winter in South America, some as far as
> Argentina.  Now, I suppose that these birds are "wintering" in a locale that is
> then in it's summer. I would also assume that these birds are non_breeding and
> interact with local bird population which is breeding.  With the exception of a
> few pelagic species, such as a several species of Albatross, are they any
> species of bird that the main portion of the species "winters" in the 
> Northern Hemisphere's summer?  I can't think of any. 

	The only New Zealand species (of land bird) that seems to meet your
requirements is the long-tailed cuckoo (Eudynamis taitensis) which regularly
breeds in Stewart Island (47 S), and straggles to the Auckland Islands (51 S),
but migrates in our winter time as far north as the Marshall and Caroline
Islands (~10 N).  All the same, the main wintering range is south of the
equator, from Fiji east to Tahiti.

	The comment of from dmark@acsu.buffalo.edu (David Mark) of 6 Jun 91 
11:25:29 GMT:

> Next, relatively few of our breedings birds go all the way through to the
> temperate zone or antarctic zone.  The only land birds I can think
> of right now that do that are some of the swallows.  Others would be many
> shorebirds and seabirds.  Most of our migrants stop in the tropics, or north 
> of the tropics.

is quite relevant, though.  If one insists that the migrants cross the equator,
then even the list of "normal" northern birds wintering south is much reduced.

Hamish Spencer (h.spencer@waikato.ac.nz)