I thought those who do not get Birdchat listserv would like to read this=A0=
posting. =0A=A0=0AMike Hendrickson=0ADuluth, Minnesota=0AWebsite: http://we=
bpages.charter.net/mmhendrickson/=0ABlog: http://colderbythelakebirding.blo=
gspot.com/=0A=0A=0A=0A----- Forwarded Message ----=0AFrom: Jean Iron <jeani=
[log in to unmask]>=0ATo: [log in to unmask]: Wednesday, No=
vember 26, 2008 12:54:05 PM=0ASubject: [BIRDCHAT] Snowy Owl Flight Year - C=
ause(s)=0A=0ASnowy Owls are being seen south of the Arctic in high numbers =
this fall. Most of the early arriving owls have been first year males hatch=
ed last summer. Reports last summer indicated that lemming numbers were hig=
h across the Eastern Canadian Arctic from Churchill, Manitoba, to Bylot Isl=
and, Nunavut.=0A=0AWe previously reported that the cause of the Snowy Owl f=
light was a lemming crash in the Eastern Arctic. However, we've had recent =
correspondence indicating the cause of the flight was a very good breeding =
season, which produced high numbers of young Snowy Owls. Gilles Gauthier an=
d his PhD student Jean-Francois Therrien of Laval University in Quebec City=
 report that based on "the high abundance of lemmings we observed on Bylot =
Island and at all sites we visited on Baffin Island last summer, we predict=
ed that the abundance of Snowy Owls should be very high this winter (in the=
 south). Indeed, some analyses made by Jean-Francois using the Christmas Bi=
rd Count data showed a good correlation between the abundance of lemmings o=
n Bylot Island and the number of owls observed the following winter in Queb=
ec and Ontario for the period 1993 - 2007. So far, our prediction is nicely=
 upheld."=0A=0ASo was there also a lemming crash that is contributing to th=
e Snowy flight? Bruce Di Labio did environmental surveys on southern Baffin=
 Island in August and in central/southern Baffin in September and October. =
He reports that very few lemmings were caught in live traps. This might be =
an indication of a lemming decline in September and October when most resea=
rchers were not in the Arctic. Lemmings normally crash in fall and winter a=
fter a period of high abundance and cycles are usually synchronous across t=
he Eastern Arctic.=0A=0AThe Snowy Owl flight this fall and winter could be =
caused solely by high numbers of young being fledged this summer due to hig=
h lemming populations. Or is the flight the result of a good breeding year =
and a subsequent decline in lemming numbers this fall? If a large number of=
 adult Snowy Owls come south this winter then we'll be more confident in sa=
ying that a lemming crash has occurred. We'll post updates as we get new in=
formation.=0A=0ABaffin Island lies west of Greenland and is the largest isl=
and in the Canadian Arctic. Bylot Island (lat 73 deg, long 78 deg) is about=
 3000 km (1865 mi) north of Toronto. Bylot is much smaller than Baffin. It =
is at the northeastern tip of Baffin on Lancaster Sound "Northwest Passage"=
..=0A=0AAcknowledgements: We thank Ken Abraham, Bruce Di Labio, Bruce Falls,=
 Gilles Gauthier, Jean-Francois Therrien, and Michel Gosselin for informati=
on and discussions about lemmings and Snowy Owls.=0A=0ARon Pittaway and Jea=
n Iron=0AToronto and Minden, Ontario=0ACanada=0A=0ABirdChat Guidelines: htt=
p://www.ksu.edu/audubon/chatguidelines.html=0AArchives: http://listserv.ari=
zona.edu/archives/birdchat.html=0A=0A=0A=0A