[mou] Great Gray Owls, remarks on 2005-2006

[Jim Williams]

Today, I posed some Great Gray Owl questions to Dr. James Duncan, the=20
Winnipeg owl researcher who also does work in Roseau County. Here is=20
the exchange.
Jim Williams
Wayzata

=3D=3D=3D=3D

Hi Jim,

Good to hear from you.  I attempted to answer your questions below in=20
CAPS the best I can, recognizing that the information I am providing is=20=

not from the main MN owl invasion area. Things could be quite different=20=

there regarding great grays and meadow voles compared to Roseau County=20=

and southern Manitoba!

Cheers, Jim
________________________________________
Dr. James R. Duncan, Manager
Biodiversity Conservation Section
Wildlife and Ecosystem Protection Branch
Manitoba Conservation
Box 24, 200 Saulteaux Crescent
Winnipeg, MB R3J 3W3=A0
Wildlife Web Site=A0 www.manitoba.ca/conservation/wildlife =A0
CDC Web Site=A0 http://web2.gov.mb.ca/conservation/cdc/


Can we expect the owls to return in numbers this winter?
YES - OUR LONG-TERM WINTER DATA SUPPORT WHAT I CALL AN "ECHO EFFECT",=20
IN WHICH THE ONLY SIGNIFICANT TIME SERIES CORRELATION IN WINTER NUMBERS=20=

OF GREAT GRAY OWLS FROM YEAR TO YEAR IS THAT IN THE YEAR IMMEDIATELY=20
AFTER AN INVASION/IRRUPTION YEAR, THERE IS TYPICALLY HALF AS MANY GREAT=20=

GRAY OWLS AS THE INVASION/IRRUPTION YEAR.

How did the owls fair on the breeding territories this spring and
summer? Was their a normal pattern of breeding? Did the birds enjoy
breeding success?
NO GREAT GRAY OWLS NESTING IN THE NEST STRUCTURES I MONITOR IN MB AND=20
ROSEAU COUNTY, MN, IN SUMMER 2005.

How is the prey population for these birds, spring, summer, and present?
I ONLY MONITOR SMALL MAMMALS ONCE A YEAR (OCTOBER) IN MY MB AND MN=20
(ROSEAU COUNTY) STUDY AREAS, AND ONLY IN HABITATS WHERE GREAT GRAY OWLS=20=

ARE KNOWN TO HUNT.  THE GREAT GRAYS IN MY STUDY AREA  EAT >90% MEADOW=20
VOLES, THEREFORE I AM COMMENTING ON NUMBERS OF THAT PREY SPECIES ONLY.=20=

THIS YEAR THE NUMBER OF MEADOW VOLES ON MY STUDY AREAS WERE STILL VERY=20=

LOW, BUT APPEAR TO INCREASING SLOWLY, A NORMAL PATTERN.  I EXPECT=20
MEADOW NUMBERS IN MY STUDY AREA TO BE MORE NUMEROUS NEXT YEAR, AND=20
COINCIDENTALLY TO HAVE OWLS NESTING IN 2006.

What other comments might you offer?
THE RESULTS OBSERVED ON OUR STUDY AREAS SHOW A NORMAL CYCLIC PATTERN OF=20=

THE FLUCTUATIONS IN THE NUMBER OF BREEDING GREAT GRAY OWLS AND THEIR=20
TYPICAL PREY, THE MEADOW VOLE.