Boreal Owls captured for banding at Hartley Field in Duluth, November 2000. Photo

by Frank Nicoletti.

used. In contrast, my study area was spe-

cifically selected for the capture of mi-

grating Boreal Owls and birds were lured

into the nets.

The timing of Boreal Owl migration

and possibly the age ratio also appears to

vary from one location to another within

our region. A total of 159 Boreal Owls

was banded between 23 September and

31 October 2000 (no banding attempted

after 31 October) at Whitefish Point Bird

Observatory, Chippewa County, Michigan

(Berigon and Whitmore 2000). The age

breakdown among the 159 was 44.65%

HY, 42.14% AHY, and 13.21% unknown.

The percentage of HY birds was much

higher at Whitefish Point compared to

this study, but as mentioned earlier, the

age data were probably skewed by small

sample size and a relatively short period

of sampling. Sampling in November may

have missed age and sex differences in

Boreal Owl fall migration, which has not

been adequately studied in Minnesota.

The relatively short period of time dur-

ing which Boreal Owls were captured at

Hartley Field further limits interpretation

of the resu lts from this pilot study. Based

on fall seasonal reports in The Loon for

the past 25 years, Boreal Owls have been

discovered at Hawk Ridge and elsewhere

in northeastern Minnesota throughout

October and November, but most have

been found between 10 October and 20

November, with a peak migration in early

November. It should also be noted that

several of these published records were

undated and that some reports probably

did not represent true migrants.

The general health of the 24 Boreal

Owls captured and banded in November

2000 seemed good, although there were

many reports of starving or dead Boreal

Owls by late Februa1y 2001. As outlined

elsewhere in this issue, Boreal and other

species of northern owls irrupted during

Fall2001

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