McGILL BIRD OBSERVATORY

WINTER POPULATION MONITORING

2009-2010 SEASON SUMMARY

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 WINTER 2009/10

OCT/NOV

DEC

JAN

FEB

MAR

TOTAL

Number of days within winter season

31

31

31

28

27

148

Number of days of observation

19

8

11

12

13

63

Number of banding sessions

7

2

1

2

4

16

Number of birds (and species) banded

185 (14)

9 (6)

17 (5)

21 (4)

85 (9)

317 (17)

Number of birds (and species) repeat

89 (10)

20 (4)

7 (2)

12 (2)

11 (3)

139 (11)

Number of birds (and species) return

6 (4)

-

1 91)

-

8 (4)

15 (5)

Number of species observed

48

27

21

23

40

58

Number of net hours

242

20

8

20

38

312

Number of birds banded per 100 net hours

76.4

45.0

212.5

95.2

95.2

101.6

The winter season at McGill Bird Observatory spans the gap between the fall and spring migration seasons, a total of just over 21 weeks from the last day of October through March 27. Unlike the daily monitoring during migration, activities at MBO in winter are more sporadic, limited largely by weather conditions, especially when it comes to banding. Few other bird observatories this far north are open in winter at all, so even part-time operations can be useful in terms of monitoring the winter occurrence of birds.

This winter was relatively mild, with far below average snowfall. We were able to conduct observations on 42% of days this winter, a substantial improvement over the past couple of years. During this period we banded 317 birds, eclipsing by one the record of 316 set in winter 2005/2006. Although American Goldfinch topped the charts, the number of Black-capped Chickadees (54) banded was perhaps more suprising, as we would have expected a stable wintering population, but over half of these birds were banded in February or March, suggesting some movement of individuals during winter.  House Finch movement patterns also confounded us - we banded 32 in November and December, but have not caught a single one yet in 2010!   Also of note this winter was a record count of American Tree Sparrow (38), more than doubling the cumulative total over all previous winters.  On the downside, Common Redpolls were completely absent this winter, we had only a single observation of Pine Siskin, and Bohemian Waxwing sightings were infrequent too.

The winter season actually started off slowly with 27 species observed, down from last year’s 36. This number stayed more or less consistent throughout the season, despite variation in the number of observer days. This is likely due to the stabilizing effect of the feeders.  Overall we ended up with 51 species observed, up from last year’s 40, and similar to the 49 in 2006 - 2007. There were a few more observation days this year, compared to last year, but we attribute the higher number of species to the full feeders, and not the added observers.

Top 5 species banded (# of individuals)

Top 5 species observed

1.  American Goldfinch (80)

1.  Canada Goose

2.  Black-capped Chickadee (54)

2.  Red-winged Blackbird

3.  Slate-colored Junco (50)

3.  American Crow

4.  American Tree Sparrow (38)

4.  European Starling

5.  House Finch (32)

5.  Black-capped Chickadee

This winter began with a boom, with nearly 200 birds banded, and 48 species observed - more than have been seen in average winter at MBO over the past 5 years!  To some extent this may reflect a high level of observer effort in November, but it probably also was influenced by unusually mild temperatures for much of the month, allowing some late fall migrants to linger longer than they typically would.  At the other end of winter, March temperatures were also far above normal, and many early spring migrants arrived before the end of what we usually consider to be winter.  Overall, the count of 58 species observed this winter shattered the previous record of 51.

Other interesting highlights include MBO's first Townsend’s Solitaire, discovered on the last day of fall but lingering into early November, two White-throated Sparrows that overwintered at MBO,  a recapture of a male Red-winged Blackbird first banded in 2005, and the first European Starling banded in winter since 2007.  The warm weather in March seemed to provoke some early arrivals; most noticeable was the very early return of female Red-winged Blackbirds to the site.

Many thanks to Alain Goulet, owner of Centre de Conservation de la faune Ailée-Nature Expert, who supplied the seed for our feeders and to all the volunteers who helped with the winter program.

Below, for comparison, is the summary table from 2008-2009; the entire seasonal report and weekly records can be found in the banding log.

 WINTER 2008/09

OCT/NOV

DEC

JAN

FEB

MAR

TOTAL

Number of days falling within winter season

31

31

31

29

27

149

Number of days of observation

7

2

4

9

14

36

Number of banding sessions

-

-

-

-

3

3

Number of birds (and species) banded

-

-

-

-

32 (6)

32 (6)

Number of birds (and species) repeat

-

-

-

-

0 (0)

0 (0)

Number of birds (and species) return

-

-

-

-

6 (4)

6 (4)

Number of species observed

27

22

20

28

39

51

Number of net hours

-

-

-

-

24.0

24.0

Number of birds banded per 100 net hours

-

-

-

-

133.3

133.3

 

-

 

© 2002- The Migration Research Foundation Inc.