2022 Christmas Bird Count
There are many factors (weather, temperature, visibility, number of counters, food supply, suitable habitats, etc.) that influence the outcomes of the annual Christmas Bird Counts (CBC). Either singly or in combination, they can cause great variations within count areas, between adjacent count areas and the whole region. This year was a good example of these influences.
Our count area is made up of Mayne, North and South Penders, and Saturna Island. Each island counts on the same day and in roughly the same weather conditions, and has, per capita, about the same ratio of counters. If we look at total numbers for the 2022 count by island, we see that Mayne tallied 4631 birds and 65 species, while the Penders tallied 5172 birds and 86 species, and Saturna tallied 3944 birds and 72 species; quite a difference over a relatively small geographic area. This represents 92 different species and 13,862 birds tallied for the Pender Islands Audubon Count Circle, of which Mayne is a part.
When we dive into some specifics we can see some other interesting differences.
Let’s look at a few examples for marine species:
SPECIES | MAYNE | PENDERS | SATURNA |
Pacific Loon | 196 | 16 | 0 |
Western Grebe | 1 | 33 | 20 |
Pelagic Cormorant | 8 | 45 | 141 |
Common Merganser | 17 | 149 | 31 |
Some examples for other water birds:
SPECIES | MAYNE | PENDERS | SATURNA |
Ring-necked Duck | 0 | 239 | 0 |
Black Oystercatcher | 29 | 3 | 114 |
Short-billed Gull | 27 | 80 | 157 |
Iceland Gull | 161 | 0 | 1 |
And, some land birds:
SPECIES | MAYNE | PENDERS | SATURNA |
Golden-crowned Kinglet | 245 | 69 | 45 |
American Robin | 287 | 864 | 464 |
European Starling | 320 | 197 | 13 |
At a general level you could attribute these variations across the islands to suitable feeding and roosting habitats at that time. Birds do move around and exploit suitable habitats in larger geographic areas. The CBC is just a snapshot of a one-day distribution picture. Nonetheless, the numbers for some of the species and where they are more numerous can be explained more specifically. For instance, the Pacific Loon is a trigger species for the designation of the Active Pass Important Bird Area (IBA) which means it has been consistently found here in high numbers over time. So the key conditions for its winter survival are met by the tidal waters of the Pass.
The Ringed-neck Duck prefers shallow, fresh, and wetland-fringed water bodies for winter feeding. It is uncommon on Mayne and Saturna but consistently numerous on the Penders. This is partly to do with the Penders having numerous small to medium sized lakes throughout its landscape, the other two islands do not. The Iceland Gull (formerly Thayer’s Gull) has been increasing in numbers around Mayne Island over the last 5-10 years. Right now the Active Pass IBA seems to be a preferred area for this species. The reason for this redistribution is not known. The numbers for the European Starling are interesting and could be reflecting this species’ preference for fragmented habitats and agricultural areas. Both Mayne and Pender have areas of fragmentation while Saturna is mostly intact forest.
So how did we do for the 2022 count? As noted, we tallied 65 species and 4,631 birds on December 17, 2022. We also had two Count Week birds that were seen just before and just after the actual count day. They were the Barred Owl and the Northern Saw-whet Owl. We had 19 parties (38 people) distributed across the island counting birds during that day. Collectively, these parties spent just over 80 hours counting and travelled close to 75 kilometers on foot and 36 kilometers by car.
Our top ten birds were Dark-eyed Junco at 992 or 21% of the total count; European Starling at 320 or 7% of the count total; American Robin at 287 or 6% of the total; Golden-crowned Kinglet at 245 or 5% of the total; Canada Goose 229 or 4.9% of total; Pacific Loon at 196 or 4% of the total; Iceland Gull at 161 or 3.5% of total; American Wigeon at 156 or 3.5% of the total; Unidentified Gull species at 146 or 3% of the total; and Chestnut-backed Chickadee at 129 or 2.7% of the total. Collectively, these ten species represent 60% of the count birds.
Notable species and numbers of birds for this year include four Trumpeter Swans, eight Marbled Murrelets, forty-eight Golden-crowned Sparrow and forty-eight Anna’s Hummingbirds.
Thanks to all the participants for their time and energy for the 2022 Christmas Bird Count!
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