Forty-six people collectively logged over 100 hours and 188 km to survey the forests, neighbourhoods, marine waters and the feeders of Mayne Island on December 20, 2020.
Because of the weather predictions we needed to set a date around a better weather window, which proved to be a great decision. We had perfect weather for birding – good light, low wind and mild temperatures. As a result, we were successful in identifying 73 species representing 7,949 total birds. The thirty-two -year average for species is 69 with an average of 4892 birds for total numbers. So our 2020 count numbers were above the long term average and in fact the total number of birds counted was the second highest since we began the counts. A great result you would think, so let’s now look at the individual species numbers of interest.
Two species of birds accounted for 47% of the total birds tallied. They were Pine Siskins (1882) and Dark-eyed Juncos (1837) and both numbers are likely conservative knowing how difficult it is to accurately count constantly moving flocks of small birds. The siskins particularly, were in an irruption year which means that a higher than normal density of the birds move into an area. The scientific consensus is that these irruptions are tied to the success of tree seed crops, which the siskins target. So if there is poor tree seed production in one part of their range, the siskins migrate to areas that have sufficient food supplies. For this year, coincidentally, Mayne Island’s coniferous and deciduous trees had bumper seed production.
The Dark-eyed Juncos, our usual highest number species, were 4 times their historical numbers and while they are also tree seed eaters it is not clear whether this species is influenced by the same food pressures as the siskins.
After these two species, the next highest species numbers were, in descending order, Brandt’s Cormorant (321), Chestnut-backed Chickadee (315), Golden-crowned Kinglet (223), and Canada Goose (213). Interestingly, we had the highest ever count for Anna’s Hummingbird at 83. The bird species of the count this year was the Yellow-rumped Warbler. Thanks to all the participants for their time and enthusiasm particularly in light of the need for COVID safety measures.
Michael Dunn
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