Christmas Bird Counts then and now
On London’s Christmas Bird Counts in the early 20th century Northern Shrikes were a hit-or-miss species. That is still the case today. Photo by Paul Nicholson.
’Tis the season for Christmas Bird Counts across the Western Hemisphere. The count window is from December 14 to January 5.
The Christmas Bird Counts (or CBCs) started in Toronto and 24 other locations across North America in 1900. They are the world’s longest-running citizen science initiative. During the weeks on either side of Christmas, birders the fan out on routes within defined count circles and complete a census of birds. London’s CBC has been occurring since 1910.
The City of London has grown in recent years beyond its original count circle, especially in the northeast part of the City. The CBC is carried out in London only at routes and feeders that fall within the circle.
It’s interesting to reflect on what remains the same and what has changed with the counts over the past many decades.
Technology has changed the look of CBCs. Instead of relying completely on paper records, data collected on each of the routes within a count circle can now be reported online using the eBird platform. The data are consolidated electronically too, and they are ultimately accessed by researchers digitally.
The value of the citizen science data is still very powerful. In fact, because of the usefulness of the early CBCs, many more count circles have been added. There are now more than 2,000 count circles across the Americas. Also, many more citizen science initiatives such as the Great Backyard Bird Count, Breeding Bird Atlassing, Project Feederwatch, and Swiftwatch have sprung up.
Some of the bird species seen in London have remained the same over the past century. In a January 7, 1939 London Free Press column titled “The Christmas Census”, naturalist W.E Saunders reported that American Tree Sparrows, Golden-crowned Kinglets, Herring Gulls, and Downy Woodpeckers were all seen in good numbers on the count day.
Some of the species that were hit or miss in the early 1900s are still hit or miss on the London count now. For example, Saunders wrote about the Northern Shrike having been an expected sighting that was missed. “We felt rather confident about this fellow, in advance, because several of us had seen him in recent weeks.”
Some of the bird species have changed. Saunders noted that “the Black-backed Woodpecker was found in its customary area, busily hunting those insects that work under the bark of dead spruces.” He also commented that Lapland Longspurs had frequently been seen almost up to December 25. There were 50 Lapland Longspurs on that year’s CBC. Another eye-catching tally was the Ring-necked Pheasants with a total of 34 individuals having been seen.
This year, no-one would expect Black-backed Woodpecker or flocks of Lapland Longspurs to be seen on the London CBC routes. If multiple sightings of Pheasant were logged, most would be attributed to birds escaped from a game farm.
On the other hand, London birders now routinely have species such as Carolina Wren and Red-bellied Woodpecker on the count.
Bird scientists study the year-over-year CBC data in an effort to determine what has caused the population shifts. In some cases it will be habitat loss or insecticides or range change driven by climate change.
Some common bird names have changed in the past hundred years. Saunders referred to Snowbirds instead of Dark-eyed Juncos and he called the Northern Shrike a Butcherbird.
It is interesting to see that the Northern Cardinal populations have remained robust in the London area for more than a century. Saunders reported on scores of them decades ago and they can still be seen and heard in good numbers today. This is one of the many reasons that the Northern Cardinal was officially proclaimed to be the City of London’s official bird in 2021.