The ritual of getting out early on a cold winter morning, looking for birds in every corner, making detailed species lists, and meeting up with like-minded friends is a beloved holiday-season tradition for many birders. Such Christmas Bird Counts (CBCs) began more than 100 years ago in Delaware County, and continue to this day. The idea for this one-day winter bird census came from ornithologist Frank Chapman, a curator at the American Museum of Natural History in New York. In a widely read article in December 1900, Chapman proposed counting birds as an alternative to the holiday tradition of shooting birds on Christmas Day – unfortunately, mostly for sport, not food – resulting in thousands of birds lost on a single day of the year. In the late 1800s, birds were already declining at alarming rates, although conservation was hardly a concept at the time. His idea took hold quickly, and that year 25 Christmas bird censuses occurred in the United States, including one conducted by Witmer Stone in Delaware county.
The structure of CBCs was formalized in 1941, when the National Audubon Society assumed management of the initiative. It published regulations to document all birds within a defined 15-mile diameter circle, spend at least 4 hours of effort, and avoid overlapping territory. In the years prior, multiple CBCs took place in Delaware County, and a few years missed. Every year since 1922 there was at least one CBC held in the county, with the “Glenolden” circle becoming the official one in the 1940s.
The annual Glenolden/Delaware county Christmas Bird Count lists reflect interesting changes in avian occurrence across the region. In 1949, there were 7 Rough-legged Hawks and a Snowy Owl reported. In 1951, more than 100,000 Northern Pintails were reported – a mind-boggling number by today’s waterfowl standards. The first records of House Finch and Red-bellied Woodpecker occurred in the mid-1950s. The 1962 CBC featured 48 Short-eared Owls and a Black-backed Woodpecker that had been present for 3 weeks in Ridley Creek State Park. In 1978, Double-crested Cormorant and Black Vulture were recorded for the first time.
Increased development and habitat loss in Delaware County caused a decline in the numbers and variety of bird species. The decades since the 1970s highlighted increased participation in CBCs, as new generations of birders brought fresh energy, eyes and ears to the effort. More than 100 years of dedication and effort has yielded a cumulative list of 195 bird species as of December 2023, including a number of local, state, and regional rarities found over the years. This number will no doubt grow, as climate, habitat, and community engagement continue to change.
Join BCDC in a panel conversation with past and present compilers, section leaders, and participants of the long-running Glenolden/Delaware County Christmas Bird Count. Hear how the CBC has evolved over the decades, notable sightings and disappointing misses. Share your predictions for the future, and get inspired for the 2024 Glenolden CBC on December 14.
All are welcome – members and non-members – to our program meetings.
This program is online only, not in person. Click on this Zoom weblink to join online: https://zoom.us/meeting/register/tJYpdOqsrjIjG9SZ4XQxOs6H36dIC2_8bsiF
Photo by Debbie Beer.