As a fledgling birder in the 1960’s, my chief source of bird information was my cherished Golden Guide Birds of North America by Chandler Robbins and the artist Bertel Bruun. At the time, the Robbins guide and Roger Tory Peterson’s guide were the only two field guides available. To be sure, Peterson’s illustrations were far superior to those of Bruun but the text, the plates and the range maps were in different parts of the Peterson guide. The Robbins guide had text, illustrations, maps and sonograms of each species on facing pages. Plus, all of the bird species in North America were covered.
These memories spring to mind because Chan recently passed away at the age of 98. His contributions to ornithology and to birding were immense. The Golden Guide was just one of his many accomplishments.
Chan took a job as a biologist with the U.S. Fish and Wildlife Service in 1945. He was based at the Patuxent Research Refuge in Maryland until his retirement in 2005 after 60 years or service! Even in retirement, he continued to work as an emeritus biologist for another 13 years.
Early in his career, he conducted research on the effects of DNA on birds. He worked closely with Rachel Carson, one of Maine’s own, and his work on the deleterious impact of DDT provided scientific support for Carson’s Silent Spring, published in 1962.
Concerned about tracking the effect of DDT on bird populations, Chan realized that we lacked a rigorous method to assess changes in bird populations at the regional and continental level in North America. Chan remedied that problem by designing the Breeding Bird Survey (hereafter, BBS), a citizen-science project that provides a view of the changes of breeding bird populations throughout North America.
A BBS is conducted along a 24.5-mile stretch of secondary roads. Once during the breeding season, an observer starts at the designated starting point about half an hour before sunrise. The observer listens and looks for birds for three minutes, drives 0.5 mile to the next stop, observes for three minutes and so one until 50 stops are sampled.
The observer samples the same route each year, reporting the data to the BBS office.
Nearly 3,000 BBS routes are sampled yearly. Modest contributions from many yield a powerful tool for detecting declines or increases of our avifauna.
The BBS data are available to researchers. Over 400 papers been published with the data. One of the most influential of these papers was a 1989 article written by Chan and his colleagues. They showed that an alarming number of long-distance migrants showed decreasing abundance on the breeding ground in North America. Related species that did not migrate to the tropics were not showing such steep decreases in abundance. Hence, the authors could infer that deforestation and other habitat degradation in the tropical wintering areas of these long-distance migrants could explain lower densities in North America. This work provided a strong impetus to redouble efforts at habitat conservation.
Chan visited Midway Island in the Pacific ten times during this career. His work involved banding Laysan Albatrosses that nest there. In 1956, he banded an albatross, subsequently named Wisdom. Wisdom is still alive and reproducing at the ripe age of 60! Wisdom is the oldest banded bird ever.
I got to know Chan from ornithological meetings. I well remember chats we had after presentations I made. He was a kind, soft-spoken and generous man. He was also a highly skilled observer. His eyes and ears were amazing.
For many years, I conducted BBS routes in Maine. After conducting my 50th BBS census, I received a certificate of appreciation from the BBS Office along with a signed copy of the Chan’s Birds of North America. I am very proud of the book, which sits on my shelf next to my tattered childhood copy.