At 6:02 pm President Barbara Saunders called the meeting of the Society to order. Vice-President Ken Chaya introduced Tiffany Grade, Squam Lake Project Biologist, whose talk “On the Trail of a Mystery: The Decline of Loons on Squam Lake, New Hampshire,” described efforts to identify the causes of the precipitous decline of the loon population in the 2004-2005 season on a lake made famous by the film “On Golden Pond.” Although the adult numbers have recovered, reproductive success has not improved, with surviving chicks per breeding pair well below the stable rate of 0.48. In New Hampshire as a whole this rate is achieved, so what is causing the specific problem on Squam Lake? Loons, a long-lived species with a low reproductive rate, face many adverse conditions: climate change, lakeside development, chemical pollution, recreational boating, and ingestion of lead fishing tackle. The members of the Squam Lake Project have shown that chemical pollutants such as PCBs, flame and stain retardants and even DDT have entered the lake in at least three sites in the Northeast quadrant of the lake. These pollutants have been found in non-hatched eggs and may well have contributed to the reproductive failure. As fat-soluble pollutants, they enter the adults’ fat stores and are released in toxic amounts during the energy-intensive migration and molt. However, the most important finding is that adult loons are ingesting lead jigs and sinkers during the fishing season. The loon’s gizzard produces lead plumes that enter the blood stream and brain, killing the bird in short order. Because the demographic profile is so dependent on maintaining the cohort of adults, this mortality is disastrous for a stable population. New Hampshire has enacted strict lead fishing tackle legislation over the objections of a vocal minority, but compliance is still an issue. The Squam Lake Project has initiated a lead tackle buy-back scheme, which it is hoped will help to alleviate this problem. One further aspect that the group is examining concerns loon social behavior. When new-comers arrive on the lake to replace missing adult loons, significant fighting occurs over optimal nesting territories. This “social chaos” may also contribute to reproductive failure. The Squam Lake Project is hopeful that with greater understanding by the public of the loon’s importance as an indicator of the ecological health of the lake, this iconic species will continue to delight generations to come.
At 7:29 p.m. President Saunders reconvened the meeting. Recording Secretary Hamish Young read the Minutes of the February 8th 2019 meeting. They were approved as read. President Saunders congratulated the winners of the Silent Auction at the Annual Dinner and thanked Officers and Members of the Council for their work during the past year. Nominating Committee Chair Richard Lieberman announced the names of the new nominations for Council Membership proposed by the nominating committee Elise Boeger, Nancy O’Keefe and himself: Kathleen Matthews to serve until 2020, and Sherry Felix, Mary Jane Kaplan and Bruce Yolton to serve until 2022. The nominations were approved unanimously. Secretary Lydia Thomas announced five new candidates for membership: Gail Hashimoto and Renee Lucier sponsored by Gabriel Willow, Susan Freytes sponsored by Mary Beth Kooper, Sandford Sorkin sponsored by Rick Wright, and Ryan Zucker sponsored by the Society’s Council. The nominations were approved unanimously. President Saunders announced the dates of the Great Gull Island Birdathon on May 11th and 12th, and the Spring Cleanup at Plumb Beach on April 29thsponsored jointly by the Society, New York Audubon and the Wild Bird Fund. Past President Andrew Rubenfeld announced that the 76th Proceedings of the Society were available at the front of the auditorium to all members, free of charge upon signing. He observed that spring migration was well under way, with the usual species appearing on time.
After the conclusion of the business section of the meeting, President Saunders introduced Douglas Futuyma, Distinguished Professor Emeritus, SUNY Stony Brook and Linnaean Society Member. His talk, “World Birding: Travels and Reflections of an Evolutionary Biologist,” detailed how an appreciation of birds and their behavior prompts evolutionary questions that illustrate the twin Darwinian principles of descent from a common ancestor and adaptation by natural selection. Using a wealth of examples, primarily from the avian world he has encountered on his travels, Douglas began by describing the nesting behavior of the Malleefowl, an Australian Megapode. The male builds a large nest on the ground that he attends twice a day for eleven months. During that time, females lay their eggs in the nest and these eggs are incubated without direct contact with either parent. The male keeps the temperature correct for incubation by adding or subtracting dirt and decomposing leaves. Upon hatching, the young are able to leave the nest directly for independent lives. Is this unusual life cycle, reminiscent of reptilian nesting behavior, a relic of common ancestry with the nearest reptilian lineage, the Crocodilians? Molecular phylogenetic studies rule this out, as Megapodes diverged after several other avian lineages. It seems more likely that Megapodes have adopted the reptilian-like nesting behavior independently, as a later adaptation. Modern phylogeny has also contributed an answer to the riddle of disjunct distributions in the avifauna. For example, the Trogons and Broadbills are found in South America, Equatorial Africa, and Southeast Asia, with no relatives in intervening geographical areas. Could this reflect the break-up of the ancient southern supercontinent of Gondwana? Phylogenetic analysis rules this out, as both families evolved later than the breakup of Gondwana. A more plausible scenario is that the ancestors of both groups had a worldwide distribution, but the species in the intervening areas have become extinct. Turning to Darwin’s mechanism of evolution, natural selection, Douglas described work on the Galapagos finches showing changes in bill size occurring within short periods of time, under changing environmental conditions. He also described color and behavioral dimorphism in several species of birds including the two color-morphs in the White-throated Sparrow. White morphs of both sexes are more aggressive, but tan morphs are better parents. This difference is accounted for by different locations of the hormone receptor ERalpha in the brain. Breeding pairs are made up of one white parent and one tan parent, thus harnessing the advantages of both behaviors. Moreover, the behavioral and the anatomic traits are kept together by a genetic trick, a chromosomal inversion encompassing the genes for both traits, thus preventing them from being separated during the production of new gametes. In concluding, Douglas noted that the appreciation of the aesthetic qualities of birds and the scientific evaluation of their adaptations go hand in hand, the former prompting questions and the latter attempting to find answers.
The meeting was adjourned at 8:58 pm.
Respectfully submitted by
Hamish Young, Recording Secretary