Zaps are notes of awareness and pleas for action that appear in the corresponding print edition of Bird Observer. Here they are from the current issue.
February 1, 2022
2 MIN READ
Zaps
The Pecking Order at your Feeders
Birding Community E-Bulletin, December 2021
Supplied with a wonderful database of almost 100,000 bird interactions, the gang at the Cornell Lab of Ornithology’s “Project FeederWatch” announced the decoding – a virtual pecking order – of feeder-visitors. This power-ranking, covering scores of species, made something of a splash last month, and the listing wasn’t always related to a size-order as expected.
Yes, the grouping and chart-display did start with the hefty Wild Turkey at the top, and it ended with the small and retiring Brown Creeper toward the bottom, but a size-hierarchy wasn’t always the rule. For example, Mourning Doves might outweigh other species, but they also give way to smaller species. Woodpeckers are tough – they peck after all – but the large Pileated Woodpecker also proves to be fairly docile.
Some bird rivalries at the feeder are too complex for a simple ranking. The House Finch usually dominates the Purple Finch, and the Purple Finch almost always dominates the Dark-eyed Junco. But when the House Finch and Dark-eyed Junco face off, the latter often dominates.
The most complex relationships are probably between American Goldfinches and the closely-related Pine Siskin. When these species show up – usually in flocks – they appear to get into serious squabbles both among themselves and with almost every other species.
Since 1987, thousands of backyard feeder-watchers across the U.S. and Canada have participated in Project FeederWatch, a project jointly run by the Cornell Lab of Ornithology and Birds Canada. And since 2016, observers have been able to report specific bird power-interactions.
“The birds are at a food source, so it’s a place where they’re more concentrated and even more likely than usual to have these behavioral interactions,” said Project FeederWatch leader Emma Greig.
In a 2017 study in Behavioral Ecology, Project FeederWatch researchers applied the first wave of their data into algorithms to condense the complex of relationships into a simple rank. Since the project had a network of 30,000 citizen-scientists, this meant the team could collect data at a continental scale. And now, a vastly expanded data set of 99,376 interactions among almost 200 species, up from 7,685 interactions in the 2017 study, is able to provide more serious findings.
For some of us, especially those with some bird-banding experience, it was a surprise to find that chickadees – both Black-capped and Carolina – often perceived to be quite feisty, were actually the least dominant of the more common feeder-birds.
For more see: https://www.washingtonpost.com/business/2021/11/28/bird-feeder-pecking-order/
https://www.cbc.ca/radio/asithappens/as-it-happens-tuesday-edition-1.6268087/when-it-comes-to-bird-feeders-there-s-a-pecking-order-and-size-really-matters-1.6268088
Birding Community E-Bulletin Archive: https://www.refugeassociation.org/birding-community-e-bulletin/