Photo: Songbird Decline, Chris Maynard
By Lisa Mackem
Wild bird populations in the continental US and Canada have declined by almost 30% since 1970, representing a loss of nearly 3 billion birds. This loss astounded Cornell Lab of Ornithology conservation scientist, Ken Rosenberg. Rosenberg led an international team of scientists from seven institutions in the analysis of population trends for 529 bird species. The journal Science published the study results in September.
The scale of loss is unlike anything recorded in modern natural history. It includes hundreds of bird species across the continent. The research confirming these losses represents the most robust synthesis of long-term population monitoring data ever assembled for animals, said Adam Smith, a study coauthor and biostatistician for Environment and Climate Change Canada. “It’s safe to say that in the natural world, birds are the best studied group of wildlife species,” Smith said. “The data that exist for birds are just so incredible, from 50 years of the North American Breeding Bird Survey and the Christmas Bird Counters from 100 years ago, on to the eBirders of today,” said Smith.
The study authors say that their work shows a pervasive loss in every North American biome. Forests have lost 1 billion birds and grasslands have lost 700 million, or 50% of their birds. The study authors identify habitat loss as a likely driving factor in these declines. More than 90% of the total bird losses (over 2.5 billion birds) come from 12 avian families, including common birds like sparrows, blackbirds, and finches. A Red-winged Blackbird was the subject of the winning 2019 Audubon photography contest photo. In the last 50 years, Red-winged Blackbirds lost 33% of their population – a severe and unsustainable loss.
Birds are indicator species, serving as acutely sensitive barometers of environmental health. Their mass declines signal that the earth’s biological systems are in trouble. Other studies have documented similar losses in populations of insects, amphibians, and fish. A 2019 United Nations report warned that approximately one million animal and plant species face extinction – more than ever before in human history.
Fortunately, there is also good news. North American duck and geese populations have grown by 56% since 1970, largely due to US and Canadian laws protecting wetlands and collaboration with Mexico to safeguard migrating waterfowl. Conservation management became increasingly science-driven. Private philanthropy, especially by Ducks Unlimited, generated significant financial support for wetlands acquisitions. Raptor and turkey populations also have been restored. A current bipartisan measure in the US House of Representatives – the Recovering America’s Wildlife Act – would direct $1.4 billion in federal dollars to invigorate underfunded state and tribal wildlife conservation programs. Bird populations that have suffered devastating losses have enough remaining birds to spur a recovery if conservation measures are implemented soon.
3 billion birds, co-sponsored by American Bird Conservancy, Audubon, Bird Conservancy of the Rockies, Georgetown University, The Cornell Lab of Ornithology, and Smithsonian National Zoological Park and Conservation Biology Institute published 7 Simple Steps to help birds:
1. Make windows safer
2. Keep cats indoor
3. Reduce lawn by planting native species
4. Avoid pesticides
5 Drink bird-friendly coffee
6. Reduce use of plastics
7. Participate in birdwatching citizen science.
Rosenberg warned that in 10 years, the current losses could be irreversible. The passenger pigeon was once the world’s most abundant bird, but people did not realize how quickly it was vanishing until it was too late. Meaningful action must start now.
You can participate in birdwatching citizen science by attending ASNV’s Project FeederWatch and Christmas Bird Count workshops this November – ASNV Workshops
Sources: https://www.allaboutbirds.org/vanishing-1-in-4-birds-gone/ https://www.nytimes.com/2019/09/19/opinion/crisis-birds-north-america.html https://science.sciencemag.org/content/366/6461/120