More US bird populations are reaching their ‘tipping point.’ Some of the species may come as a surprise.

More than half of bird populations are sharply declining across the United States, and dozens have been added as tipping point species — but species like swans and geese are doing fine.

Tipping point species are close to threatened or endangered status because they have lost half or more of their populations in the last 50 years. The State of the Birds Report, by the North American Bird Conservation Initiative, used five different sources of data, including the North American Breeding Bird Survey and the Audubon Christmas Bird Count.

Everyone needs to begin thinking about conserving common species before they become uncommon, said Nick Flanders, an officer at the Cape Henry Audubon Society, a local chapter of the National Audubon Society located in Norfolk. Part of this is looking at if they need a specific habitat to flourish and protecting that space because building populations back is more difficult than maintaining them.

“It is a little bit harder to get people excited about protecting a rare species of grass to help that habitat for a bird species,” Flanders said. “So if you are interested in protecting that bird species people are interested in, that works a lot better.”

Maintaining bird populations also helps preserve other plants and animal populations in the different ecosystems and keep those environments healthy. One way to do this is by protecting the other parts of the ecosystem, not just the birds.

Some of the birds on the list may come as a surprise. A trip to the beach comes with a myriad of sounds, including the relentless squawk of seagulls and their seemingly endless invasions to steal snacks from beachgoers. The Heermann’s gull, a species within the broader seagull group, has lost half its population over the last 50 years and is on track to lose another half of its remaining population over the coming 50 years.

Issues like habitat decline and an increasingly limited food supply from natural sources add to the dramatic population loss of the gulls. According to the report, more than 60% of seabird species were found to have eaten plastic, and 40% have been tangled up in the waste such as spent fishing nets.

Other seabirds, including two different kinds of albatross, petrels and the red-faced cormorant, made the tipping point list.

The report also lists many wetland birds. Flanders said factors like sea-level rise will create conservation challenges in helping the different species.

“The marsh only has a small threshold before flooding, and especially when there is a development behind it, like houses, the birds don’t really have anywhere to go,” Flanders said.

Species like the salt marsh sparrow that lay their eggs in the marshes are vulnerable and have lost about 9% of their population per year since the 1990s. The population could collapse in the next 50 years if nothing is done, according to the Atlantic Coast Joint Venture, a conservation organization. Frequent and more intense nest flooding due to sea level rise is currently the greatest threat to this species.

Although there are significant losses, it is not all doom-and-gloom.

The decline of Eastern forest birds has slowed over the last decade, according to the report. The cerulean warbler and the wood thrush showed about a 60% decline since 1970, but their populations are not dwindling as fast. The wood thrush population even recently saw a slight increase of a little over a half percent.

The Appalachian Mountains Joint Venture, a partnership of over 50 federal, state and nonprofit organizations, has made large contributions in habitat restoration. In 2020, AMJV restored more than 8,700 acres of habitat on private land between West Virginia, Maryland and Pennsylvania. Some of the largest population increases came from these improved areas.

Some of the forested species listed in the report appear to be doing well in Hampton Roads, such as the prairie warbler, Flanders said. The Great Dismal Swamp, among other preserves, is a haven for the warblers, and they are common during the breeding season — which is why Flanders was initially surprised upon reading their name on the list.

“But, if you think about the areas away from these protected areas, with the development and loss of forested area, some of these declines do make more sense,” he said.

Waterfowl like geese, who are seeing record high populations, have adapted from habitat loss and began to use areas like farmland to live. There have also been local and federal conservation efforts to protect waterfowl populations. The North American Wetlands Conservation Act and U.S. Farm Bill conservation programs are two examples that provide incentives for farmers to improve habitats, like wetlands, on their property.

Everett Eaton, 262-902-7896, everett.eaton@virginiamedia.com