Wildlife population experts are sounding the alarm that North America has nearly 3 billion fewer birds now than in did in the 1970s.

It's meant losses in Washington state, too.

Birds that live in Washington's forests and coasts are under particular threat, according to a study in the journal Science this month, which was based on radar networks and human monitoring of bird populations and migration since 1970. It shows nearly every bird species in decline.

Dr. Nicole Michel with the National Audubon Society contributed to the study. She said in the Pacific Northwest, "species we're seeing particularly strong declines in [are] forest birds, with 30 percent decline, and coastal birds [such as] sand pipers and clovers."

Others include bald eagles, marbled murrelets, spotted owls, and yellow-billed cuckoos. There are 33 birds listed as endangered, threatened, or a species of concerning species in Washington state (you can search the list here).

The scientific report notes that the overwhelming focus on animal extinctions has led people to underestimate the extent of biotic change and ignore the declining numbers of still-common species.