Besieged by commercial hunting, habitat loss and a host of other ills, migratory birds in the late 1800s and early 1900s in the U.S. and Canada were in steep declines.
Perhaps most famously was the case of the passenger pigeon, noted Glacier National Park biologist Lisa Bate. The pigeon once numbered in the billions in the eastern U.S. But wholesale hunting, a low reproduction rate (the birds only laid one egg per nesting season) spelled doom for the species. By 1914, Martha, the last passenger pigeon left in the world, died in captivity.
She lived 29 years, but never laid a fertile egg.
But in 1918 Congress signed the Migratory Bird Act, which, simply put, protected birds. More specifically, it made it “unlawful to pursue, hunt, take, capture, kill, possess, sell, purchase, barter, import, export, or transport any migratory bird, or any part, nest, or egg or any such bird, unless authorized under a permit issued by the Secretary of the Interior.” The Act codified an earlier treaty with Canada. It does allow for some hunting — there are still seasons, for example, of ducks and geese.
Being the 100th anniversary of the Act, National Geographic, the Audubon Society and 200 other organizations, including the National Park Service, have declared 2018 the “Year of the Bird” Bate noted.
Since its passage, the Act has been instrumental in the recovery of bird species that were in danger of extinction. The snowy egret, for example, was nearly hunted to oblivion because its feathers were used in women’s hats.
On a local level, Glacier has a host of migratory birds, in fact, most of its known species don’t spend the entire year in the Park. The Park has 276 species that have been recorded in Glacier and the list will soon add two more — the barn owl and the magnolia warbler have both been recently recorded in the Park, Bate said.
It is also home to several rare species.
The Black Swift is of particular interest. The swift is an odd bird. It winters in the Amazon and nests in the northern U.S. and Canada. But while most birds are done nesting by July, the Swift is just arriving and its young don’t fledge until late August or early September. It also only makes its nest behind active waterfalls and only lays one egg.
It spends its days hunting insects and only comes back to the nest at dusk. Recent surveys have found 35 black swifts in Montana — 25 of them are in Glacier, Bate noted.
But the birds are susceptible to climate change — waterfalls require water, and Glacier is becoming a warmer and drier place in the summer, particularly in late summer when the birds are actively nesting. By then, even some of Glacier’s most robust waterfalls can be reduced to a trickle.
In Canada, the species has already been listed as endangered.
Glacier also has other species of concern, notably harlequin ducks, common loons and golden eagles. The Park keeps close tabs on all three species and this year it plans on formally having a “hawk watch” station this fall on the flanks of Mount Brown to count migrating birds of prey as they fly through the Park.
Golden eagles have seen steep declines nationwide in recent years. They face a host of issues — from collisions with wind mills to non-native cheat grass. Cheat grass is a non-native weed that can overtake fields in eastern Montana. As a result, there’s fewer jack rabbits — a main source of prey for the birds. The eagles also suffer from lead poisoning by eating carcasses of animals that are wounded, but not recovered by hunters that later die.
Poaching is also a concern.
“There is still the thought that any raptor is bad ... ‘it might eat my chickens.’” some folks say, Bate noted.
In Glacier, historically there were 44 known golden eagle nesting sites. Today there are only seven.
But there are some bright spots in the birds of the Park. While harlequin duck populations are on the decline across the west, their populations are holding their own in the Park.
More research on harlequins and their movements is planned for this year. The duck is odd in that it migrates from east to west and only nests in the drainage where it was hatched. Harlequins primarily winter on the west coast in the ocean, but one male was noted in the east recently — a bird banded in Glacier was spotted on Lake Erie, one of the Great Lakes.
The birds then return to Glacier and the mountain west to breed. They’re particularly a common sight in the early spring along upper McDonald Creek.
All is not well in the bird world. The Washington Post last week reported that the Trump administration had reinterpreted the Migratory Bird Act.
Under the new interpretation, companies that kill birds in events like oil spills, wouldn’t be held liable. The Post story indicates the backlash against the Act comes after a North Dakota oil company, whose owner has ties to President Trump, was pursued by federal prosecutors because it didn’t cover its waste oil pits with netting to keep birds out.
The birds were landing in the waste oil pits and dying.