The Loss of Bird Species

 

This is for the Birds

By Peter McKenzie-Brown

What, exactly, is Canada’s biggest export to America? An economist would put crude oil, cars, unwrought gold and automobile parts and accessories as the big four. A naturalist would say, “Birds.”

On this continent, at least, the most prominent naturalist John James Audubon (1785 -1851) was an American ornithologist, naturalist, and painter. His combined interests in art and ornithology turned into a plan to make a complete visual record of North America’s.  He was notable for his extensive studies documenting all types of American birds and for his detailed illustrations that depicted the birds in their natural habitats. His major work, a colour-plate book entitled The Birds of America (1827–1839), is considered one of the finest ornithological works ever. Audubon is also known for having identified 25 new species. He is the namesake of America’s National Audubon Society, and the scientific community still uses dozens of words he first published. What he probably could not have imagined is that the career he developed into two ground-breaking books would, in more prosperous times, become a widespread hobby.

For birders (“bird watchers,” to the uninitiated), one of the great pleasures of this hobby is that it lures us into the natural world. My wife Bernie and I have been birders for nearly 25 years. We learned that 914 avian species occur naturally north of the US/Mexican border, and that 426 species make their way to Canada. In those years we have identified more than a thousand species – across Canada in Europe and in Southeast Asia. And as our interest grew,a friend acquainted us with the practice of bird banding. We are among many volunteers who help him band beautiful Mountain Bluebirds and Tree Swallows, which breed in the Alberta foothills. Both species winter in the southern USA and northern Mexico.

There were dramatic reductions in the populations of these (and other species) during the mid-20^th Century because of changes in predation, farming, and forestry practices, and competition from such introduced species as the European Starling. This led to the development of “Bluebird Trails” – volunteer-made nesting boxes placed at intervals along highways and byways to provide safe breeding sites. Opportunistic Tree Swallows, which spend their winters even further south in Mexico, soon acquired a liking for these nesting boxes.

Volunteers maintain the boxes, keep records of nesting successes, and – if they are licensed to do so – band the birds. Our efforts are a miniscule part of a global effort to better understand our avian friends. We attach bands on the legs of the young just before they are about to leave the nest box. We also band adults we capture in the nest. If banded birds are ever recaptured, or if someone finds a band on their legs after they die, the ornithological community gains a better understanding of their migration patterns and changes in their behaviour over a well-defined period. The bands themselves neither harm nor hamper the birds.

The practice of bird banding is a logical continuation of birdwatching. It reflects the simple reality that people need nature to be happy – and little in nature is lovelier than birds and birdsong in the wild. Bird banding is a remarkable example of citizen science. It involves the efforts of large numbers of volunteers to help keep track of the movements of individual birds and their life histories. Banders and their assistants tend to be retired women and men, in roughly equal numbers.

In Canada, 27 primary sites (the Canadian Migration Monitoring Network) track the movement of birds during spring and fall migration, primarily using both observation and banding techniques. Licensed banders and volunteers are afield before dawn during the migration seasons. They capture birds mainly by erecting fine-meshed nets in areas of known bird movement. They sex, age, weigh and measure the birds, making assessments of each bird’s health as they band it; this link provides recent information about the Calgary-area organization.

At many of the primary sites in Canada, birds have been banded for many years. The Long Point Observatory on Lake Erie in Ontario began banding in 1960. Forty-seven years later, volunteers there banded their millionth bird. The long-term, continuous records from these sites help ornithology vital to understanding changes in population and species movement in our rapidly changing world. These studies demonstrate clearly that many migrant species are declining in numbers – vulnerable on their breeding grounds, their wintering grounds, and along migratory routes.

Bird banding involves attaching a small, individually numbered aluminum or coloured plastic tag to the leg of a wild bird prior to its release. These data are maintained in a central depository, available online. If you recapture a banded bird in Canada or find one dead, report its band number, date and location to this address; in the US, report the information here.

Technical Advances

Most birds are migratory, and the North American Migratory Bird Treaty recognizes that the countries through which they travel on these migrations need to protect them.

During the chaos of World War I, US President Woodrow Wilson and King George V of Great Britain signed the Migratory Bird Treaty Act in 1916.; two years later, the US passed the Migratory Bird Treaty Act – legislation which protects more than 1,100 migratory bird species by making it illegal to “pursue, hunt, take, capture, kill or sell live or dead birds, feathers, eggs and nests,” except as allowed by permit. Most species of birds in Canada are protected under the Migratory Birds Convention Act, 1994 – passed in 1917, and updated in 1994 and 2005. This act gives the Canadian federal government the authority to pass and enforce regulations to protect those species included in the Convention. Similar legislation in America protects species found in that country, though the list of bird species protected by each country can be different. Canada’s 1994 update kept the legislation consistent with US standards.

One result was a far greater understanding of bird migration patterns. For example, in the 1930s, an American researcher established that North American birds migrate within the continent through four predictable corridors. It also became clear that billions of birds migrate from North America’s Arctic tundra and boreal forest, most of which is in Canada. A strengthened scientific consensus led to growing efforts to protect boreal lakes and forests, which constitute our biggest hatchery.

Recent technological developments are helping uncover the mysteries of bird migration, yielding detailed data about the hemispheric-scale movements of migratory birds. Most importantly, these systems provide information about what we can do to better protect birds, using increasingly sophisticated technology. For example, satellite tracking and geolocation devices provide detailed accounts of when and where birds move, and the places where they stop. This reveals areas where habitat protection is critical. Compared to banding, however, geo-tracking is an expensive way to obtain data.

Perhaps the most important recent advancement is the development of eBird by Cornell University. This program allows birders everywhere to submit their sightings and counts to a central data base. As usage expands and the software becomes more sophisticated, greater understanding of the size and distribution of bird populations is developing, both historically and in real time. Anyone interested in birds and in helping to ensure the continued survival of these species can sign up and submit their sightings to the database.

For bird banders, a computer program named Bandit is the latest in a series of desktop applications aimed at helping them manage and submit their data for banded birds. Its use makes maintaining banding records much simpler. Banders use the no-charge software to store data obtained during banding operations. At the end of the season, Canadian banders use it to transfer their data to an Ottawa agency, which shares it with its US counterpart.

How the Environmental Crisis Threatens our Birds

We must never become complacent about the survival of birds. The Passenger Pigeon was the most abundant bird in North America in the early 19th Century, with a population of perhaps 5 billion birds. From the early 1800s to the 1890s, most of the birds were shot both for food and entertainment. “Martha,” the last of her species, died in captivity in the Cincinnati Zoo on September 1, 1914.

The efforts of this continent’s ornithologists, with the help of an army of banders and other enthusiasts, long ago established that migratory birds need intact habitats – vast in extent – to survive in our natural world. These habitats range from breeding areas (mainly in the north), to wintering ranges, with innumerable habitats in between. Each year, the continent’s Arctic tundra, its boreal forests, and other environments the north to export three to five billion birds to winter ecosystems of the Americas, in southern Canada, the 48 contiguous states and, for some species, Mexico, the Caribbean and South America.

A recently released scientific report, Survival by Degrees, shows that 64 percent (389/604) of North American bird species are at risk of extinction from climate change. The good news, the report says, is that immediate action can improve the chances for 76 percent of the threatened species. Centuries of bird science show what we can do to protect the birds we love and the wilderness areas we need now and will continue to need. To do nothing to protect our birds and their habitats would be enough to make a birder cry.