You do what to those pretty
little creatures?! Why?
By Peter McKenzie-Brown
Over the course of a normal year, 914 species of wild bird occur naturally north of the US/Mexican border. Of these, 426 species reside in Canada. For me and probably many other birders (the uninitiated call us “birdwatchers”), one of the great pleasures of this hobby is that birds lure us out of our homes into the natural world.
Blue Bird eggs... |
...and hatchlings |
There were dramatic reductions in the
populations of these (and many other species) during the mid-20th
Century because of changes in predation, farming and forestry practices, and
competition from other species, notably the European Starling. This led to the
development of “Bluebird Trails” – volunteer-made nesting boxes placed at
intervals along highways and byways to provide relatively safe breeding sites
for the Bluebirds. 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 in many cases also
band the birds.
Our efforts are a miniscule part of
a global effort to better understand our avian friends. We attach bands on the
baby birds’ legs just before they are about to leave their nest box, or, on an
adult if we capture it 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 of time. .
Banding
is by no means a recent practice. In 2022, the US Geological Survey wrote a celebratory article about
the first century of the practice in North America.
For hobbyists like me, 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. For the nations of the Americas, they are a shared
resource. Tragically, in my view, many millions of songbirds and others are at
risk because of recent political developments south of Canada’s border. More on
that, later.
Citizen Science
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, twenty-seven 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 their volunteer assistants 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 them, and make general assessments of each bird’s health as they band
it.
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. On 29th May, 2017, volunteers at that
site banded their one millionth bird. These long-term, continuous records are
vital to understanding changes in population and species movement in our
rapidly changing world. The findings of these studies demonstrate clearly that
many migrant species are declining in numbers. They are vulnerable on their
breeding grounds, their wintering grounds, and throughout their migration
route.
Bird banding involves attaching a
small, individually numbered \aluminum or coloured plastic tag to the leg of a
wild bird prior to its release. This data is maintained in a central depository,
available online. If you find a banded bird, dead or alive, report the band
number, date and location to
https://www.canada.ca/en/environment-climate-change/services/bird-banding/how-to-report.html
or, in the US,
https://www.fws.gov/birds/surveys-and-data/bird-banding/reporting-banded-birds.php.
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.
Signed into law amid 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. The 100th anniversary of this event,
which the two countries celebrated in Ottawa, was just two years ago. In 1918,
the US passed the Migratory Bird Treaty Act – legislation which protected 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. When Canada updated the Migratory Birds Convention Act in
1994, we kept the legislation consistent with what was, at that time, still US
standards.
The 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 technologies provide information about what we can do to better protect
birds, using increasingly sophisticated approaches in keeping with advancing
technology. For example, satellite tracking and geolocation technologies now
provide detailed accounts of when and where birds move, and the places they
stop in between. This reveals areas where habitat protection is critical.
Compared to banding, however, geo-tracking is an expensive way to obtain data.
The enormous strides in genetic
analysis in recent decades are rapidly changing our understanding of breeding
populations. Many species are now being split into subspecies as a result of
such data. Some species are being assigned to different families as greater
understanding of DNA helps us to understand their evolution.
Perhaps the most important
advancement is the recent development of eBird by Cornell University. This
program allows citizens, anywhere on earth, to submit bird sightings to a
central data base. As it expands and software becomes more sophisticated, many
different studies can be made of the size and distribution of bird populations,
both historically and in real time. Anyone interested in birds and in helping
to ensure the continued survival of these species should use this data (www.ebird.org)
and submit their sightings to the database. You can download apps from the site
without charge.
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 the American agency.
Are Politics now Failing 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 for food or as entertainment.
“Martha,” the last Passenger Pigeon, died in captivity in the Cincinnati Zoo on
September 1, 1914.
Politics are hardly new to the
birding community. Recently, for example, there has been controversy
about designating the Canada Jay (also called the Grey Jay) as Canada’s
national bird. In the United States, the Bald Eagle’s status as national bird dates
back to 1782.
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
Canada), to their wintering ranges, with innumerable habitats in between –
especially in and around wetlands. Between them, the Arctic tundra and the
boreal forest annually export somewhere between three billion and five billion
birds to populate the winter ecosystems of the Americas, from southern Canada
and the contiguous American states, into Mexico, the Caribbean and Central and
South America.
Despite the efforts of the birding
community, critical nesting grounds have long been at risk, mainly due to
increasing development pressures and climate change. These likely unstoppable
problems in recent years encountered another threat. This originated with the
recent reinterpretation of the Migratory Bird Treaty Act by America’s Interior
Department. As a result, the US President has signed a decree which, to large
degree, guts this policy.
America’s Interior Department
issued a legal opinion that reinterpreted the act to exclude “incidental take.”
For example, previously the interpretation argued that fear of “unlimited
potential for criminal prosecution” strongly encouraged cat owners from letting
their pets attack migratory birds. Similarly, drivers who accidentally killed
birds with their cars might be charged with crimes. In practice, the act had
never been enforced in that way. It was applied to cases of gross negligence
where potential harm should have been anticipated and avoided, such as
discharging toxic pesticide contaminated water into ponds used by migratory
birds.
In her commentary on the recent
reinterpretation of the act, Professor Amanda Rodewald – she serves as director of conservation
science in Cornell University’s ornithology department –suggested that
industry will be the primary beneficiary of this new interpretation. In her
view, “This new reading of the law means” that “corporations and others who
fill in wetlands will escape liability for actions that could kill millions of
birds every year.”
It’s more than enough to make a
birder cry.
Author’s
note: Thanks to Dave Russum, Bill Taylor and Gus Yaki for their comments on
this article.
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