Fundamental to avian science,
it helps protect
our planet.
By Peter McKenzie-Brown
I’ve been a birder
for most of my adult life, and it’s a splendid hobby. One of its great
pleasures is that it lures us into the natural world, where we train our
binoculars and ears on species of extraordinary beauty and often splendid song.
Besides birding as a hobby, in recent years, I have added the practice of bird
banding assistant to my birding activities. My friend Bill Taylor is the
certified bander, and on trips into rural Alberta I am often his helper. We are
among many volunteers who help band beautiful Mountain Bluebirds (photo, right) and Tree
Swallows at nest-boxes in the Alberta foothills.
The
backstory to our banding activity is the dramatic reductions in the populations
of numerous bird species because of changes in predation, farming, and forestry
practices. In Alberta, bird-loss led to the development of “Bluebird Trails” –
volunteer-built nesting boxes placed at intervals along highways and byways to
provide safe breeding sites for the Bluebirds. Opportunistic Tree Swallows,
which winter mostly in Mexico, also acquired a liking for these boxes. Through
regular visits during breeding season, we keep records of nesting successes and
band the nestlings, keeping detailed biometric info for the chicks. When we capture
adults, we band them, too.
Our efforts are a
miniscule part of a global effort to better understand our avian friends. We attach
bands on the baby birds’ legs when they are old enough 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.
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. Banding
practices around the world help our avian friends, but only because of the vast
international machine in which each bander is a tiny cog.
Banding requires armies
of volunteers – the heartbeat of “citizen science.” In Canada, 27 primary sites
– the Canadian Migration Monitoring Network - track birds during spring and
fall migration, using both observation and banding techniques. Many licensed
banders and other volunteers show up before dawn during migration, capturing specimens
in fine-meshed “mist nets” set up for the occasion. An example is Ontario’s
Long Point Observatory on Lake Erie, which began banding during migration in
1960. Seventeen years later, volunteers banded their millionth bird. These long-term,
continual records are vital to understanding changes in population and species
movement in our rapidly changing world.
We maintain the
boxes so we can keep records of nesting successes and failures. Licensed banders
like Bill clip a band on one leg of captured adults and mature nestlings. 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. When we
recapture banded birds, our reports to ornithological authority help avian
science gain a better understanding of the migration patterns, ages, and
changes in species behaviour over a well-defined period. The bands themselves
neither harm nor hamper the birds.
With the help the
banding armies, ornithologists long ago established that migratory birds need
intact habitats to survive. A few years ago, the Audubon Society (named after a
renowned 19th century ornithologist) published Survival by Degrees, a report showing that 64 per cent (389) of
North American species risk extinction from climate change. The good news was
that immediate action could improve the chances for three quarters of those species.
How does
banding protect birds?
Every time someone bands
a bird, the bander records the location, date, species, gender, estimated age,
and other features, and sends that information to the lab. To ensure the birds’
well-being, capture and banding are done by trained volunteers and researchers.
The USGS works with The North American Banding Council, which develops banding
materials and addresses safety regulations.
People who see or
catch a banded bird report that information back to the lab, which keeps
records of all reported encounters. Laboratory staffers manage more than 77
million archived banding records and more than 5 million bird encounter
reports, with an average of nearly 1.2 million banding records and 100,000 encounter
reports submitted each year.
Through banding
research, scientists can learn a bird’s routine, such as where they spend most
of the day, where they migrate, what they eat and how much habitat they need to
feed and reproduce. This information can help identify priority areas for
conservation.
Banding data can
reveal other trends in life span and population. If there is a change in the
age of birds caught at a certain location, life expectancy may be getting
shorter or longer. The number of birds captured may indicate whether
populations are increasing or in decline. Data such as weight and wingspan can
show health trends. Such insight can cue scientists to look for changes to
birds’ food sources, predators, competitors, habitats, and other factors that
affect their survival and reproduction. Sampling wild birds for Lyme Disease and
Avian Influenza can help determine these diseases’ prevalence. Bird migration
routes can identify which human and animal communities are at risk of exposure
too. And toxicologists can determine the results of avian exposure to
contaminants and other environmental threats.
Banding is by no
means a recent practice. Two
years ago, the US Geological Survey wrote a celebratory article about banding’s first century in North
America. Birders are among the multitudes who know that most birds bring joy
merely by their presence – from their bold colours and majestic songs to their
grace as they glide flap or glide through the sky. But they contribute more
than beauty. Many plants depend on hummingbirds and other species to pollinate
them. Hawks and owls target rodents and other pests. Fruit- and grain-eating
birds help spread the seeds of the plants they consume.
Some bird researchers
add additional markers to identify individuals in the field without the need to
recapture them. Some colour and alphanumeric code combinations can be read from
a distance with binoculars or spotting scopes. Different types of markers are
used depending on the type of bird, its behaviour and the information needed.
Bands weigh only a small fraction of a bird’s weight so as not to impede
movement and researchers must follow strict protocols that have been tested and
revised over the years to reduce any potential harm or hindrance to the birds.
A small metal band
with a unique number is placed on a bird’s leg so that when its band is
reported its movements can be reconstructed. Birds may carry other markers.
These include neck collars, used to mark geese and swans, which are readable
from a distance with binoculars or a spotting scope. Wing markers on vultures,
eagles, swans, ravens, crows, or herons are often visible while the birds are
in flight or perched. Leg flags on shorebirds stick out from the upper leg with
a code which can be read from a distance. These bands can indicate, for instance,
that the birds wearing them belong to a specific location or banding project.
As a scientific
technique, banding requires expertise and skill usually gained over many years
of study and field experience. To participate in banding
activities, you must apply for a Scientific Permit to Capture and Band
Migratory Birds. Generally, people with banding permits are professional ornithologists,
biologists, wildlife technicians. Many are retirees who just want to help.
A Canadian Bird
Banding Office (BBO) in Ottawa issues permits to capture and band within Canada.
Banders from other countries who want to band here must first receive a permit.
Jointly administered by Canada's BBO and
America’s Bird Banding Laboratory, this program relies on the public to
report their observations or recoveries of bird bands and other bird markers.
This data helps scientists and researchers understand, monitor and conserve
migratory birds. We also track and publish longevity records for each North
American bird species.
Birds are also good
indicators of environmental health because they are sensitive to habitat
change. Changes in bird populations can indicate environmental stressors, such
as impacts from extreme weather or human development, which could affect other
parts of the ecosystem. For these reasons and others, researchers conduct avian
conservation science.
Because the U.S.
and Canada coordinate their banding work through the North American Bird
Banding program, which links the Canadian Wildlife Service Bird Banding Office
with America’s labs. These organizations cooperate closely – especially on
species that migrate within and through North America. However, birds are
banded across the world, and both Canada and the US collaborate with other
countries. 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.
How to sum up? For me and certainly most other birders, one of the great pleasures of birding is that birds lure us out of our homes into the natural world. Helping to band is an enhancement to that marvelous experience.