MARS Moment 2012
by Sandy Fairfield, MARS Education Coordinator
Once hunted for their feathers and hides that were prized for hats, boas and other fashionable goods, they also provided valuable food. The Migratory Bird Act was put into place in 1918 which put an end to swan hunting; in 1932 their numbers were reduced to a mere 69 birds. As a result of the restrictions of swan hunting, their numbers have continued to improve and in 2008 populations were estimated to be at 16,000. Last year between December 6th and February 24th an average of 2,300 swans were counted on a weekly basis by the Comox Valley Naturalists swan monitors. This society has been monitoring the swans with a weekly count every Tuesday, as part of the Comox Valley Waterfowl Management Program to manage the swans on local farmland. According to the Naturalists, swans can rival the cows for daily food consumption on farm lands. The West Coast winter swan habitat ranges from Sumas and North West Washington and BC, including Vancouver, as well as the east coasts of central and southern Vancouver Island. Northern B.C. and Alaska provide their breeding and summer habitat.
During their winter stay in the Comox Valley and parts of Campbell River, Trumpeter Swans dine on a variety of field crops including, hay, corn, perennial grasses, seeds and tubers including marsh and wetland vegetation. Habitats for our local swan populations include agricultural farm lands, wetlands and estuaries, also the shallow waters around the Goose Spit. Arriving at their winter grounds with the young juveniles, the swans have only at few short months to prepare and be in top flying condition to make the arduous spring migration back to the far north. Often when the swans arrive in Alaska and other northern grounds they are faced with frozen water and snow still on the ground, this makes their need to breed even more urgent as they have to build their nest, produce their eggs, and hatch their young. Nests are freshly built or old nests reused, and are often found on vegetation in shallow water; hatching of the cygnets coincides with the explosion of the insect population upon which the young feed for the first few weeks of their life. There are many predators for the young swans, including eagles, owls and mink, but there are also many other dangers as they fly south and arrive in our area. Like all wildlife, human impact is the greatest peril facing the swans, as our habitat continues to encroach upon theirs, each year another potential hazard arises as it appears they will be at greater risk for any oil spills or other water pollutants with the proposed expansion of pipelines.
Migration takes a huge toll on the young if they run out of stored fat supplies; we often see them at M.A.R.S. emaciated and in need of a short stay to fatten them up so they can be released back to the flock. We have a special secure swan pond enclosure where swans are kept until they are ready for release, they are able to preen and clean themselves. In 2011 we had few swans in care, but 2012 saw five swans, including one Tundra Swan. The Trumpeter Swans huge wingspan sometimes makes them victims of electrocution by high wires, as often they are disoriented by fog and do not get enough height to clear the wires. We thank B.C. Hydro for helping with this issue by adjusting wires for both swans and eagles. Another hazard presents itself under the water when the swans forage for roots, in some areas left over lead lurks in the mud from old hunting practices and the swans ingest the poison into the gizzard, which it paralyses, causing fatal starvation. This is easy to identify as the swan “spins” in the water before drowning. You can also help by keeping dogs on a leash and away from the water’s edge when there are swans or sea birds close to shore. The Comox Valley is a major winter destination for migratory birds that dine on our abundant food supplies and we need to protect this habitat.
For more information, The Comox Valley Naturalists also have a web site www.comoxvalleynaturalist.bc.ca . They also conduct monthly meetings. To report injured wildlife please call MARS toll free 1-800-304-9968.