Decline of Common Loon in Shoal Harbour Migratory Bird Sanctuary

Common loon by Andrew Reding via Flickr
In a special guest post, Kerry Finley (also known as James Finley), Important Bird Area Caretaker for the Sidney Channel IBA and Coastal Waterbird Survey Volunteer, shares his observations of an iconic Canadian bird. As an IBA Caretaker, James is the eyes, ears and feet on the ground at his IBA. Nature Canada and Bird Studies Canada co-deliver BirdLife’s IBA Program in Canada.
Coastal areas of British Columbia are recognized for their regional and international importance for numerous migratory waterbirds, including various loon, grebe, cormorant, heron, duck, gull, tern and seabird species. During the winter, waterbirds are attracted to BC’s relatively moderate climate, extensive estuaries, tidal flats, and near-shore protected habitats. Shoal Harbour Migratory Bird Sanctuary and the adjacent Sidney Channel Important Bird Area support a diversity of habitats and migratory birds. These species are dependent on the ecological processes that support a diversity of forage fishes and invertebrates.
The Common Loon is a consummate fisher, highly dependent on various small fish species. Its presence and abundance is a good reflection of the health of the marine ecosystem. The results of 79 monthly waterbird counts at Roberts Bay, which is part of Shoal Harbour Sanctuary in the southern Salish Sea, show a long term decline of this species. Last winter, for the first time, not a single loon was detected during the surveys, and except for two observed in September 2010, none were seen during casual daily observations in the sanctuary.
At one time Common Loons were observed every day in the sanctuary. These observations suggest that something drastic has happened to the ecosystem affecting their fish prey. The Pacific Loon and the Red-throated Loon have also declined in abundance at this site, as well as the Horned Grebe, the Red-necked Grebe and the Western Grebe which are all piscivores, or fish eating birds.
After several years of surveying the same site, Coastal Waterbird Volunteers become very familiar with the seasonal patterns in bird abundance and distribution at their site, noticing yearly differences which can be useful to track over time. Coastal Waterbird data is available to any volunteer to download for their site, or any of the sites, through Nature Counts at www.naturecounts.ca.As the national sponsor of the Important Bird Area Caretaker Network, TransCanada Corporation committed $1 million in 2009 to support bird conservation efforts in Canada over the following five years.

Watch an interview with Kerry at the Shoal Harbour Migratory Bird Sanctuary.
This article first appeared in Bird Studies Canada’s December 2011 newsletter.