Barn swallows are birds with a long history of associating with people. They frequently make their mud nests under the eaves of houses, stables and barns. These summer visitors fly enormous distances from South America to raise chicks in Canada, then gather in chattering flocks on overhead wires before heading south again for the winter.
Shockingly, this once common and familiar bird has suffered drastic declines in population in recent decades. Since 1970, they have declined to less than a quarter of their previous number. The dramatic loss of these once common, artistically swooping, aerial insect-eaters, that brighten our countryside, is almost inexplicable. It should be a dire warning for the health of nature across the Americas.
The barn swallow statistic is just one of the conclusions in a seminal report on the “State of Canada’s Birds 2012”, a collaborative work by non-government groups and government agencies, under the umbrella of the North American Bird Conservation Initiative (NABCI). There are 451 bird species that regularly occur in Canada, and for those that have sufficient data to establish population trends, it was found that 44 percent of species have decreased, 23 percent show little change and a more fortunate 33 percent have increased.
The good news of increases occurs mainly among waterfowl and raptors. Waterfowl have seen very effective improvements in the management of hunting and habitat enhancement. Raptors (hawks, eagles and other birds of prey) benefited from the elimination of the pesticide DDT, leading to the return of iconic birds such as the peregrine falcon and bald eagle.
Birds which have experienced major declines belong to three groups: aerial insectivores, like swallows and flycatchers, shorebirds, and grassland birds. All of these tend to be long-distance migrants, which rely on stopover habitats en route between northern breeding grounds and southern wintering areas.
Aerial insect-eaters (or insectivores) have decreased more than any other group in Canada, with 22 out of 26 breeding species showing a decline, including swallows, swifts and nighthawks. While the cause is uncertain, and these birds pass through many countries before raising chicks in Canada, a few ideas spring to mind. How many people still pepper their yards with cosmetic pesticides hoping for the perfect lawn and disregarding the health of wildlife (and humans)? How often do people knock down an “untidy” swallow’s nest, believing it to be an eyesore on their property or some sort of health hazard, rather than an opportunity to raise a family of bug eaters?
Both these problems are easily addressed by home owners, and could make a big difference to these beneficial birds. A tougher situation is that of climate change, which may be causing a mismatch in the emergence of insects and the timing of seasonal cycles for birds, since even a week or two’s change in their synchronicity can lead to failed breeding success.
Shorebirds, that have some of the longest migration journeys of all the birds, have suffered an average 50 percent decline. Birds like the western sandpiper travel 11,000 kilometres between wintering and nesting areas, stopping at coastal locations such as Panama Bay, Grays Harbour, Wash., our local Fraser River estuary and the Copper River delta in Alaska. Protection of each link in the chain is essential and this is where citizen action can help, by impressing on politicians the importance of protecting birds and nature. The adage “Think global, act local” is still as true as ever, in protecting migrant birds.
B.C. is known for the sea birds that nest on islands and rocky shores along its wild and rugged coast. In contrast to the Arctic and Atlantic coasts where seabird populations have generally increased, thanks to long-term recovery from historical over-hunting, the Pacific coast has seen local declines for species such as Cassin’s auklet and ancient murrelet. The introduction of predators such as rats and raccoons was fatal for some colonies off Haida Gwaii and Vancouver Island.
While this problem is being proactively addressed, seabirds feeding on ocean waters continue to be at risk from entrapment in fishing nets, oil leakage and spills. The proposed Enbridge pipeline would bring oil tankers through key seabird habitats and significantly increase the latter risk. Again, it is up to us citizens to drive political will towards nature protection.
The good news that so many birds still thrive and flourish on our planet is tempered by the fact that some of those species were nearly lost by human mismanagement. Bald eagles were once a rare sight in the Lower Mainland; wintering trumpeter swans were virtually extinct. These species rebounded because people cared enough to do something about them. Let’s hope that the same can be said for the little insect-eating birds, our remarkable seabirds and those extraordinary, long-distance migrating shorebirds, the sandpipers and plovers.
Anne Murray is a writer and naturalist, and the author of two books on the Fraser River delta—Tracing Our Past: A Heritage Guide to Boundary Bay and A Nature Guide to Boundary Bay—both available at bookstores and from Nature Guides B.C.