I glanced out the kitchen window on a cool, cloudy morning recently, just as a flock of golden-crowned sparrows swept into my yard. They descended on the lawn and feeders, hopped over the rockery and under the hedge, checking out every inch of the garden.
From their behaviour, they were clearly migrating. Having flown through the night, they were tired, hungry and in need of a quiet location to recharge. Some golden-crowned sparrows winter in the lower mainland and nest in B.C.’s north, but they also range much further afield. These birds could have travelled from Northern California and be headed to nest sites in the Gulf of Alaska.
Mixed up with the 15 or so sparrows, were a few other birds: fox sparrows, white-crowned sparrows, dark-eyed juncos and American robins. It is not uncommon for different species to flock together on migration, sometimes bringing along more unusual birds in their midst. Among tens of thousands of dunlin, western sandpipers and black-bellied plovers feeding on local mudflats, the occasional red knot, sharp-tailed sandpiper or willet may be seen. Rare birds can get birdwatchers and photographers very excited. Earlier this year, a red-flanked bluetail showed up in a New Westminster park. This little bird was far afield of its normal home in Asia.
Since the invention of geolocators, many new discoveries are being made about bird migration. Geolocators are tiny devices carried on a bird’s back, tracking its flight by measuring daylight length. A Pacific golden-plover was recorded flying 96 km/h on a 24,000-km route around the Pacific ocean. Two wheatears were tracked from Alaska, through Russia and Arabia, to East Africa, a round-trip of 30,000 kms. Black swifts, which sweep into southern B.C. during the humid days of early June, were shown to be incredibly fast fliers, covering 340 kms in a single day.
There are many opportunities to see migrating birds in the Lower Mainland. Many travel at night and make landfall early in the morning, which is a good time to be out observing them. Check for shorebirds and gulls on the beaches at White Rock. The mouth of the Nicomekl River at Blackie Spit, Crescent Beach, is very valuable habitat for shorebirds such as least sandpiper and greater yellowlegs. Whimbrel, a larger shorebird with a curved bill, was recently seen here. Blackie Spit is one of the few places in the Lower Mainland where there are breeding purple martins, members of the swallow family. Forest parks and woodlands along streams are good places to listen for warblers, thrushes and vireos. Bright-coloured black-headed grosbeaks and western tanagers are often hidden in the thick canopy of broadleaf trees, but can be located by their loud, robin-like songs. If you are walking a dog, please keep it well under control when birds are migrating, as they need to feed and regain energy without too much disturbance.