Spring migration has begun

By Bob Wood

Spring migration has begun.

Are you seeing more or fewer birds flying overhead or foraging in your backyard?

There is no simple explanation as one learns from Birds Canada’s annual State of Birds.

This comprehensive report produced by Port Rowan-based Birds Canada and the federal government’s Environment and Climate Change Canada was released in November and is available online.

The report analyzes data from many sources going back to the 1970s that shows the percent change in populations over time.

Some species are doing well, others not so much.

Of 463 species counted, 143 (31 per cent) have increased in numbers and 163 (36 per cent) have declined. For another 54 species, there is not enough data to determine trends.

Generally speaking, wetland birds (such as swans, geese and most ducks), birds of prey and waterfowl have seen their numbers increase.

The wood duck, for example, is arguably the most attractive of ducks. The male has a green head and chestnut breast. Its’ unique because it nests in tree cavities. Wood duck populations have increased dramatically since the ’70s due to increased habitat, conservation efforts, the building of nesting boxes, and more effective hunting regulations. You can find wood ducks in the ponds on Front Road at Birds Canada and the Port Rowan wetlands. Another bird often found at the Port Rowan wetlands in years past isn’t doing as well.

The least bittern is the tiniest heron in the world but is not well known because of its size and secretive habits. Its numbers are stable. The least bittern is a threatened species due to the loss and degradation of wetlands.

Forest birds are not doing well. The evening grosbeak is typical. There are about 2 million of these birds in Canada—over half of the global population. The evening grosbeak gathers in large flocks to feast on seeds and berries through much of the year. In the summer, its diet is mainly insects like the spruce budworm. This bird’s numbers have declined drastically but the reasons for the decline are not clear.

“If we understand, if we act, we can do something,” Birds Canada’s Pete Davidson, who is vice-president of science and monitoring at Birds Canada, told those attending the meeting.

Farmers may be surprised but barn swallows (an aerial insectivore) are in decline.

They nest on human built structures and there are an estimated 6.4 million in Canada. The Canadian population was assessed as threatened in 2011. The species has rebounded somewhat but is still in need of conservation attention.

Aerial insectivores, Arctic birds, long-distance migrants, shorebirds, and grassland birds are all in trouble. In fact, many grassland birds have declined so severely that several are at risk of disappearing from Canada.

Researchers say the rise and fall of bird populations tells us how they, and by extension their habitats, are doing. Birds reflect our impact on the environment, tell us where conservation action is working, and show us where we need to focus more effort. “We must work together to halt and reverse these trends, and ensure these groups recover,” says Davidson.

You can help bridge the data gap by becoming a Citizen Scientist today. Find out how at Citizen Science – Birds Canada or by calling Birds Canada at 519-586-3531.

Originally printed in The Good News, April 2025.