Star article on the Northern Wheatear

25-gram songbird makes miracle migration to Africa each year

Published On Tue Feb 14 2012

The sharp-eyed northern wheatear is a songbird that weighs a mere 25 grams, about the same as two tablespoons of flour. With its spindly legs, its muted white, brown and black colour, who would think such a lightweight capable of heroic endurance?

For the first time, Ontario scientists have proven what they long suspected — the wheatear is the only songbird that breeds in the Canadian Arctic and Alaska and spends the winter in Africa. The migration can take from one to three months.

They also showed that the wheatear completes the longest known flight over water of any songbird — 3,500 kilometres across the Atlantic. That remarkable passage takes about four days of non-stop flying.

There are two separate populations of wheatears in the far north. One breeds in Alaska, flies west over Russia, Kazakhstan and the Arabian Desert some 14,500 km, ending up in Sudan and Uganda in East Africa. Another, which breeds in the Canadian Arctic near Iqaluit heads the opposite direction, east over the Atlantic, stopping for the winter in Mauritania in West Africa, a journey of 7,500 km.

The study, published Wednesday in the journal Biology Letters, is the research of University of Guelph biology professor Ryan Norris; David Hussell, emeritus scientist from the Ontario Ministry of Natural Resources, and German scientists from the Institute of Avian Research.

“It’s impressive that a bird that size could do this,” says Hussell, speaking from Germany. “I don’t think a lot of North Americans are aware they have this bird migrating to Africa.”

The wheatear has one of the largest breeding ranges in the world, stretching across northern Europe, Asia and North America. With its white rump, the name is said to be a corruption of the Old English descriptor “white arse.”

Hussell, Norris and the German research team tagged 46 wheatears in Eagle Summit, Alaska, and near Iqaluit in 2009 and 2010. They trudged along the rocky tundra looking for birds carrying food back to their nests, which are usually hidden under boulders.

Once they found the birds, new technology allowed them to track their migratory path. Researchers attached tiny backpacks under the wheatears’ wings. The packs were fitted with geo-locators weighing 1.2 grams to record light levels — based on sunrise and sunset. The light levels allow scientists to measure latitude and longitude.

Wheatears have to bulk up for the long days of flight and stuff themselves with insects and spiders. By the time they leave the north, they may have doubled their weight. “If they weighed 25 grams when they took off, they wouldn’t make it,” says Hussell.

They travelled an average of 290 km a day. Those flying overland from Alaska could rest or feed along the way, but the Iqaluit birds flying over the ocean could not.

How migrating birds can fly for days without getting dehydrated has long puzzled scientists. But last year, researchers at Western University (formerly the University of Western Ontario) reported their discovery that birds burn their own muscle and organs as a source of water. Burning protein provides about five times as much water as burning fat.

The following year, the challenge for the scientists tracking the wheatear was to find the same birds once they returned to the summer breeding grounds in the north. They only found one in Iqaluit and three in Alaska.

But it was enough to provide evidence linking the African ecosystems with the Arctic ones.

“It makes it hard when we don’t get many back,” says Norris. “But it’s good evidence that these birds are likely not wintering in North America and make this incredible journey to Africa.”

Robins and Horned Larks!

When I dropped Dave off at work one day this week, there were more than twenty Robins in the fruit trees out front, They were there when I picked him up at the end of the day as well. This was the most numerous group I've seen in quite awhile.

And this morning there was approximately eighteen Horned Larks at Oakville Executive Golf Courses. Again, a large group that we haven't seen since last year.

Also of note, we had a Grackle at the feeders this past week. Unusual for this time of year, but with the mild winter we're having, I think this kind of sighting must not be uncommon.

A reminder that next week is the Great Backyard Bird Count. If you don't have backyard birds, you can visit another spot regularly over the course of the four days and submit your sightings. Give Mother Nature and Science a helping hand!

Of note from the latest BSC newsletter:
New Report on Raptor Population Trends

2 February 2012 – The Raptor Population Index (RPI) has released a new report showing that the majority of North America’s 26 species of migratory raptors (a group that includes hawks, falcons, kites, ospreys, harriers, eagles, and vultures) are either recovering or in stable condition. Unfortunately, the American Kestrel is a stark exception. Long-term declines of this tiny, colourful falcon continue to alarm conservationists, who are calling for increased efforts to monitor populations and identify causes of the decline.
RPI is a cooperative partnership among four leading raptor and conservation organizations: Bird Studies Canada, Hawk Migration Association of North America, HawkWatch International, and Hawk Mountain Sanctuary. Select this link to read a press release about RPI’s new continent-wide assessment of population trends. Full results, including conservation status reports and an online resource featuring easy-to-read maps of population trends for each species, are available on the RPI website.

Dave and I see a Kestrel perched on the wires along Hwy 25, near the 407 almost every morning on our drive to his work. Otherwise, they are not one we see often at all. Hopefully there will be a recovery effort. I'll take "Things for which people are to blame, for 100, please Alex."