Migrants return: Sandhill Cranes, Robins and more

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Our Environment by Katharine Fletcher

Spring birdsong is filling the air, creating a wondrous spring symphony. I’m receiving reports from readers spying Eastern Meadowlarks, Sandhill Cranes, and other species as we welcome our first summer residents back to the Outaouais.

Our Environment by Katharine Fletcher

Spring birdsong is filling the air, creating a wondrous spring symphony. I’m receiving reports from readers spying Eastern Meadowlarks, Sandhill Cranes, and other species as we welcome our first summer residents back to the Outaouais.
North American avian migrants use four major flyways (sky highways) to return to their summer Canadian breeding grounds. The Nature Conservancy of Canada (NCC) identifies these as the Pacific, Central, Mississippi and Atlantic. (NCC’s map: bit.ly/2q68xEv)
This map reveals how some species such as the Great Blue Heron use all four because these herons breed in all provinces except Newfoundland and Labrador. However, species returning to the Outaouais generally use either the Mississippi
or Atlantic (sometimes Central) routes. Banding of Ruby-throated Hummingbirds has shown they return to the same winter and summer grounds; juveniles are somehow imprinted with the route because they don’t travel with their parents.
Prodigious journeys
Flights can be thousands of kilometres extending from Mexico, South or Central America, and the Caribbean to (and from) North America.
Because of their size, Ruby-throated Hummingbirds are perhaps the most astonishing athletes. When these tiny, seemingly fragile birds return from South America, they fly non-stop across the Gulf of Mexico (some 805 km). Recent research proves they can fly 1,930 km non-stop (ti.me/1P0sMpS).
Great Blue Herons are a common wetland species here, and the Canadian Wildlife Federation’s Hinterland Who’s Who notes they migrate to Canada from Mexico, Honduras and Cuba. (bit.ly/2GBD8Rs)
Bobolinks, an increasingly uncommon grassland species, fly 20,000 km “between their wintering grounds in southern South America and their breeding grounds in southern Canada and northern U.S. each year. To navigate this long-distance journey, bobolinks rely on their built-in compass — bristles in the tissues of their nasal cavity that contain iron oxide — to orient them to the Earth’s magnetic fields.” (bit.ly/2H99ILv).
Anthropomorphizing animals
Many people anthropomorphize animals, meaning they attribute human characteristics to them. This habit is interesting when considering migration.
In North American and European cultures, anthropomorphizing is a longstanding tradition. Consider Anna Sewell’s classic 1877 book, Black Beauty (the first book advocating animal rights) or animated films such as Disney’s The Lion King. We have been raised in a culture where animals talk and express human emotions, which educates us to understand animals have feelings, communicate, and have a right to a safe habitat.
However, we attribute characteristics that may not reflect reality. Consider, for instance, seeing migrant birds which arrive in a flock, where one bird remains separate.
I asked Ottawa bird expert Tony Beck to interpret what really might be happening. He replied: “It is fairly common for a variety of species to have a sentinel watching out for predators. When a threat is perceived, an alarm call follows. Often, this brings the group together. At least all the non-predatory animals in proximity to the alarm call will stop their activities and pay attention. Alarm calls typically solicit ‘mobbing’ of the threat. Often a gregarious animal travels solo when it has been injured or compromised in some way. For example, it is rare to see a lone Canada Goose during migration. My first thought when I see one is that it has been injured. Also at this time of year, a bird will move away from a flock if it’s on territory (has found and is protecting its nesting territory).”
Assisting migrants
Bird migrants fly a long way and are exhausted upon arrival. In my next column, I will offer tips on how we can help them.

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