Mark and his daughter picking Elderberries Copyright 2013 Mark Larese-Casanova
Hi, this is Mark Larese-Casanova from the Utah Master Naturalist Program at Utah State University Extension.
Utah’s mountains are abundant with berry-producing shrubs that provide a veritable bounty of food for wildlife. As summer winds down and fall cedes to winter, many birds and mammals try to feed as much as possible to store energy for migration, hibernation, or even just surviving the cold.
One of the most abundant berry-producing shrubs in Utah’s moist mountain canyons is elderberry, Continue reading “Elderberries”
Hi, I’m Holly Strand from the Quinney College of Natural Resources at Utah State University.
It’s almost Halloween so I’d like to tell you about an unusual creature that has given many people a fright. It has a shiny oversized body with long spiny appendages. Dark eyes stare disturbingly from a smooth, bald head. It eats both living and dead matter. And sometimes it engages in cannibalism.
Turkey Vulture in flight Cathartes aura Courtesy Utah Division of Wildlife Resources Scott Root, Photographer Licensed under CCL
Turkey Vulture Kettle above Logan Cathartes aura Courtesy and Copyright Andrea Liberatore, Photographer
Turkey Vulture Kettle above Logan Cathartes aura Courtesy and Copyright Andrea Liberatore, Photographer
On certain days in the spring and fall, the sky above my neighborhood looks like a scene from Alfred Hitchcock’s ‘The Birds’. As many as 60 large black birds swarm the sky, circling above the rooftops. On the busiest of days, people will stop their cars in the middle of the road to gawk at the sight. Some give a visible shiver when told that the birds are turkey vultures. But we have nothing to fear from these birds – in fact they should be embraced for the absolutely vital role they play in our environment.
There are lots of myths surrounding vultures, which in turn creates a misunderstanding about them. So let’s set the record straight on a few things. Vultures circle for two main reasons, neither of which involves waiting for a sick or wounded animal to die. The first reason is to take advantage of rising columns of air, called thermals, which generally occur in the mornings as the sun warms the air closest to the earth. Vultures are soaring birds and flapping their 6-foot wingspans takes a lot of effort, so they rarely do it. In fact these birds can fly for hours without a single flap. Circling within a thermal helps them travel higher and farther on much less energy.
The second reason vultures circle is to hone in on a food source. Turkey vultures are one of the few birds that have a highly developed sense of smell. Working together with their excellent eyesight, the birds soar and circle to pin down the location of their next meal.
What links this melodious thrush of northern Utah forests
(Kevin Colver: Song Birds of Yellowstone)
with a hawk that soars over farms, range lands and prairies in western North America?
Both Swainson’s Thrush and Swainson’s Hawk are named after the 17th century self-taught British naturalist, William Swainson. He was a contemporary of John James Audubon. Like Audubon, Swainson was a passionate solo collector, taxidermist and skilled illustrator of birds. Unlike Audubon, Swainson’s single intensive field expedition took him far to the south, sailing to eastern Brazil. During his two year stay, he amassed a collection of 20,000 animal specimens, including 760 bird skins. Swainson ultimately named 20 species new to science. Although he never visited North America, he nonetheless co-authored an encyclopedic four volume treatise about North America’s fauna.
Swainson’s Hawk and Swainson’s Thrush share another similarity, this one biological. Both birds migrate long distances to escape winter’s cold and hunger. Swainson’s Thrush winters in balmy tropical forests of South America. Swainson’s Hawk soars farther, all the way to the arid Argentine pampas. There this large slender hawk dines mostly on big flying insects, particularly grasshoppers and even dragonflies. Swainson’s Hawks migrate in groups, often along regular corridors. Every September, Hawkwatch volunteers and hardy birders have reported hundreds of Swainson’s Hawks rocketing past the Wellsville Mountains of northern Utah, flying amid several thousand migrating raptors of all kinds.
Birds migrate to avoid the snow, cold and lean times of northern winters. Migration poses natural risks, of course. Hawkwatch ornithologists also suspect that widespread use of two deadly organophosphate insecticides on Argentine crops kills many insect-eating Swainson’s Hawks. The plow, pavement and subdivisions have also reduced this hawk’s historic northern range, especially in California. In addition, foolish people still shoot this relatively tame hawk, not caring that its diet of rodents and grasshoppers benefits our farmers and ranchers.
Professional disappointments drove the quarrelsome William Swainson south as well, to New Zealand, where he died in anonymity. His namesakes, Swainson’s Hawk and Swainson’s Thrush, live on to cross and recross the equator in pursuit of perpetual summer and the feast it provides.
This is Linda Kervin for Bridgerland Audubon Society.
