July 7, 2006
Turkey Vulture
Turkey Vulture
In April Clay Thompson, in his column on the back page of this section, speculated on the occurrence of turkey vultures in Phoenix.  Yes Clay, we have turkey vultures, particularly March through October.  You'll see them soaring over the desert, large black birds, rocking in flight with wings held in a dihedral (upswept into a "V").

Until recently turkey vultures, just called "TVs" by most birders, were considered birds of prey--raptors like the hawks and owls--because of three physical characteristics:  a wide field of binocular vision; long claws for securing prey; and hooked beaks for tearing open that prey.  In other words, meat eaters.  TVs though, search for carrion, meat that is already dead, and DNA studies and some behavioral traits indicate they are more closely related to the stork family than to the hawks.

TVs have been exquisitely designed by evolution for their role as nature's undertakers.  Though their feet are weak and poorly evolved for seizing and carrying prey, they have long, broad wings for sustained soaring over vast areas in their search for dead animals, and their featherless faces facilitate feeding inside carcasses without requiring extensive clean-up.  This is filthy and disgusting work but somebody has to do it!

When our sons were small and began to recognize vultures and what they did for a living, they would always warn us to "wiggle our toes" whenever we saw soaring vultures so the huge birds would know we weren't dead.  Unlike most other birds, however, TVs have a well developed sense of smell and locate much of their food by its odor rather than by sight.  There have been experiments in remote areas of the west using TVs to locate pipeline leaks.

The best places near Phoenix to see TVs are along the Verde River on the Tonto National Forest, around Sunflower on the Beeline Highway, and at Boyce-Thompson Arboretum State Park.  TVs are migratory and Boyce-Thompson hosts two morning-long vulture workshops, "Bye Bye Buzzards" in the fall (scheduled for Saturday, September 16 this year) and "Welcome Back Buzzards" in the spring.

When not soaring, TVs are typically seen perched early in the morning at overnight roosts, wings outspread to the sun, warming their bodies and drying nighttime dew from their flight feathers as they await the first warm thermal to take them aloft for their daily scavenging.  Like storks, vultures vent their feces onto their legs for evaporative cooling, so the legs of roosting bird often appear white.

Because of their lifestyle the very name, "vulture," has become a pejorative term, and the sight of this species often evokes a shudder of revulsion, but that lifestyle should remind us, like it or not, of the stunning diversity of our birds and the complex tapestry of our universe, where life and death are closely and inexorably interwoven.