Jul
24

Of California Condors and Turkey Vultures

You no doubt heard this last week that the decades-long effort to revive the nearly extinct California condor has hit a milestone – the 1,000th condor chick hatched recently in Zion National Park, in southern Utah.

In 1982, 22 California condors existed in the wild. Captured and held in captivity for safe keeping, and a breeding program to reintroduce them, the first youngsters were released back to the wild in 1992 in California and 1996 in Arizona. There are now more than 500 condors. About half of them flying over parts of Arizona, Utah, California and northern Mexico.

This is a big deal. Female condors lay one egg per nesting attempt, and they don’t nest every year. Reaching adulthood is a challenge for condor chicks. Adult condors may restrain an overenthusiastic nestling by clamping it down with a foot on its neck (this is also a common way for an adult to get a youngster’s bill from its throat at the end of a feeding). Young depend on parents for a year or more, and reach maturity in eight years. They often take months to perfect flight and landings, with crash landings observed several months after a first flight. Of today’s 500 living birds, the oldest has reached 40 years, although they may live to 60 or more.

Worldwide, there are some 23 species of vultures. The New World vultures – scientific family Cathartidae – includes seven species of vultures and condors in the Americas. Three species are North American: California condor (Gymnogyps californianus Shaw), turkey vulture (Cathartes aura Linnaeus) and black vulture (Coragyps atratus Beckstein). Vultures are generally called birds of prey because of diet, but in fact they are most related to storks and herons.

Black vultures are only found in the southeastern U.S. states and Mexico. Today, California condors are found in the canyons and mountains of the states and regions mentioned above, although in Lewis and Clark days, 1805, they were observed in the Northwest. Turkey vultures are our common scavenging friends here in Paradise. Indeed, they are now expanding their range into Canada and across the U.S.

I’m often asked about sizes of these vultures. Clearly, the condor is the largest, weighing from 16 to 22 pounds, some four feet from nose to tail and about nine feet from wingtip to wingtip. The condor is the largest North American bird (there are larger condors on the planet). Our turkey vultures, a distant second, may weigh over five pounds, reach nearly three feet in length, and boast six foot wingspans. The black vulture of the Southeast will weigh up to four pounds, reach 2.5 feet in length and have wings that cover nearly five feet.

Vultures and condors are communal feeders, gathering on carcasses to feed. A soaring condor or turkey vulture may spot a carcass the size of a jackrabbit from four miles away, and see gatherings of its fellows from eight miles. (The turkey vulture is one of very few birds able to find food by scent.) At carcasses, the condor will dominate the feeding – observed yielding only to the sharp and powerful talons of the golden eagle. Featherless heads allow them to probe and dig through a carcass without becoming caked with gore, and their digestive systems have been shown to kill most any ingested virus or bacteria. These birds – Nature’s waste disposal technicians – perform a valuable service for which they are perfectly suited.

Low wing loading (bird weight to wing area ratio) and low aspect ratio (length to width of wings) enable them to soar easily, slowly, and steadily on relatively light thermal updrafts. Turbulence found with such wing characteristics is largely alleviated with the spreading of the stiff, tapered primary feathers at the wing tips. For all vultures, relatively weak pectoral muscles can limit takeoffs; after a big meal, a condor or vulture may puke up (regurgitate for you sophisticates) part of a big meal to be light enough to take off. These birds can go without eating for a couple weeks, and can actually store meat in a sort of crop when excess is available – and takeoff is manageable.

Both birds thermoregulate on hot days by dumping their own body waste over their legs. The evaporating liquid cools the blood flowing through the legs, thus cooling their body cores. They bathe regularly to prevent waste buildup on their legs.

California condors are year-round residents in their habitat. Our turkey vultures arrive in April to breed and rear young. By first snow, they will be cleaning up the dead in the Bahamas or Central or South America.

These are unique, fascinating, and misunderstood creatures – among my favorites to watch. While I studied them years ago in Colorado, I bow to Deborah Essman, the Bird Whisperer of Paradise, who has caught, handled, fed, dissected and been puked upon by vultures, yet retains a wild enthusiasm for them.

The Science Education Subcommittee of the Reecer Creek Rod, Gun, Working Dog & Outdoor Think Tank Benevolent Association suggests “condors” or “vultures” at www.allaboutbirds.org/ for far more info than I include here.

Go look around canyons and cliffs in our valley or urban/rural areas most anywhere in the state. Watch for bare heads and wings in a shallow “V” shape (eagles soar with flat wings). Find a “kettle” of vultures – any number of them soaring on a thermal (aka, committee, wake, venue or volt of vultures). As they ride, they are said to be “kittling.” Go look. It can be almost breathtaking.

Written by Jim Huckabay. Posted in Uncategorized

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