COLUMN: Turkey vulture migration under way

     Have you noticed the unusually large flocks of large birds drifting and spiraling across the sky the past few weeks? Most likely what you are seeing are migrating turkey vultures. Don’t worry; they are not indicating the presence of a large meal nearby. Turkey vultures have been heading south in large numbers the past few weeks as they try to stay ahead of the very cold weather that, as changing seasons dictate, will soon arrive. People lucky enough to look overhead as these birds fly by will be astonished at their aerial abilities.

     Turkey vultures are very graceful while in flight and can soar for hours at high altitudes without flapping their wings. They are one of the only large birds that fly with their wings in a shallow dihedral (v-shape). This dihedral helps them maintain their stability and gives them a teetering appearance while flying. Nearly eagle-sized with a 6-foot wingspan, these blackish eagle-like birds have two-toned wings, darker at the shoulders and lighter at the wingtips. Their naked heads also look relatively small for their size while in flight.

     Turkey vultures often forage alone but will gather at roost sites, feeding locations, in thermals near river bluffs, and while migrating. They are widespread and found across the United States, north into Canada and south into Central America. It is believed that the warmer climate and increased availability of road kills has led to much of the northward expansion of the turkey vultures range. Yet turkey vultures do not like cold temperatures and migrate south for the winter. Their fall migration and disappearance from Iowa is often a good indicator that winter is truly coming.

     Groups of turkey vultures are called “kettles.” Turkey vultures have been reported by aircraft pilots as high as 20,000 feet and have been found to travel as far as 200 miles in one day while migrating.

     Most people know turkey vultures prefer to dine on carrion. They spend hours soaring above the ground using their excellent eyesight and highly developed sense of smell to locate a tasty meal below. You can often see turkey vultures along area roadsides cleaning up fresh road kill or along area rivers, eating dead fish that have washed up to shore. It has been found that vultures prefer carrion less than 12-24 hours old and don’t seek out extremely rotted carcasses.

     Turkey vultures are perfectly adapted for their gruesome cleanup job. Scarce feathers on their head help keep the mess to a minimum, thus giving these pink bare-skinned faced birds a very distinctive look when up close. Male and female turkey vultures appear identical. Immature turkey vultures will have a darker head. It is said that they were named turkey vultures because of the resemblance of their featherless red head to that of a wild turkey.

     If you’ve never seen a turkey vulture nest, it’s because they don’t build their own nest. Turkey vultures choose caves, rock piles, hollow tree stumps, cliff ledges, or old barns as nesting sites where they can lay from one to three blotchy looking eggs. Both parents incubate and care for the young. Incubation during the summer can take from 38 to 41 days. Young are then fed regurgitated food and will leave the nest in 10 to 11 weeks.

     Their method of feeding young is not their only nasty adaptation for survival. During the summer months turkey vultures will defecate on their own legs, using the evaporation of the water in the feces to cool themselves down. Another not-so-becoming vulture tidbit is their defensive tactic of vomiting on anything that startles or threatens it. Wow, make sure you don’t get too close to these guys or you had better be prepared for the consequences.

     As temperatures cool in the fall, vultures will use the sun in order to get warm enough to fly. You may observe them as they sit in a tree or on a cell phone tower with their wings spookily outspread catching some sun.

     Most people never hear the call of a turkey vulture because they make very few vocalizations, usually consisting of hisses and grunts. Hissing is usually used when they feel threatened.

     Turkey vultures are protected by the International Migratory Bird treaties and are increasing in population. Turkey vultures that survive their first year can live to be over 24 years old.

     Locally a few great places to watch migrating turkey vultures are along the Maquoketa and Wapsipinicon River valleys, Whitewater Canyon, and the SE corner of Central Park. Watch in the evening for migrating kettles to gather and land as they roost for the night. If you would like more information on turkey vultures, visit https://www.allaboutbirds.org/guide/Turkey_Vulture/id.