Photograph taken by Mike Yip
Turkey Vultures are known for their circular soaring over highways and not so much for their good looks. These birds may not be winning beautiful bird of the world awards anytime soon but they are intelligent and have a highly developed sense of smell (Torres-Mura et al. 2015; Buechley and Sekercioglu 2016; McCabe et al. 2016). Their smell is so well-developed that they can locate a food source hidden in a dense forest or even when it is buried (Buechley and Sekercioglu 2016)!
Video of Phoenix the Turkey Vulture from The Raptor Center, taken by Caitlynn Bright
They will eat muscle, viscera, and bone of dead wild and domestic animals such as birds, reptiles, amphibians, fish, and invertebrates, as well as plant material, garbage, and the occasional live small mammal (Bildstein 2006; Platt and Rainwater 2009; Torres-Mura et al. 2015; McCabe et al. 2016). Turkey Vultures have been known to capture live prey, such as fish, young birds, and sheep when dead prey are hard to find (Torres-Mura et al. 2015). Once a food source is located, Turkey Vultures and other scavengers will fight for dominance to establish a pecking order. Those that come out on top get to eat first.
Photograph by Mike Yip
Photograph from The Cornell Lab of Ornithology: All About Birds
Because the food they eat is littered with bacteria and diseases they have a few adaptations that help prevent them from carrying or catching these diseases. One of these adaptations that helps get rid of bacteria is sun bathing. Turkey Vultures will perch on the ground, in trees, on post, or power line towers with their wings held open in direct sunlight. By doing this they are using the UV radiation of the sun to kill bacteria that could have gotten onto their feathers.
Another one of these adaptations, scientists believe, is that they urinate down their featherless legs instead of ejecting it behind them. Their urine is highly acidic and it is believed that this might ‘sterilize’ their legs by killing pathogenic bacteria and viruses that they could have picked up from carcasses they feed on (Bildstein 2006). This is also why it is prohibited, in both Canada and the United States, to band the legs of vultures since the urine could get caked onto the band and cause infections or other health problems (Bildstein 2006). Instead research groups use satellite tracking, wing banding, and bird watchers to monitor Turkey Vulture populations (Bildstein 2006). The third adaptation is having a bald head. Since Turkey Vulture will get up close to dead bodies, so close they will put their heads into abdominal and chest cavities, it is very helpful having no feathers on their head. This allows them to keep their head clean from contamination.
Juvenile Turkey Vulture Photograph by Mike Yip
Turkey Vultures look almost completely black, except for their under-wing which looks pale brown or silver in colour (Liguori 2005). Young Turkey Vultures have a dark head and bill and as they age their head becomes reddish and their bill becomes white (Liguori 2005). Turkey Vultures can be 68 cm long and weigh 1.4-2.4 Kg ( or 3.08-5.29 pounds) (Bildstein 2006). They use their gigantic wing span of 170 cm to save massive amounts of energy by soaring when they travel and by using warm rising air pockets to gain altitude (Bildstein 2006; Mandel et al. 2008; Buechley and Sekercioglu 2016).
Photograph by Mike Yip
On Vancouver Island they gather in flocks around mid-September, which can be greater than 100 individuals and contain other raptors to migrate south for the winter (Bildstein 2006). Some vultures travel a short distance while others travel long distances during winter migration (Bildstein 2006). Turkey Vultures are the only vulture in the world that travels long distances and over the equator (Bildstein 2006). Turkey Vultures can also fly at an altitude of 4-5 kilometer or roughly 3 miles above the ground (Bildstein 2006). At the end of the year, some Turkey Vultures have traveled a complete round trip journey of roughly 14000 km (Bildstein 2006). In one study, scientists found that one of the Turkey Vultures in the study traveled 327 km in one day and the longest hourly movement was 68 km (Mandel et al. 2008).
Photograph by Mike Yip
Turkey vultures can be found as far north as southern Canada and as far south as the island of Tierra del Fuego in South America (Bildstein 2006). Vultures have a long lifespan and have a slow reproductive rate (Buechley and Sekercioglu 2016). They breed in New Jersey, California, Pennsylvania, and Canada in solitary pairs and then spend the rest of the year in communal roosts which can be up to thousands of individuals (Bildstein 2006; Evans and Sordahl 2009).
Video of a crow solving the string-pulling test
Turkey Vultures are intelligent animals that can problem solve and learn for other members of their group (Ellison et al. 2015). This was discovered after they were tested using string pulling task, which is a test using a piece of meat on the end of a string which is tied to a perch (Ellison et al. 2015). The meat cannot be reach from the ground or from flying straight at it (Ellison et al. 2015). Other scavengers, such as crows and ravens, have also been put to the test and they used their beak to pull up the string and their foot to hold onto the string against the perch (Ellison et al. 2015). Since Turkey Vulture’s feet are not well suited for holding or pulling they used another method instead (Ellison et al. 2015). In contrast, Turkey Vultures used their tongue to pull up the string, swallow it, and store it (Ellison et al. 2015). Once they get the piece of meat, they regurgitated the string (Ellison et al. 2015). When a vulture had a hard time solving this puzzle, they watched another vulture complete the task and then solved it themselves. This shows that they not only learn socially from others but that they can solve problems and become more proficient at tasks over time (Ellison et al. 2015).
Video of Judge Dredd from The Raptor Center performing the string-pulling test
Other vultures have been known to use tools and problem solve in natural environments as well. Like the Egyptian Vulture, who can use a rock to crack open eggs or use a twig to collect wool they will use for their nest from fences (Ellison et al. 2015). Black Vultures will check out plastic bags left behind from people for any food that they could be holding (Ellison et al. 2015).
Turkey Vultures, and vultures in general, may not be much to look at but they are intelligent animals that are vital to our daily lives. Learn more about this in my second post, ‘The Turkey Vulture: A Forgotten Hero‘.
References
Bildstein, Keith L. Migrating Raptors of the World Their Ecology and Conservation. Comstock Publishing Associates a division of Cornell University Press, 2006.
Liguori, Jerry. Hawks from Every Angle: How to Identify Raptors in Flight. Princeton University Press, 2005.
Awesome post! I like that they utilize sun bathing to get rid of parasites, seems like a relaxing way to deal with problems.
On Vancouver Island we don’t get as much sunshine year-round, do you think the Turkey Vultures that live here deal with parasites in other ways to compensate for that?
Thanks! I thought it was very interesting as well. I have not found any alternative methods, in the literature, that they may use for the same function. However, since they migrate south, sometimes all the way to South America, for the winter and return in the spring/summer they may not have to develop another method. Our summers, especially lately, have been very warm and sunny. So, I would assume they do get enough sun while they are here. Also, they have not moved farther north in Canada yet, they are mostly present in southern Canada. According to my research, they also are not present even on northern Vancouver Island and they stay on the southern end of the Island.
Love all the Mike Yip photos! He has tonnes of great books. They make awesome Christmas presents too 😀
I know, they are amazing!!
Nice blog! It seems Annie just cracked open their cognitive abilities with her study. It would be interesting to expand on it to see if they can solve more complex tasks. See if they can give the Caledonian Crow a run for its money. 🙂
That would be amazing! I think there is a lot more to learn about these guys.