Anywhere in Costa Rica it is easy to see several species of Vultures soaring high overhead.
Known in Spanish as «Zopilotes», whether it is the Black Vulture (Coragyps atratus), the Turkey Vulture (Carthartes aura), Lesser Yellow-headed Vulture (Cathartes burrovianus) or the surprisingly majestic King Vulture (Sarcoramphus papa), there is no way you can spend a day in Costa Rica without spotting large flocks of these ghastly yet at times elegant birds. Let’s see some remarks about these impressive and important birds.
Characteristics: Large, heavy-bodied, carrion-eating, black bird, with short tail and broad plank-like wings tipped with white. Wingspan: 5′ Length: 2′-2’4″ W-L ratio: 2.3:1 Weight: 4.5-6 lbs.
Characteristics: Large, dark brown, heavy-bodied and small-headed, carrion-eating bird, with a longish tail and two-toned underwings. Wings held above the horizontal in a strong “V.” Wingspan: 5’6″ Length: 2’2″-2’8″ W-L ratio: 2.4:1 Weight: 3.5-5 lbs
Along with the Turkey Vulture, the Black Vulture is one of the most abundant New World vultures. Prevalent in North America, vultures also breed throughout Central America and much of South America. Black Vultures are typically found in open or partly forested habitats, often in close proximity to human activity. Traditional communal roost sites can consist of 100’s of birds, some of these sites are used for decades at a time, often occupied year-round, especially in areas of temperate climates such as Costa Rica. Roosts are thought to play an important role in the social lives of vultures as a place for juveniles and adults to interact and as a staging area for foraging groups to assemble. Turkey Vultures and Crested Caracaras often roost together with Black Vultures.
Black Vultures have featherless dark gray to black heads and necks and are ugly as hell. They appear completely black when perched, however obvious white patches near the wingtips are clearly visible when in flight and you will see these hideous birds everywhere. The gray legs and toes often are stained whitish with excrement, oh my…..isn’t that nice. Adult Black Vultures have dark bills with bone-colored tips and their heads and the upper half of their necks are dark gray and covered with wrinkles. Unlike Turkey Vultures, an easy distinction between the two species is Black Vultures hold their wings flat when soaring, rock less, and flap more frequently. The Turkey Vulture are masters at soaring above the canopy, rarely flapping their wings and holding them in a “V” shape, while rocking side-to-side, skillfully using the shifting wind thermals to do the work for them.
Unlike the Black Vultures, Turkey Vultures prefer open and forested habitats, typically avoiding urban and suburban areas. In the Americas, both species breed in farmlands, rangelands, forests, and low-elevation mountains. Generally, it only eats the skin and harder parts of the tissue of its meal. Vultures are monogamous and pairs are believed to mate for life. In fact, family members associate more closely with each other than with other individuals over their lifetime. Vultures do not build a nest, instead laying their eggs in rocky crevices, caves, tree cavities, hollow logs, and such. Vultures, though gawky on the ground, perform incredible aerial displays during courtship, with males circling the females with their necks extended, exhaling loudly and making chasing and diving maneuvers. A successful courtship eventually results in two eggs, which are then incubated for 32-45 days. This romantic couple works together incubating the young, with both parents also sharing the feeding of regurgitated food to their young as often as 20 times a day. The little family generally remains in close contact until the next breeding season, at which time the parents chase their offspring away from the nest site. After leaving their parents, juveniles enter a wandering stage while learning how to search for carcasses on their own.
Black Vultures are dirty little opportunistic aerial scavengers. Feeding on carrion of all types and sizes, unlike the Turkey Vultures, this species does not have a keen sense of smell and relies entirely on visuals to locate food. Black Vultures typically fly at higher altitudes than Turkey Vultures and monitor the behavior of predators and other scavengers in order to find their food. They frequently follow successful Turkey Vultures to carcasses, then aggressively chase them away and take it as their own. Large numbers of Black Vultures quickly gather at food sources preferring fresh carcasses, but consuming decaying meat as well.
Occasionally Black Vultures capture live prey, most of which are young, weak, or small sickly mammals or birds. Black Vultures also scavenge through trash, feed on vegetable matter including sweet potatoes, pumpkins, coconuts, and in Costa Rica, the fruit of oil palms. Because Turkey Vultures find food using their sense of smell as well as by sight, they are able to locate carcasses on the forest floor beneath dense forest canopies and are better able to rely on fresh food, but will resort to decaying meat when necessary. Generally, the King Vulture actually prefers to eat the skin and harder parts of the tissue for its meal.
The King Vulture (Sarcoramphus papa) is a colorful large bird found in Central and South America. This vulture lives predominantly in tropical lowland forests stretching from southern Mexico to northern Argentina, and does not frequent the coastal zones as much as the other vulture species. Large with a predominantly white body, the King Vulture has gray to black ruff, flight, and tail feathers. The head and neck are bald, with the skin color varying, including vivid colors of yellow, orange, blue, purple and red. The King Vulture has a very noticeable yellow fleshy caruncle on its beak. This vulture is a hearty scavenger with an exceptionally strong beak and it often is the one to make the initial cut into a fresh carcass. King Vultures have been known to live for up to 30 years in captivity.
The King Vulture can soar effortlessly for hours, only flapping its wings on occasion. While in flight, they hold their wings flat only slightly raising the tips, holding their small heads low, they often appear headless while in flight. These vultures have also been observed engaging in tandem flight which is thought to be a part of their courtship behavior. Only one or two birds generally descend to feed at a carcass, although up to ten or so may gather if there is a significant amount of food. One of the truly most disgusting features of this species of vulture, is it’s said to use urohydrosis, (defecating on its legs) to lower its body temperature. How pleasant, glad to know that. The King Vulture actually lacks a voice box, (wish my husband did sometimes), although it can make low croaking noises and wheezing sounds while in courtship and bill-snapping noises when threatened. The only natural predators for the King Vulture are snakes, which will prey upon the vulture’s eggs and young or large cats such as jaguars, which may surprise and kill an adult vulture while feeding on a carcass.
The reproductive behavior of the King Vulture in the wild is poorly known. From mostly captivity they have learned that King Vultures mate for life and generally lay a single unmarked white egg in a nest in the hollow of a tree. To ward against potential predators, the vultures keep their nests foul-smelling. The parents share incubating and brooding duties until the chick is about a week old, with the chicks later taking their first flights at about three months of age. Because of its large size and beauty, the King Vulture is an attraction at zoos around the world and is a popular photo opportunity when spotted around Costa Rica.
There is no arguing that these beasts serve their purpose in the food chain and natural ecology by providing a natural cleaning up of disgusting roadkill.