The Wandering Ibis

American_White_IbisEWhen a Good Samaritan delivered a juvenile American White Ibis to the Outer Banks Wildlife Shelter in Newport a few weeks ago, she was an odd and pathetic sight for sure. She was missing all feathering from her abraded head and face, and her right eye was swollen and bulging, although her limbs were intact with no injuries found. Not a pretty sight, but what did make her attractive to our staff was her cooperative and pleasant demeanor. Her young age probably attributed to that. We aren’t sure what happened to rough her up in the way she sported, but we and possibly, she, knew medical attention was warranted. She tolerates the application of medicine to her injuries and enjoys spending time in the deep sink catching small fish. She eats very well, which is a good sign. Ibis5XEAug2013The long-legged wader is coming along, but time will tell if she’ll make a full recovery. This little wader is associated with a group comprised of egrets, herons, spoonbills, storks and flamingos. Although a diverse bird group, they are united by their slender, long legs that enable them to wade for food. Found in a variety of habitats, they prefer shallow coastal marshes, wetlands and swamps, but also frequent muddy pools, flooded fields and even wet lawns. Ibises and spoonbills are the most closely related of the wader group, but there is a striking difference in bill shape. Both are odd looking birds because their bill is enormous compared to the tiny head it’s attached too. The Ibis bill is down-curved and pointy on the end while spoonbills have straight bills that broaden at the end. Ibises use their bills to probe in mud to catch prey, while spoonbills move their bill side to side in the water to find food. The tactile, non-visual nature of the Ibis’ probing for food means it catches prey that are too slow to evade the Ibis once located by its bill. The Ibis diet consists primarily of small aquatic prey such as insects and small fish, but will also dine on frogs, snails, marine worms and snakes. Crayfish are its preferred food in many regions; however, adjustments are made according to habitat and prey abundance. American White Ibises that feed in swamps focus on crabs, but fish are a more energy-rich food source. At night Ibises roost with other marsh wader species in trees that are near and often overhanging water. In breeding season, American White Ibises travel further to forage in freshwater wetlands rather than nearby saltwater areas where fiddler crabs are often the food choice. This species is known to wander, and has been sighted, sometimes in small flocks, in states far out of its usual range, which is south of Virginia and west to Texas. The Ibis is a medium-sized bird with an overall white plumage, bright red-orange bill, long legs and toes and black wing tips that are rarely visible unless in flight. However, juveniles are variations of brown, including the bill, with white feathered underparts. In non-breeding season the down-curved bill and long legs are bright red-orange as an adult, but during breeding season the bill turns a deep pink and their legs purple-red. Males are significantly larger and have longer bills than females. Their wingspan measures 35 to 41 inches. They can soar to 3,300 feet; however, more commonly they stay within the 200 to 350 feet range. During the breeding season, which begins in its third year, the American White Ibis gathers in huge colonies known to number 30,000, near water. _LT_3599CSEPairs are predominantly monogamous and both parents care for the young, although some males have been known to wander, engaging in ‘affairs’ with other females to increase their reproductive success. Males also have a bad habit of stealing food from unmated females and juveniles during the breeding season. Nesting begins as soon as suitable foraging and nesting habitat is available. The female selects the site, usually in the branches of a tree or shrub, close to and often over water, and builds the nest, and males assist by bringing nest material. One to five eggs are typically laid, with two or three being the most common. The eggs are matt, pale blue-green in color with brown splotches. A field study reveals on an average day, adult American White Ibises spend 10 hours looking for food, 45 minutes flying and 13 hours resting, roosting and attending to nests or young. Much of the time roosting is spent preening, biting and working their feathers with their long bills, as well as rubbing the oil from glands on the sides of their head onto their back. The American White Ibis is known to be territorial, defending the nest against intruders such as the Fish Crow, Boat-tailed Grackle, Gull, Black-crowned Night Heron, Opossum, Vultures, Rat Snake or Raccoon which make the list of the most common predators of Ibis eggs or young and account for about a 44% loss every breeding season. That lengthy list of predators and loss tell us it’s not easy being an Ibis! Nest attentiveness by the parents, high nest densities and that long bill used to pinch, squeeze and hold a potential predator’s head are their best defensive tactics. Kind of think that last one would only work with bird predators or maybe the snake! High Tides have also been the cause of egg disappearance or nest disruption. The longevity of the Ibis has been recorded as approximately 20 years in captivity and although life is definitely risky for the Ibis in the wild, a wild bird has been picked up 16 years and 4 months after being banded. Think they named that one Lucky!

Have a great Autumn Everyone!!!
Linda Bergman-Althouse
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