Description and biology
The Oriental white stork is also known as the Japanese white stork and the Far Eastern white stork. With a body length of 43 to 45 inches (110 to 115 centimeters) and a wingspan of about 46 inches (118 centimeters), it is bigger than its cousin, the European white stork.
It has a distinctive black bill and long white wings with black tips. Male Oriental white storks, weighing about 11 pounds (5 kilograms) are larger than females, which weigh about 10 pounds (4.7 kilograms).
The Oriental white stork’s diet is made up of insects, fish, frogs, snails, small reptiles, and small mammals, such as rodents. The stork is a migratory bird, traveling very long distances to relocate seasonally. It tends to be quite aggressive with other members of its species.
Breeding male and female Oriental white storks make their nests in sections of the forest as far away from human communities as possible. The nests are made from branches and straw and are about 6.5 feet (2 meters) in diameter. The female stork usually lays about four or five eggs. Then the male and the female take turns incubating, or sitting on the eggs to keep them warm.
When the chicks are born, both parents feed them by regurgitating (vomiting) undigested food into their mouths. The young leave the nest after about 65 days and begin to find their own food. In captivity an Oriental white stork lives about 48 years.
Habitat and current distribution
The Oriental white stork lives only in the wilderness. It currently breeds in the Amur and Ussuri regions of southeast Siberia in Russia and in northeast China. These storks migrate each winter.
Most travel a distance of about 1,860 miles (3,000 kilometers) to spend the winter in the Yangtze River valley in China. Some storks winter in Hong Kong, Taiwan, Japan, and North and South Korea. The total population of Oriental white storks in the world is estimated to be between 2,000 and 2,500 individual birds.
History and conservation measures
The Oriental white stork once had a large range in Asia. It became extinct as a breeding species in Japan in 1959, and in North and South Korea in 1971. In the past, Oriental white storks spent winters in India, Myanmar, and Bangladesh, but the species is no longer to be seen in those countries.
The reasons for the decline in the Oriental white stork population are human–related. The trees that the storks nest in have been cleared and the wetlands (areas where there is a lot of water in the soil, such as swamps or tidal flats) where they find their food have been drained.
In Japan and the Koreas, people hunted the birds until the population had totally vanished from those countries. Pollution has probably further reduced the populations.
In China, the building of the Three Gorges Dam on the Yangtze River and other hydro–electric (creating electricity from water power) projects are expected to have a heavy impact on the Oriental white stork’s habitat. In Russia, development of the wetlands for farming has crowded the birds into increasingly smaller regions.
Russia, China, South Korea, and Japan have enacted strictly enforced laws protecting the Oriental white stork. After the species became extinct within the country, Japan created special reserves for the stork, notably the Hyogo Prefecture in Toyooka City, established on the site where storks once nested in Japan. There, Oriental white storks have been bred in captivity; about 200 now exist in the reserve.
The reserve has a special section where storks are trained to hunt and fly before being released into the wild. It also has facilities for research into the species. Russia and South Korea have also established reserves for the Oriental white stork.
Conservationists (people who work to protect nature and natural resources) are studying ways to create a better habitat for the storks by planting elm trees near their feeding areas.
One of the great difficulties in conservation with this species is its migratory (relocating) habits: its welfare depends on the abilities of several countries to work in concert with one another to protect it.
Madagascar Teal
Description and biology
The Madagascar teal is a small duck of about 16 inches (40 centimeters) in length, weighing about 1 pound (450 grams). The plumage (covering of feathers) is brownish gray, and there is a black–and–white band on each wing. The feathers under the wing are gray with white edges. The Madagascar teal has a long neck, large eyes, and a light red bill.
The Madagascar teal is found in either fresh or salt water where there is abundant plant life and rich mud. Like all teals, it is a “dabbler” (rather than a diver); it feeds while wading in shallow waters less than 4 inches (10 centimeters) deep by sifting through the water and mud for invertebrate (lacking spinal column) animals and some water plant seeds.
The teal sifts for food throughout the day and night, but prefers the morning and evening hours. It walks well on land and has wings large enough to fly very slowly.
Madagascar teals are monogamous: once a male and female mate, they stay together for life. Breeding takes place from December to March, the rainy season in Madagascar. The male and female build a nest, usually in a hole in a mangrove tree trunk.
They are territorial and will defend their territory against other teals. The female produces about six eggs and incubates them (sits on them to keep them warm) for about a month. The male watches over the female carefully while she is tending the eggs.
The ducklings are well developed when they hatch, covered in soft down and able to move about and eat by themselves. Within about six weeks from hatching they will be able to fly. When not breeding, groups of teals form small flocks. The female Madagascar teal makes a quacking call; the male makes a whistling sound.
Habitat and current distribution
The Madagascar teal lives in very limited areas of the coastal wetlands of western Madagascar, an island nation off the southeast coast of Africa. The total population is estimated to be between 500 and 1,000 birds and is declining.
History and conservation measures
Before humans arrived on Madagascar 2,000 years ago, there is evidence that the Madagascar teal had a much greater range throughout the island. The species was first discovered in 1860 (when it became known as Bernier’s teal), but none were observed for nearly a century and the species was virtually forgotten.
Then, in 1969, the species was “discovered” again. Still, little was known about this teal. In 1992, the Durrell Wildlife Conservation Trust began extensive research on the species, finding that the population had dipped drastically.
A growing population of humans in Madagascar throughout the breeding range of the teal has caused extensive habitat loss. In particular, most of the shallow muddy waters that these ducks require for feeding have been converted into rice fields. The mangrove trees in which the teals build their nests have been cleared for timber and agricultural uses.
The Durrell Wildlife Conservation Trust moved quickly in the 1990s to initiate a breeding–in–captivity program, which has been highly successful. The organization has also been responsible for shedding light on the habits and habitat requirements of this previously little–known species and for educating local people living within the teal’s habitat areas about the plight of the Madagascar teal.
The Madagascar teal is a small duck of about 16 inches (40 centimeters) in length, weighing about 1 pound (450 grams). The plumage (covering of feathers) is brownish gray, and there is a black–and–white band on each wing. The feathers under the wing are gray with white edges. The Madagascar teal has a long neck, large eyes, and a light red bill.
The Madagascar teal is found in either fresh or salt water where there is abundant plant life and rich mud. Like all teals, it is a “dabbler” (rather than a diver); it feeds while wading in shallow waters less than 4 inches (10 centimeters) deep by sifting through the water and mud for invertebrate (lacking spinal column) animals and some water plant seeds.
The teal sifts for food throughout the day and night, but prefers the morning and evening hours. It walks well on land and has wings large enough to fly very slowly.
Madagascar teals are monogamous: once a male and female mate, they stay together for life. Breeding takes place from December to March, the rainy season in Madagascar. The male and female build a nest, usually in a hole in a mangrove tree trunk.
They are territorial and will defend their territory against other teals. The female produces about six eggs and incubates them (sits on them to keep them warm) for about a month. The male watches over the female carefully while she is tending the eggs.
The ducklings are well developed when they hatch, covered in soft down and able to move about and eat by themselves. Within about six weeks from hatching they will be able to fly. When not breeding, groups of teals form small flocks. The female Madagascar teal makes a quacking call; the male makes a whistling sound.
Habitat and current distribution
The Madagascar teal lives in very limited areas of the coastal wetlands of western Madagascar, an island nation off the southeast coast of Africa. The total population is estimated to be between 500 and 1,000 birds and is declining.
History and conservation measures
Before humans arrived on Madagascar 2,000 years ago, there is evidence that the Madagascar teal had a much greater range throughout the island. The species was first discovered in 1860 (when it became known as Bernier’s teal), but none were observed for nearly a century and the species was virtually forgotten.
Then, in 1969, the species was “discovered” again. Still, little was known about this teal. In 1992, the Durrell Wildlife Conservation Trust began extensive research on the species, finding that the population had dipped drastically.
A growing population of humans in Madagascar throughout the breeding range of the teal has caused extensive habitat loss. In particular, most of the shallow muddy waters that these ducks require for feeding have been converted into rice fields. The mangrove trees in which the teals build their nests have been cleared for timber and agricultural uses.
The Durrell Wildlife Conservation Trust moved quickly in the 1990s to initiate a breeding–in–captivity program, which has been highly successful. The organization has also been responsible for shedding light on the habits and habitat requirements of this previously little–known species and for educating local people living within the teal’s habitat areas about the plight of the Madagascar teal.
White-breasted Thrasher (Ramphocinclus brachyurus)
Description and biology
An average white–breasted thrasher measures 9 to 9.5 inches (23 to 24 centimeters) long. The color of the plumage (covering of feathers) on the majority of the bird’s body is dark brown. The side of its head is black, and its underparts are strikingly white.
This thrasher often gathers in single pairs or in small flocks of four or five pairs. It feeds by foraging on the ground for insects, seeds, and berries. The white–breasted thrasher is very territorial: when threatened, it will cock its tail and chatter like a wren. (Thrashers tend to sing in short, musical sounds. Birds like wrens often make scolding, chattering sounds.)
Breeding season appears to take place between April and July. The female white–breasted thrasher lays a clutch (eggs produced at one time) of 2 greenish–blue eggs in a bulky nest made of twigs and leaves.
Based on related species, biologists (people who study living organisms) estimate that it probably takes 12 to 13 days for the eggs to hatch. The nest is often found 7 to 20 feet (2 to 6 meters) above ground in young trees.
The white–breasted thrasher species is divided biologically into two subspecies: Ramphocinclus brachyurus brachyurus and Ramphocinclus brachyurus santaeluciae. The main physical difference between the two is color. The birds of the subspecies brachyurus are lighter than those of the subspecies santaeluciae.
Habitat and current distribution
The white–breasted thrasher is unique to the Caribbean islands of Martinique and Saint Lucia. Martinique is home to the thrasher subspecies brachyurus. Biologists estimate that between 15 and 40 pairs of these birds currently exist. On Saint Lucia, home to the thrasher subspecies santaeluciae, fewer than 50 pairs of birds exist.
White–breasted thrashers prefer to inhabit dense thickets in semi–arid (partly or mostly dry) woodland. Those thrashers on Martinique have also been found to inhabit deep woods and areas bordering streams. On Saint Lucia, some thrashers have been observed inhabiting deciduous (shedding) trees ranging in height from 10 to 70 feet (3 to 21 meters).
History and conservation measures
The white–breasted thrasher is one of the rarest birds of the West Indies. Although considered quite common on Martinique in the nineteenth century, the bird was considered extinct there by 1950. That same year, it was rediscovered on the Presqu’île de la Caravelle, a peninsula that juts 5 miles (8 kilometers) out from the island into the Atlantic Ocean.
On Saint Lucia, the thrasher was also considered common and widespread during the nineteenth century. By the 1930s, however, it was extinct in some areas and rare in others on the island.
Habitat destruction on both Martinique and Saint Lucia has been, and continues to be, one of the major threats to the white–breasted thrasher. The bird is also threatened by introduced predators such as mongooses and rats. The white–breasted thrasher is easy prey for these animals because it spends much time feeding on the ground and it is not a strong flier.
On Martinique, the white–breasted thrasher’s range lies within the Caravell Natural Reserve. On Saint Lucia, part of it lies within the Castries Forest Reserve.
An average white–breasted thrasher measures 9 to 9.5 inches (23 to 24 centimeters) long. The color of the plumage (covering of feathers) on the majority of the bird’s body is dark brown. The side of its head is black, and its underparts are strikingly white.
This thrasher often gathers in single pairs or in small flocks of four or five pairs. It feeds by foraging on the ground for insects, seeds, and berries. The white–breasted thrasher is very territorial: when threatened, it will cock its tail and chatter like a wren. (Thrashers tend to sing in short, musical sounds. Birds like wrens often make scolding, chattering sounds.)
Breeding season appears to take place between April and July. The female white–breasted thrasher lays a clutch (eggs produced at one time) of 2 greenish–blue eggs in a bulky nest made of twigs and leaves.
Based on related species, biologists (people who study living organisms) estimate that it probably takes 12 to 13 days for the eggs to hatch. The nest is often found 7 to 20 feet (2 to 6 meters) above ground in young trees.
The white–breasted thrasher species is divided biologically into two subspecies: Ramphocinclus brachyurus brachyurus and Ramphocinclus brachyurus santaeluciae. The main physical difference between the two is color. The birds of the subspecies brachyurus are lighter than those of the subspecies santaeluciae.
Habitat and current distribution
The white–breasted thrasher is unique to the Caribbean islands of Martinique and Saint Lucia. Martinique is home to the thrasher subspecies brachyurus. Biologists estimate that between 15 and 40 pairs of these birds currently exist. On Saint Lucia, home to the thrasher subspecies santaeluciae, fewer than 50 pairs of birds exist.
White–breasted thrashers prefer to inhabit dense thickets in semi–arid (partly or mostly dry) woodland. Those thrashers on Martinique have also been found to inhabit deep woods and areas bordering streams. On Saint Lucia, some thrashers have been observed inhabiting deciduous (shedding) trees ranging in height from 10 to 70 feet (3 to 21 meters).
History and conservation measures
The white–breasted thrasher is one of the rarest birds of the West Indies. Although considered quite common on Martinique in the nineteenth century, the bird was considered extinct there by 1950. That same year, it was rediscovered on the Presqu’île de la Caravelle, a peninsula that juts 5 miles (8 kilometers) out from the island into the Atlantic Ocean.
On Saint Lucia, the thrasher was also considered common and widespread during the nineteenth century. By the 1930s, however, it was extinct in some areas and rare in others on the island.
Habitat destruction on both Martinique and Saint Lucia has been, and continues to be, one of the major threats to the white–breasted thrasher. The bird is also threatened by introduced predators such as mongooses and rats. The white–breasted thrasher is easy prey for these animals because it spends much time feeding on the ground and it is not a strong flier.
On Martinique, the white–breasted thrasher’s range lies within the Caravell Natural Reserve. On Saint Lucia, part of it lies within the Castries Forest Reserve.
Black-capped Vireo (Vireo atricapillus)
Description and biology
The black–capped vireo (pronounced VEER–ee–o), also called the black–capped greenlet, is a small songbird that averages about 4.7 inches (12 centimeters) in length. The color of the male’s plumage (covering of feathers) is dull yellowish–green above and whitish below.
The female is slightly darker above with yellowish underparts. The head is black in the male and gray in the female. Both have white eye markings. The bird forages in leaves and branches for insects, spiders, fruit, and seeds.
A female black–capped vireo lays a clutch (eggs produced at one time) of 3 to 5 eggs in a rounded nest made of vegetation. Both the male and female take turns incubating (sitting on or brooding) the eggs for 14 to 17 days until they hatch. Snakes and scrub jays sometimes prey on the eggs or the young nestlings.
Habitat and current distribution
The black–capped vireo currently breeds only in west–central Oklahoma, Texas, and the northeastern Mexican state of Coahuila. It is believed the bird winters in central and western Mexico, but biologists (people who study living organisms) are unsure.
Approximately 300 vireos exist in Oklahoma and 3,000 in Texas. Results of population surveys in Mexico have been questionable: some list fewer than 30 birds, but others list over 9,000.
The black–capped vireo requires a very special nesting habitat. It nests in shrubs on rocky slopes or eroded banks in areas between forests and grasslands.
History and conservation measures
The black–capped vireo once bred throughout the south-central United States. Over the years, much of the bird’s habitat was converted into farms and urban areas. Other portions of its habitat were destroyed by the overgrazing of cattle and other livestock.
The changing of natural habitat by humans has affected the black–capped vireo in another serious way. The brownheaded cowbird normally inhabits grasslands and prairies. As its habitat has been taken over by humans, it has had to expand its range into that of the black–capped vireo. The cowbird likes to lay its eggs in the nests of smaller birds, such as vireos and sparrows.
Once the cowbird nestlings hatch, they compete with the other nestlings for food from the new parents. Many times, the smaller nestlings die from starvation. In some areas, this type of behavior, called parasitism (pronounced pair–a–si–TIZ–um), occurred in over 90 percent of black–capped vireo nests.
Recently, scientists have discovered that South American fire ants, accidentally brought into the black–capped vireo’s range, are preying on the bird’s nestlings. The ants attack the nest and devour the nestlings within the course of a single night.
Current conservation measures on behalf of the vireo include controlling the cowbird population and protecting the vireo’s habitat. A National Wildlife Refuge is being established outside of Austin, Texas, to maintain a habitat specifically for the black–capped vireo.
The black–capped vireo (pronounced VEER–ee–o), also called the black–capped greenlet, is a small songbird that averages about 4.7 inches (12 centimeters) in length. The color of the male’s plumage (covering of feathers) is dull yellowish–green above and whitish below.
The female is slightly darker above with yellowish underparts. The head is black in the male and gray in the female. Both have white eye markings. The bird forages in leaves and branches for insects, spiders, fruit, and seeds.
A female black–capped vireo lays a clutch (eggs produced at one time) of 3 to 5 eggs in a rounded nest made of vegetation. Both the male and female take turns incubating (sitting on or brooding) the eggs for 14 to 17 days until they hatch. Snakes and scrub jays sometimes prey on the eggs or the young nestlings.
Habitat and current distribution
The black–capped vireo currently breeds only in west–central Oklahoma, Texas, and the northeastern Mexican state of Coahuila. It is believed the bird winters in central and western Mexico, but biologists (people who study living organisms) are unsure.
Approximately 300 vireos exist in Oklahoma and 3,000 in Texas. Results of population surveys in Mexico have been questionable: some list fewer than 30 birds, but others list over 9,000.
The black–capped vireo requires a very special nesting habitat. It nests in shrubs on rocky slopes or eroded banks in areas between forests and grasslands.
History and conservation measures
The black–capped vireo once bred throughout the south-central United States. Over the years, much of the bird’s habitat was converted into farms and urban areas. Other portions of its habitat were destroyed by the overgrazing of cattle and other livestock.
The changing of natural habitat by humans has affected the black–capped vireo in another serious way. The brownheaded cowbird normally inhabits grasslands and prairies. As its habitat has been taken over by humans, it has had to expand its range into that of the black–capped vireo. The cowbird likes to lay its eggs in the nests of smaller birds, such as vireos and sparrows.
Once the cowbird nestlings hatch, they compete with the other nestlings for food from the new parents. Many times, the smaller nestlings die from starvation. In some areas, this type of behavior, called parasitism (pronounced pair–a–si–TIZ–um), occurred in over 90 percent of black–capped vireo nests.
Recently, scientists have discovered that South American fire ants, accidentally brought into the black–capped vireo’s range, are preying on the bird’s nestlings. The ants attack the nest and devour the nestlings within the course of a single night.
Current conservation measures on behalf of the vireo include controlling the cowbird population and protecting the vireo’s habitat. A National Wildlife Refuge is being established outside of Austin, Texas, to maintain a habitat specifically for the black–capped vireo.
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