Mute Swan (Cygnus olor)

February 9, 2009 by  
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The beautiful Mute Swan (Cygnus olor) is the bird that people most commonly picture when discussing a swan. This striking, white bird with its slender neck, black eyes and dark orange bill has become a bird of legend, with many European and Asian fairytales and bedtime stories featuring this magnificent creature. The Mute Swan is found naturally in the more temperate parts of Europe and western Asia and, while it is not migratory as such, certain inland populations are forced to move to the coast in winter when their waterways and lakes may freeze over. Because these birds are considered to be so beautiful, some have been taken to other countries where attempts have been made to keep them at parks and ponds. However, the birds inevitably escape and as a result there are currently a number of feral bird populations in the US which have become naturalised over time. In some places, however, they compete with local bird species for food and space resulting in them being labelled as ‘pests’. Nevertheless, they fall under the AEWA conservation agreement.

The Mute Swan is an impressively large bird with an average body length of between 145-160 cm. Their wingspan may measure 208-238 cm in length and the males are normally quite a bit larger than the females. These proportions and the resulting weight make the Mute Swan one of the heaviest flying birds in the world and the heaviest water bird ever recorded. Both the cobs (males) and pens (females) are similar in appearance with pure white bodies, necks and heads. There is a small black area around their eye which joins up with the knob on their bills. The males have a larger knob than the females. Their bills are orange-red in color and their necks have an unmistakable S-like curve which adds greatly to their allure. Young Mute Swans are called ‘cygnets’ and they are normally a dull white or grey with a dull-colored bill.

Mute Swans usually build their nests on large mounds which they create in shallow water. These mounds may be either in the middle or near the edge of a lake. The birds typically use the same nest each year and they may have to restore or rebuild it at the beginning of breeding season. The Mute Swan is monogamous and both sexes share in building and caring for the nest and for incubating and raising their young. Mute Swans normally feed on water plants, insects and snails and an adult may eat as much as 4 kg of vegetation in one day. These birds are generally found in large colonies and can become quite tame though they will always act defensively if you approach their nest and it is not recommendable for anyone to do so.

Neotropic Cormorant (Phalacrocorax brasilianus)

February 9, 2009 by  
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Most commonly found in the American tropics and subtropics, the Neotropic Cormorant (Phalacrocorax brasilianus) is a fairly large bird that generally nests around well-watered areas or lakes and rivers. Besides being found on the mainland of North America as far up as Rio Grand and the Californian coast through to Mexico, Central America and the southern parts of South America, it can also be found on smaller landmasses such as the Bahamas, Cuba and Trinidad. Most of these birds are permanent residents, though some do wander north in the warmer months. Because the bird is so widespread, some ornithologists prefer to treat those found north as one species and those found in the south as another species. However, they can also be grouped into the subspecies Phalacrocorax brasilianus mexicanus (the northern birds) and Phalacrocorax brasilianus brasilianus (the southern birds) and the two are therefore often grouped together as one species of cormorant. The Neotropic Cormorant was formerly known as the Olivaceous Cormorant.

Neotropic Cormorants usually have a body length of 64 cm with a wingspan of 100 cm. They can weigh between 1 and 1.5 kg and those found in the south are usually bigger than those found in the north. Neotropic Cormorants are somewhat slender compared to other cormorants and they have a long tail, hooked bill and long, thin neck, which it frequently holds in an S-shape. The Gular region is pointed and dull yellow in colour and there is a thin pale border around this area. The adult bird has dark plumage covering its entire body, though the throat becomes whiter during breeding season with white tufts appearing on the sides of the head. Immature Neotropic Cormorants have dull brown upperparts and pale underparts.

The Neotropic Cormorant is somewhat different from other cormorants in that it often perches on wires. When it does perch, it is usually with wings spread wide open to dry. These birds feed mainly on small fish and also eat tadpoles, frogs and aquatic insects. They obtain their food by diving underwater and using their feet as a means of propulsion. The Neotropic Cormorant may also forage in groups, beating their wings in the water to drive the fish into the shallows. When it comes to mating, the birds are monogamous and they breed in colonies. They usually build their nest out of sticks in a depression. The centre is usually lined with twigs and grass and cater to as many as five eggs. Both parents sit on the eggs for a period of 25-30 days and then both work together to feed the young until the chicks reach independence at 12 weeks of age. Neotropic Cormorants raise only one brood a year.

Rose-breasted Grosbeak (Pheucticus ludovicianus)

February 9, 2009 by  
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The Rose-breasted grosbeak or as it is scientifically called, Pheucticus ludovicianus, is about 7.25 inches long and has a large, cone shaped, pale colored bill. The female grosbeak looks similar to the female-plumaged Black-headed grosbeak but has an orange-brown breast with streaks only on the side of its body. The Grosbeak lives near open woodlands that are near to water. It also likes thick brush or small trees, large trees, marsh borders, gardens, parks and overgrown pastures.

The adult male Rose-breasted Grosbeak has a rose red, triangular shape patch on its white breast. The upper parts of its body and head are all black and the under parts are white. The wings have white patches and are lined with rose red. His black tail feathers are speckled with white spots. In winter and autumn the male becomes browner and dull in colour. The juvenile bird has a similar coloring to the male’s winter and autumn colour.

The adult female Grosbeak has black and white stripes on its crown above its eyes. The under parts of the bird are white with extensive streaking, whereas the upper parts are a dark grey. Where the male has a rose red lining the female has a more yellow to yellowish-orange wing lining. The juvenile has an orangey-brown breast and the juvenile female has similar coloring to the adult female.

The Grosbeak mating system is monogamous and so the male and female will pair off and have between three to five pale green, blue eggs. During the courtship the male will fly after the female while singing to her; he will then crouch down and spread and droop his wings; spread his tail, withdraw his head with his nape against his back; once in position he will start singing and waving his head and body in an erratic dance.

The cup-shaped nest is made up of loose twigs, rough plant material and then lined with thin twigs, hair and rootlets. The nest is normally 5-15 feet above the ground and is built by the female with help from the male Rose-breasted Grosbeak. The incubation of the eggs takes up to two weeks and will be looked after by both the male and female bird. The development of the chicks is altricial, which means that they are immobile and eyes closed. Once the young hatch it takes just less than two weeks before they will leave the nest.

Roseate Spoonbill (Ajaia ajaja)

February 9, 2009 by  
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The male and female Roseate spoonbill, Ajaia ajaja, is 28 inches long and has a wingspan of 53 inches. They are relatively large, long-legged waders and have a long neck and a long spatula-looking bill. When the Roseate spoonbill is in flight it holds its neck extended.

The adult bird has red eyes that are in contrast to its greenish, featherless head. The bill is gray in color with dark mottling and it has a black nape band. The wings and back of the spoonbill are a beautiful pink color, the legs are red and the feet dark. The juvenile spoonbill has yellow eyes and bill with a white or at times a pale pink plumage and a white-feathered head.

The Roseate spoonbill enjoys marshes, mangrove swamps and tidal ponds found along the Gulf Coast. They feed in water that is shallow, brackish or salty and at times they will feed in fresh water by swinging their spoon-shaped bill from side to side in long arcs. The spoonbill will feed either in small groups or by themselves and are often seen in company of other varieties of wading birds.

The Roseate spoonbill is a monogamous bird and will breed in swampy, marsh areas producing one brood. Their nest is made up of dense vegetation above the water or on ground. The nests are made well and are a cup shape stick platform, lined with dry fine materials. The male spoonbill will look for the building materials while the female builds the nest. The female will produce three off-white eggs, marked with brown. The incubation period takes just over three weeks and once they hatch it takes a further 35 to 42 days before they are able to fly. The spoonbill’s diet is made up of fish, insects, crustaceans and a few water plants. They pick up the food by sweeping their bill through the water and when they feel their food they snap it up. The nesting area or colony is made up of different birds, like herons and egrets.