Herald Petrel (Pterodroma arminjoniana)

February 9, 2009 by  
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The Herald Petrel (Pterodroma arminjoniana) is a medium-sized bird belonging to the Procellariidae family. It is a sea bird and spends much of its life on or above the ocean, only really visiting nesting grounds during breeding season. It is generally found below the Equator but you may find these birds as far north as North Carolina on occasion. One of their more notable breeding grounds is that of Raine Island and other small cays in the Coral Sea where it can forage comfortably in the surrounding ocean. When looking for breeding grounds, the Herald Petrel favors warm islands with soils that are well suited for nesting burrows. It feeds on squid and crustaceans which it skims from just below the surface of the water with its bill only to be ingested later whilst the bird is in flight.

When you look at the Herald Petrel, you will find that its body measures roughly 36-41 cm in length with a wingspan of 97-102 cm. Generally speaking, the whole bird is gray with some green showing on the nape and upper tail. The body has no patterning whatsoever. The Herald Petrel also has a hooked, seabird-shaped bill and a pointed tail. The wings are also quite pointed in shape while the legs are pink in color. Birdwatchers should note that there are three different color morphs of the Herald Petrel: light, intermediate and dark. The light morph has a white chest and belly, while its upper parts are a dark gray. The dark morph has a dark grey body overall with a silver-grey or white base on its under-wing flight feathers. The intermediate morph is mixture of the light and dark morph.

When the time comes for the Herald Petrel to breed, both sexes will work together to excavate or clean out a burrow. Once this is done, the female lays only one egg in a sparse, un-lined burrow and both the male and female share incubation duties. After 49-54 days, the eggs hatch and a new Herald Petrel is born. Herald Petrels have only one brood a year.

Manx Shearwater (Puffinus puffinus)

February 9, 2009 by  
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The Manx Shearwater (Puffinus puffinus) is part of the Shearwater family and is extremely distinctive from his counterparts. It is a medium sized Shearwater and is 34 centimeters in length, with a wingspan of 81 to 86 centimeters. It is the coloring of the Manx Shearwater that makes them easy to identify. The upper body parts, such at the head, neck, back and the upper part of the wings, are gold in coloring and the plumage is brown to black. Their throats, bellies and under wing areas are white. Their hooked shaped bills are black, with the tail and eyes also being dark in color. The Manx Shearwater forages for food on the surface of the water, but also dives to find fish, mollusks and shellfish.

In the winter months the Manx Shearwater migrates to the coastal areas of South America, and during the breeding season they are found in the United Kingdom, specifically on the island of Lundy. Most of the world’s Manx population migrates to Lundy to breed, and the conservation of these birds is top priority. The conservation has reached a point of urgency, as the 1000 breeding pairs that were recorded in 2001 have declined to 166. This dramatic fall in numbers is a major concern, and the island is currently working on managing the rat population, as they are responsible for many of the eggs being destroyed. The birds start arriving at night during the months of February and March. Burrows and rock crevices on top of the slopes are used for nests. The female Manx Shearwater lays only one egg that is black and orange in color. Both the male and female are responsible for the incubation of the eggs that lasts approximately 52 to 54 days. The chicks are ready to fledge the nest in September, but remain very near to the breeding colony until October.

The Calf of Man, a small island just off Isle of Man, has seen an increase in the number of breeding pairs after the removal of many of the rats that were accidentally introduced to the island by a shipwreck. The oldest Manx Shearwater that has been recorded was aged 55. After being tagged at the age of five in 1953, the bird was trapped again in 2003, alive and well. An ongoing Manx Shearwater conservation project on the Isle of Rum ensures that baby birds get a fighting chance to make it to adulthood.