Feather Degrading Bacteria Studied

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The existence of feather degrading bacteria in wild birds was only discovered for the first time approximately ten years ago. This natural phenomenon has therefore been plaguing ornithologists with more questions than answers and sparked the undertaking of the recent studies done to explore the effects feather degrading bacteria has on birds, and in which birds this occurrence is more common. Even though more information has been collected in regard to the bacteria, studies remain ongoing. A few interesting facts have been discovered so far.

The feather degrading bacteria seems to target brightly colored birds more than those with dull plumage. To investigate this fact, a group of scientists chose a large colony of Eastern Bluebirds living in Virginia as test subjects, studying the population as a whole and noting the differences of the bacteria found in the male and female birds. Not only does this bacteria influence the coloring of the birds, but their general health as well.

It is now known that most wild birds carry feather degrading bacteria and some birds are even host to more than one bacteria species. The exact impact the bacteria has on their feathered hosts is still unclear, but they are not found to be in the majority. Almost all the birds in the study were found to have the bacteria, which hydrolyses the protein beta-keratin. It had been found that melanin pigmented feathers are resistant to feather degrading bacteria and that the oils used by birds to preen can also halt the growth of the bacteria. These traits confirm that defenses against these bacteria can be built and it is therefore suggested that the bacteria could have an influence on the evolution of birds. It was also found that the bacteria had a greater impact on the female birds than on their male counterparts. The bacteria seems to dull the coloring of the feathers, and scientists believe that the difference in bacteria between male and female birds could be influenced by the routines followed by each sex, and the areas they travel in. It is, however, mere speculation as scientists are still trying to confirm if the daily routine of males and females could play a role in the bacteria occurrences. Alex Gunderson, from Duke University in North Carolina commented, “If bacteria detrimentally influence feather coloration, they may place selective pressure on birds to evolve defenses against them.”

Eastern Bluebird (Sialia sialis)

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The scientific name of the Eastern bluebird is the Sialia sialis. The bluebird is a small thrush and is 5.5 inches long with a narrow black bill. The bluebird found in Southwestern United States is lighter in colour than the Eastern bluebird elsewhere. You will often see the bluebird in open patches of ground like in wood edges and agricultural areas. The bluebird feeds by diving down from low branches to catch grasshoppers and other insects. Their accuracy in capturing prey is assisted by their excellent eyesight, and they can see as far as a 100 feet away.

The male is easily recognizable by its vibrant blue upper parts and its orange-red throat, breast and sides. The belly and the under tail coverts, on the other hand, are a pure white colour. The female also has blue wings and tail but the blue is just duller in colour than the males. Its crown and back are gray and it has a white ring around the eye. The female’s throat, breast and sides are brown, and like the male, its belly and under tail coverts are white. The juvenile bluebird also has dull blue wings and tail and gray crown and back. It has a white ring around the eye, but the under parts are spotted rather than white.

The Eastern Bluebird is often confused with other bluebirds because of their similar looks and coloring. The male Western Bluebird has a blue throat whereas the Eastern Bluebird has an orange-red one. The male Mountain Bluebird does not have any reddish color on its underparts, but apart from that, has similar coloring. The female birds are not as easy to separate as their male counterparts. Both the Mountain and Western Bluebirds have gray bellies and throats but the female Eastern Bluebird has a white belly and a brownish throat.

Unlike during the 1950s and 1960s, the Eastern Bluebird population has decreased alarmingly in recent years, dropping to as low as 17 percent of recorded numbers back then. Some of the reasons for this unfortunate situation include severe winters, increasing competition with other hole nesters for decreasing nest sites, and pesticides that have been used to control fire ants.

The San Diego Bird Festival

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The 12th San Diego Bird Festival, sponsored by the San Diego Audubon Society, is set to take place from 6 February through to 11 February 2008. The venue for this popular birding festival is the superb Marina Village Conference Center in Mission Bay, San Diego, California.

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Choosing the Perfect Bird House: Part 1

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In today’s world, many birds can’t find good cavities to nest in. Many of their old nesting haunts have been developed or deforested. You can help these birds by erecting birdhouses on your property.

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