Oology – The Study of Bird Eggs

June 7, 2011 by  
Filed under Features

Oology can have two meanings. It is used to either refer to the study of bird eggs, or it can be used to describe the collecting of bird eggs. Even though the name is the same, the impact on bird life and ecosystems is vastly different. Studying bird eggs allows scientists and conservationists to understand the breeding habits of various birds and their nests. Collecting bird eggs almost led to the extinction of many bird species, as it had become a popular hobby that is now illegal in most countries.

While practicing oology as a science, it was discovered that birds that nest and lay their eggs in bushes generally lay speckled eggs, as opposed to birds that have their nests on the ground and lay unspotted white eggs. It was also found that birds that choose trees as the ideal nesting spot have either greenish colored or blue eggs that can either be unspotted or spotted. This gives conservationists great insight into birds, their nests, amount of eggs laid and general nesting habitats of various bird species.

Collecting eggs was seen as a hobby, much like collecting stamps, during the nineteenth and twentieth century. This led to a rapid decline in birds and near extinction of some. Collectors did not just remove one egg from the nest, but the entire clutch of eggs. The rarer the bird, the more valuable their eggs became, and this endangered them even more. After the eggs were collected, they would be blown out, their contents removed, to prevent the rotting of the eggs. Egg collectors would then write a date on the egg, identify the specie and frame the eggs. It is for this reason that oology as a hobby has become illegal and in certain countries, collectors can face imprisonment.

In Britain, an overzealous oologist named Colin Watson stole the eggs out the nests of very rare and protected bird species and was fined numerous times for collecting eggs. He fell to his death from a tree in 2006, and it was revealed that he had a collection of more than two thousand eggs in his possession. Gregory Wheal, also from Britain was jailed for six months for being in possession of raven and peregrine falcon eggs, and fellow Brit, Richard Pearson had more than seven thousand seven hundred eggs, which are now protected by the law, and his detailed notes and confession described a fifteen year period of stealing eggs. Fortunately, the oology hobby became less popular and oology is now used to introduce new captive breeding methods, incubation and to save endangered species from extinction.

Cats are Number One Threat to Birds

March 29, 2011 by  
Filed under Features

According to a report by the American Bird conservancy, cats are responsible for the deaths of between 500 million to one billion birds each year in the United States. These figures include birds killed by feral and domestic cats, and many cat owners have had the experience of being presented with a feathered ‘gift’ from their furry felines. Following a study, the results of which were presented in the Journal of Ornithology, research scientist at the Smithsonian Conservation Biology Institute, Peter Marra, confirms that cats wreak havoc on bird populations in both urban and suburban areas.

Although these studies only serve to confirm what bird-lovers have known all along, that cats are enemy number one to birds, having this confirmed by scientists has been helpful in dealing with the controversy of wind-turbines and bird deaths. With the growing demand for renewable and alternative energy sources, wind turbines are getting a lot of attention. The European Wind Energy Association held its annual event in Brussels, Belgium, on 14-17 March 2011, with up to 200 top speakers addressing the more than 8,000 visitors on various issues related to using wind to generate energy. It has been reported that up to 440,000 birds are killed annually by flying into wind turbines in the United States. While the figures seems high, when compared to the number of birds killed by domestic cats alone, it becomes clear that cats pose far more danger to birds than wind turbines do.

In the study conducted by Peter Marra and fellow scientific researchers, radio transmitters were attached to fledgling Gray Catbirds in an effort to document the factors that influenced their chances of survival. The results revealed that predators were responsible for up to 80 percent of deaths among the birds being monitored, with close to half of the predators being domestic cats. Directly related to the number of cats in the area, the fledglings had a survival rate of between 20 and 50 percent. It has been shown, especially in closed ecosystems such as islands, that cats play a significant role in declining bird populations, even hunting some bird species into extinction.

The bottom line is that the leading cause of bird deaths in the United States is collisions with buildings, windows and towers, with predators being the second most common cause. While wind turbines do lead to bird deaths, this needs to be seen in relation to the value of turbines as an alternative energy source – bearing in mind that the family cat is a far greater threat to bird populations.

Study Sheds Light on Bird Collisions

March 22, 2011 by  
Filed under Features

It seems that the engineering feats of humans, such as wind turbines, telephone poles, pylons and buildings, are accidently causing the death of many birds. As birds are considered creatures with very good eye sight, we have not been able to understand why this happens so frequently. However, a closer look at how their vision works explains how most of the fatalities occur. A study done by Professor Graham Martin (Birmingham University) approached the project with the aim of understanding why these fatalities occur and to find out how birds perceive the world during flight.

Martin explained his findings saying that birds have a very unique visual system that is different to those of humans. He said: “When in flight, birds may turn their heads to look down, either with the binocular field or with the lateral part of an eye’s visual field.” This makes them blind, so to speak, in regard to the direction they are traveling in. Their frontal vision is mainly used to detect movement, and as bird’s eyes are located on the side of their heads, looking ahead is not as easy for them as it is expected to be. Their vision is at its peak looking laterally and down in search of prey.

Some birds also have another disadvantage – the speed at which they travel. Some birds have extremely fast flight speeds, making it difficult for them to react on information received, especially when sight is further complicated by weather conditions, such as mist and rain.

The study, however, is not only negative, as measures to minimize deaths can now be taken. Prof. Graham Martin stated: “While solutions may have to be considered on a species by species basis, where collision incidents are high it may be more effective to divert or distract birds from their flight path rather than attempt to make the hazard more conspicuous.” Some organizations, such as the Royal Society of Birds have already been lobbying for wind turbines to be constructed in areas that are not directly in the flight paths of birds, and conservationists are supportive of coming up with solutions to reduce bird deaths.

Migrating Birds May See Earth’s Magnetic Field

October 8, 2007 by  
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The accuracy with which migrating birds head for, and find, their chosen destination has been a source of wonder for many. Research has revealed many interesting facts over the years and many theories abound, but there is still an element of mystery that keeps scientists motivated to find an explanation.

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Austin Roberts Bird Sanctuary in South Africa

June 21, 2007 by  
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Any bird watchers planning to travel to South Africa should definitely make the effort to visit the Austin Roberts Bird Sanctuary. The sanctuary combines great food with a large habitat, which is simply brimming with birds and animals. It is the perfect place to enjoy a tasty meal while taking in the sights and sounds of nature.

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