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Bird Migration Influenced by Toxic Molecule

Editor — Mon, 20 Jul 2009 10:50:16 +0000

As scientists and biologists continue to struggle to discover exactly what causes birds to migrate with such accuracy, it seems new breakthroughs continue to be made. A recent discovery reported in the June Biophysical Journal sheds exciting new light on a still relatively misunderstood process of nature.

The discovery was made by Klaus Schulten (Swanlund Chair in Physics at Illinois) and his collaborator Ilia Solov’yov (Frankfurt Institute for Advanced Studies). It seems that Solov’yov did not know that the molecule known as superoxide was toxic and was using it in studies of the biomechanical process of the cryptochrome protein found in the eye of a bird. Superoxide is a toxic molecule that is known to damage cells and cause disease. Now it seems it also plays a constructive role in the process that enables birds to ‘visualise’ the Earth’s magnetic field.

It turns out that superoxide is an ideal reaction partner when paired with the cryptochrome protein. In 2000 it was discovered that this protein plays a key role in the development of a bird’s geomagnetic sense, since chemical reactions can take place in the protein in response to magnetic fields. However magnetic fields interact so weakly with molecules that up until now it was virtually impossible to understand how these reactions could take place. It was thought that changes in the electromagnetic field, such as would occur when the bird changed direction while flying, would have an effect on freely tumbling spins of electrons in the birds eye which would essentially serve as a compass that pointed north or south. Researchers then supposed that the cryptochrome recruited a reaction partner with ‘zero-spin’ and it was proposed that oxygen was that partner.

Now it seems researchers had it backwards. It may not be oxygen, but rather its close cousin superoxide, that serves as the reaction partner in this process. Initially the toxicity of the molecule caused Klaus Schulten to dismiss the idea presented by Solov’yov. But then he realized that the toxicity of the molecule was actually crucial to the role it played in the process. Most living organisms, such as birds, have mechanisms for reducing the concentrations of superoxide in the body to prevent it from damaging the organism. The molecule needs to be present – but only in low concentrations. In birds, it is the presence of this molecule that makes the biomechanical compass work effectively.

Shifting Migrations Might Indicate Global Warming

Editor — Thu, 19 Feb 2009 11:30:35 +0000

Each year thousands of citizens in the US get involved with the annual Christmas bird count. They are not professional birders, but their counts do help biologists and other researchers to get a better idea of the grand scale of things. Over time this count has revealed that almost 60 percent of migratory birds are spending their winters further north than they did forty years ago.

According to studies, the American Robin and White-throated Sparrow are just two of the 305 bird species examined which showed a dramatic northward shift in their annual migratory patterns. While this does not prove global warming in itself, it is consistent with the sort of behavior you’d expect to take place in direct reaction to a steadily warming climate. The concern is not so much for the birds themselves, but for other non-migratory bird species and animals that are left behind to suffer through the heat. Kenn Kaufman, field editor for Audubon Magazine, stressed the interdependence of everything in an ecosystem when he said about the trend: “Everything is connected. Birds are not isolated; it’s an ecosystem. It’s a system and something that happens in one area is going to affect everything else.”

While bird ranges can change for a number of different reasons, such as urban sprawl, supplemented diets and deforestation, researchers have noted that the most likely explanation for why so many different migratory birds over such a broad area are choosing to winter further north is most likely global warming. The shift is not just affecting one or two species from one or two areas – its affecting a large number of species from a large number of areas. The phenomenon is simply too widespread to be attributed entirely to only one localized cause.

So where does the report released by the National Audubon Society leave bird lovers? It refreshes in our minds the need to not contribute to the many factors causing global warming. Not only can we change our own lifestyles and encourage others to do likewise, but if we live in an area where there are non-migratory birds, we can try to be aware of their needs, providing them with food, water and shelter so that they can survive the conditions as best as possible.

Migration Flights Test Bird Stamina

Editor — Mon, 27 Oct 2008 12:29:30 +0000

It has long been known that migrating birds embark on particularly long and grueling journeys when they cross the oceans. What hasn’t been known for sure is whether or not they somehow stop along the way – until now that is. A Bar-tailed Godwit has been bestowed with the title ‘endurance champion of the animal kingdom’ after completing his epic 7,200 mile flight across the Pacific Ocean nonstop.

It’s no secret that Bar-tailed Godwits undertake an annual migration from Alaska to Australia and various islands in the southern hemisphere each year to breed. What scientists really wanted to know was if they made pit-stops along the way. That was the goal behind a recent study wherein nine Bar-tailed Godwits (Limosa lapponica baueri) were fitted with electronic tags before setting off into the sunset on their mammoth migration flights. The birds flew between 4,355 miles and 7,258 miles, depending on which route they chose to take, with their journeys lasting 6-9 days correspondingly. What makes the research particularly interesting is that the flight paths reveal the birds were unlikely to sleep during the time and even more significantly – that they did not feed along the way. That means that their wings did not stop flapping from their point of departure to their point of arrival! This makes their journey even more remarkable, since it sets new precedents for endurance in animals. According to scientists, the energy required to complete this sort of migratory journey is the greatest in the animal kingdom.

The international scientific team, under the leadership of Bob Gill of the US Geological Survey, has said: “These extraordinary nonstop flights establish new extremes for avian flight performance and have profound implications for understanding the physiological capabilities of vertebrates.” According to Theunis Piersma of the University of Groningen (Netherlands) who worked on the study, the energy requirements of the birds was the greatest known energy requirement in the animal kingdom. During their week-long, non-stop journey, the birds would have been consuming energy at around eight times their resting basic metabolic rate (BMR). This is in sharp contrast with other measurements, such as a professional cyclist who may manage to function at around five times BMR for just a few hours. Piersma appropriately summed up the results with this remark: “There is something special going on here. For a vertebrate this kind of endurance is just extraordinary.”

2008 Hummer/Bird Celebration

Editor — Mon, 21 Jul 2008 11:30:52 +0000

Every year hundreds of people gather together to celebrate the amazing migration of the Ruby-throated Hummingbird. This year will be no different and fans are getting ready to enjoy the 20th Anniversary Hummer/Bird Celebration which will take place from September 11-14.

The annual Hummer/Bird Celebration is held in the coastal Texas towns of Rockport & Fulton every September. The celebration coincides with the fall migration of these delightful little creatures but it doesn’t focus solely on the Ruby-throated Hummingbird. There are also a number of other hummingbird species present in the area around this time and bird watchers may be fortunate enough to spot Black-chinned, Rufous, Buff-bellies and Allen’s Hummingbirds during the Hummer/Bird Celebration. The main goal of the festival is to not only celebrate the annual migration of the Ruby-throated Hummingbird but to help people expand their knowledge of all birds and associated wildlife in the area. The entire event is designed to be fun, educational and inspiring and it is tailored for members of the whole family. Birders of different skill levels are well-catered for, so you can be sure that you will enjoy the weekend regardless of how experienced or inexperienced you are.

Visitors are encouraged to make the most of the 2008 Hummer/Bird Celebration, and you will find that there will be plenty of excellent speakers to keep you informed and entertained. Thus far seventeen different speakers have been booked for the event, and they will be speaking on 21 different topics. The topics are varied and will not only cover hummingbirds and birds in general, but will feature other aspects of wildlife such as butterflies and moths, as well as developing a garden that will better attract your feathered friends. Other aspects of the festival to look forward to include a bird photography demonstration, regular bus field trips, regular boating field trips, a self-guided tour of hummer homes, hummingbird banding demonstrations, hummer/bird malls where you can purchase a variety of nature-related products, butterfly walks and a number of outdoor exhibits.

After the success of the 2007 Hummer/Bird Celebration, birding fans are looking forward to an even better 2008 Celebration. Why not take the plunge and get involved by being a part of this year’s Hummer/Bird Celebration? You are unlikely to regret it!

Night Migration Mysteries Revealed

Editor — Thu, 10 Jul 2008 13:06:44 +0000

A recent study conducted by researchers from the Illinois Natural History Survey and the University of Illinois has resulted in statistical data to prove that during their nocturnal migration birds fly together in loose flocks. This is the first conclusive data that confirms what many ornithologists and bird-watchers have suspected for some time.

Researchers have spent decades attempting to unlock the mysteries of the nocturnal migration of birds. Considering the size of a bird and the altitude at which it flies, together with the fact that it is nighttime, this has proven to be very difficult. Previous studies have indicated that, although migrating birds may have been flying tens of meters apart, they nonetheless stayed together by flying at the same speed and at approximately the same altitude. However, these studies have not provided convincing proof to support this assertion. Even if a study could establish that the birds were in fact traveling together, there was no way of knowing if this flight pattern was intentional.

The new research project, which has been conducted by professor of animal biology, Ronald Larkin together with Robert Szafoni, analyzed bird-flight data which had been collected by Larkin by means of a low-power-density tracking radar during the 70s and 80s. This radar works by pointing a narrow cone, referred to as a “pencil-beam”, at any target within range. The target, in this case a bird, appears as an echo on the radar screen. With a flip of a switch, the radar locks on the target and tracks it while recording data with regard to the target’s distance from the radar, as well as its altitude and direction of flight. Moreover, the radar provides data which can be used to calculate the frequency of the target bird’s wing beats.

Once the radar has locked onto a bird and is tracking its flight, if another bird appeared in the radar’s beam, the radar operator could switch back and forth between the two birds and thereby track the flight details of both birds simultaneously. Upon analyzing dozens of sets of data, researchers came to the conclusion that a significant number of tracked birds were flying at the same speed, same altitude and in the same direction, even though some of the pairs were more than 200 meters apart.

Ongoing research continues to reveal that birds are fascinating creatures with astounding abilities – and no doubt bird-lovers everywhere agree.

Amazing Migration Survival Tactics

Editor — Fri, 27 Jun 2008 10:08:28 +0000

Ongoing ornithological research continues to confirm what keen bird-watchers have suspected all along – their feathered friends are highly intelligent and adaptive, with an amazing array of communication skills. A new study conducted by researchers at Queen’s University in Washington has revealed that migrating songbirds rely on the behavior of local resident birds to assist them in avoiding predators during migration.

Migrating birds face many potentially dangerous situations during their annual journey and sadly, many don’t make it. Avoiding predators when flying through unfamiliar territory would substantially increase a bird’s chances of arriving at its destination safely. However, to be in a position to avoid predators, a migrating bird needs to be able to establish exactly what its predators are. This is where the behavior of the local bird population proves invaluable.

The Queen’s University research project involved testing whether migratory songbirds note, and respond to, the anti-predator behavior of local birds. A common method of chasing off predators is known as “mobbing”. Once a potential predator has been identified, a number of birds will approach and rapidly change their positions around its location, while at the same time flapping their wings, twitching their tails and emitting load alarmed calls.

Recognizing that migratory birds seldom participate in mobs, researchers wanted to establish if they gain information with regard to the location, identity and degree of threat of a predator by listening to mobbing calls of local bird species. A test was carried out on birds migrating between Canada and Belize, whereby researchers broadcast playbacks of the alarm calls of the black-capped chickadee which is common in North America and therefore familiar, as well as the blue-gray tanager which is common in Central America and therefore unfamiliar to the migrating birds.

The results of this test showed that birds resident in Belize responded only to the tanager calls, whereas migrant birds responded to the tanager and chickadee calls. Queen’s University biology professor Dr. Laurene Ratcliffe, said that the results of the test present the first evidence that migrating birds take note of the anti-predator behavior of local birds during migration, and use this information to their advantage.

Birds Have Chemical Compass to Aid Navigation

Editor — Tue, 06 May 2008 10:42:53 +0000

For decades scientists have been puzzling over an intriguing wildlife mystery: how is it that birds navigate? Each year thousands of these feathered creatures make massive journeys halfway around the globe – yet exactly how they find their way to their destinations each year just boggles the mind.

Until recently, there were two theories with regard to this amazing natural phenomenon in bird species. The first is that birds have tiny particles in their upper beaks. These particles, called magnetite, respond to shifts in the Earth’s magnetic field. The theory was credible and proved by research done with homing pigeons four years ago. The second theory, however, was still unsubstantiated. This theory revolved around the idea of a photochemical compass. It was thought that a protein, which was triggered by light through the bird’s eye, responded to magnetism thus providing a guiding compass that they could navigate by. This theory was considered to be weak since no one knew of a molecule that could respond to the Earth’s geomagnetic force so sensitively. However Oxford University has recently given weight to this concept by creating a compound that shows that this sort of chemical compass is possible.

Though this compound has thus far only been made and tested in a laboratory, it links the two biological pigments known as carotenoid and porphyrin with a carbon molecule known as fullerene. The process starts when a burst of light is used to excite the compound, resulting in the creation of ‘radical pairs’ of electrons. These each have a property called spin and research has shown that a magnetic field can cause the spins to become aligned. In theory, when the Earth’s gravity aligns these spins in the bird’s built-in compass, it most likely triggers a biochemical reaction that tells the bird what it needs to know about the magnetic field and helps direct it to its destination.

To scientists the new research is proof that the concept is possible. It also ties in nicely with previous research and it is thought likely that this is just one aspect of a complex navigational system that is commonly used by birds. However the debate is not over yet as it is still not known how the bird’s brain would be able to receive these informative signals and interpret them. Theories abound regarding this but have yet to be proven and properly understood.

International Migratory Bird Day 2008

Editor — Tue, 01 Apr 2008 13:18:04 +0000

As part of their drive to increase awareness of birds and the need for conservation across the Western Hemisphere, Environment for the Americas hosts International Migratory Bird Day. Each year a different conservation-based, educational theme is chosen for International Migratory Bird Day. The theme chosen for 2008 is “Tundra to Tropics: Connecting Birds, Habitats and People”. This theme is carried through on educational materials and art, as well as promotional posters and t-shirts, nurturing a sense of solidarity among birders irrespective of where they may be based.

Created in 1993 by forward-thinking individuals at the Cornel Laboratory of Ornithology and the Smithsonian Migratory Bird Center, International Migratory Bird Day has evolved into Environment for the Americas’ principal education project. The focus of the event continues to be on the epic journey of migratory birds between their summer and winter habitats, as well as what needs to be done to conserve their vital en route and destination habitats, thereby conserving the birds themselves. Bird lovers from across Canada, United States, Central America and Mexico are encouraged to get involved with this project.

International Migratory Bird Day officially takes place each year on the second Saturday in May and the 2008 official date is 10 May. However, bearing in mind that to the south migratory birds have not yet started their journey and to the far north the birds haven’t arrived yet, International Migratory Bird Day stretches out through the year while remaining focused on the current theme. In the United States and Canada, the majority of events take place during April and May, while in the Caribbean and Latin America events generally take place in the autumn months.

Events for International Migratory Bird Day celebrations can include anything from a morning bird walk to a multi-day festival. The organizers have made available fact sheets, posters, coloring-in pages, a press kit and numerous activity suggestions. The extensive promotional and educational material provided by Environment for the Americas are not dated and can be used throughout the year for all organized events. Participants in an International Migratory Bird Day bird count can make a significant contribution to conservation efforts by submitting their data to the organizers and thereby becoming citizen scientists.

The annual migration of birds is a highlight in any bird watcher’s calendar. The International Migratory Bird Day creates a theme around which birding clubs and organizations can build their events. This often encourages newcomers to join seasoned birders in exploring the many marvels of bird life.

Migrating Birds May See Earth’s Magnetic Field

Editor — Mon, 08 Oct 2007 13:47:33 +0000

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.

For many years scientists have believed that migrating birds have an internal compass to navigate between their wintering grounds and their nesting areas, which are very often thousands of kilometers apart. Much as a compass that humans use, this internal compass was thought to be strongly influenced by the earth’s magnetic field, but it was not understood which part of a bird’s brain or sensory system was used.

More recent research suggests that a migratory bird’s eyes contain molecules which sense Earth’s magnetic field. These molecules are linked to the area of the bird’s brain that processes visual information. So, the possibility exists that bird species may actually be able to see the Earth’s magnetic field. Research involved injecting migratory garden warblers with a special dye, which can be traced along nerve fibers. The research team injected tracer dye into the bird’s eyes and also into a region of the brain, which is most active when birds orient themselves, known as Cluster N. When the subjects of the experiment got their bearings, both these tracer dyes traveled to the thalamus, which is a region in the middle of the brain responsible for vision, proving that there is a direct link between Cluster N and the eye. Results of this research strongly support the theory that migratory birds use vision of the magnetic field to navigate.

Scientists, not involved in this particular study, have cautioned that these new findings are the not the final pieces of the puzzle of navigation over long distances. A compass can tell you in which direction north, south, east and west are, but that is of no use if you don’t know where you are, therefore a map is also necessary. One researcher has suggested that birds may have magnetic crystals in the bills which sense the intensity of the magnetic field, thereby establishing their physical location.

Certainly scientists are a few steps closer to unraveling the mystery of what guides birds during migration. Nevertheless, the mystery is not solved yet.

Eurobirdwatch 2007 across Twenty-Eight Countries

Editor — Wed, 03 Oct 2007 10:17:32 +0000

Millions of birds leave Europe during the month of October as they undertake their migratory journey southwards to warmer regions. On the 6th and 7th of October 2007, national organizations affiliated to BirdLife International in twenty-eight European countries will be participating in Eurobirdwatch 2007. In most countries, organizers will be setting up information and observation posts where bird-watchers can observe the birds, interact with fellow bird-lovers and learn more about nature, focusing on the mysteries of migration.

For migrating bird species the continued existence of breeding areas in the north, stopover points along their flight path and suitable nesting grounds in the wintering regions are issues which affect their very survival. BirdLife International and their partners in Europe are attempting to bring to the attention of the public that the variety and beauty of birds serve as reliable indicators of the state of our environment. If people are encouraged to connect with birds, they may be motivated to take care of nature and natural resources – to the benefit of birds and humans.

Eurobirdwatch 2007 is being coordinated by SVS/BirdLife Switzerland. They will process the data sent to them by the national centers in the various participating countries. Data includes a count of the number of people participating, as well as a record of the species of birds observed and the number. In previous years approximately 40,000 people participated and up to three million birds were observed during a single weekend.

Of the twenty-eight countries participating, some have put in extra effort to achieve their goal of educating the public about birds. In Gibraltar, the Gibraltar Ornithological and Natural History Society has organized events centered on the Alameda Gardens and the Europa Point Marine Observatory. Activities will include bird ringing demonstrations and static and flying displays of birds of prey. Visitors will also be able to view the eagles, hawks, falcons and owls at the rehabilitation centre. The Wildlife Park will have an open day, which will give visitors the opportunity to view exotic birds, and animals that have been confiscated, as well as others that are kept for educational and breeding purposes. A Bird Quiz will take place and winners will receive nature books as prizes. Latvia has organized a “Let’s Run After the Birds” competition in Kemeri National Park and will be launching a new booklet “How to Start Bird-Watching”. Slovakia is getting school children involved with activities including making nest boxes, painting and photography of birds.

Eurobirdwatch 2007 gives bird enthusiasts throughout Europe an opportunity to enjoy the wonders of annual bird migration along with fellow bird-lovers – don’t miss out!