Archive for the ‘Birding News’ Category

Plastics at sea: an emerging concern for seabirds and, some tidbits of exciting good news!

April 3, 2011

Taken from: biology-blog.com

One of the consequences of being up-to-date on conservation news is that you are frequently bombarded by bad news. For that reason, after reporting on a new concern for seabirds I will also report on a couple of good-news stories for them from late February and early March. First things first, last year’s World Seabird Conference highlighted the issue of massive amounts of floating and suspended plastic debris in our oceans and the dangers they pose on birds who consume them. One such swirling mass of plastic is off the coast of BC, and is coined the Great Pacific Garbage Patch. This particular collection of plastic is trapped in the North Pacific Gyre, which is one of five circular currents in the ocean. Waste plastic does not degrade in the ocean, and instead is ground down into ever-smaller particles suspended in the water. Estimated to be roughly twice the size of Texas, this mass is therefore not the huge island of flotsam that it is popularly characterized to be, but is instead a concentration of plastic particles suspended in the upper water column. The source of the garbage is largely speculation, but it is suspected that up to 80% of it comes from land and not from ships dumping garbage overboard. Another unusually large congregation of plastic debris is trapped within the North Atlantic Gyre, the North Atlantic Garbage Patch.

Aside from being startling in general, the larger bits of trash are sometimes mistaken for food by pelagic birds. Researchers have found remains of Albatross chicks that died because they were fed bits of plastic by their parents that eventually clogged their digestive systems. Albatrosses seem particularly prone to swallowing larger plastic items, and many birds may get tangled in plastic debris floating on the ocean’s surface. Smaller confetti-like pieces may be consumed and resist being passed by digestive systems. This may have the effect of decreasing hunger and reducing digestive efficiency, which may cause weakness and death in birds. Tiny bits of plastic pose a threat to birds in more subtle ways. As the plastic is ground into smaller and smaller bits, it is eventually small enough to be consumed by tiny organisms living close to the water’s surface. As these organisms are eaten, and those consumers are themselves prey to something larger, and so on, these particles become concentrated. The particles then pose risks by leaching toxins into the animals that consume them. One recent research project at the University of British Columbia in Vancouver, Canada, catalogued the stomach contents of birds that washed up on beaches in western Canada in 2009. Plastic was found in the stomach of all of the 36 Northern Fulmars examined except for one. It is estimated that people in North America use around 100 kg of plastics per year per person. We can all do our part by recycling as much of our usage as possible, and supporting programs to deal with existing trash in our oceans.

As promised: two great pieces of news. A 60-year-old Laysan Albatross was recently sighted in Hawaii. The bird, known as Wisdom, had been banded in 1956 and last resighted in 2001. Her rediscovery this year makes her the oldest known wild bird. The observer, John Klavitter, of the US Fish and Wildlife Service, also reported that she was in the company of a new chick! AND, a new species of Storm-petrel, the Puerto Montt Storm-petrel, was discovered off the coast of Chile in February. Further details are forthcoming!

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Northern Flicker

March 20, 2011

Photo credit: Utahbirds.org

The Northern Flicker (Colaptes auratus) can be described as a veritable patchwork of other bird’s parts. This species possesses the spots of a starling, the clay-colored plumage and ground-dwelling behavior of a Mourning Dove, the red nape of a woodpecker, and the feeding habits of a Jay. Northern Flickers also come in two color morphs: the salmon-pink “red-shafted” in the western U.S. and the vivid “yellow-shafted” in the eastern part of the country. While this bird’s appearance seems to be clownish and confused, its unique characteristics allow it to thrive.

Flickers are known for their odd fondness for the ground – not many woodpeckers would choose soil over sycamores. When on the ground, flickers are searching for insects, especially ants. These birds can be observed digging through leaves and debris and flipping over bits of wood to find insects, which it licks up with its barbed tongue. Flickers will also feed on seeds, nuts, grains, and acorns.

Northern Flickers are strongly migratory, and individuals in the northern part of North America will migrate south. In summer, the birds can be found as far north as northern Canada and inland Alaska, but in winter the birds move south into Texas, the American southwest, and the Caribbean. A hybrid zone exists where the range of the yellow-shafted and red-shafted morphs overlap in the western U.S. Studies have shown that the birds will readily breed with individuals of the opposite color, and show no preference for their own color morph.

Courtship displays involve energetic calls, territorial drumming, bobbing, and wing and tail displays. Male birds can be distinguished from females because of their red or black “moustache.” Yellow-shafted males have black patches on each side of their beak; Red-shafted males have red patches. After mating takes place, the male bird will usually choose a nest site, generally in a hollow snag or tree hole. The male and female bird will work together to enlarge and prepare the nest, a process that averages 12 days. Flickers will occasionally oust kingfishers or Bank Swallows and take over their nest burrows in streambanks. A male may return to the same nest site for several years. Female flickers will lay 5-8 inch-long white eggs on top of a nest lining of fine wood chips. Uniquely, two females may share the same nest, laying eggs that they will then take turns incubating.

 

After a two-week incubation period, the featherless altricial chicks hatch. Chicks are fed regurgitated food by parents until they fledge approximately one month after hatching. Northern Flickers have been known to hybridize with Gilded Flickers, which are native to desert areas in the southwest U.S.  Originally thought to be the same species as the Northern Flicker and difficult to distinguish from its northern cousin, the Gilded Flicker was declared a separate species because of the fact that the species only occasionally hybridizes with Northern Flickers even though the two species’ ranges overlaps extensively.

Northern Flickers are common and widespread in the U.S., but their population is declining. To attract flickers to your yard, offer suet and fruit-bearing shrubs, and avoid applying pesticides that can kill insects and harm the birds.

 

Whooping Crane

March 14, 2011

taken from katc.com

At five feet (1.5 meters) tall, the Whooping crane (Grus americana) is the tallest bird in North America, and also one of the rarest. Whooping cranes are named for their distinctive whooping call, and can be distinguished from their relatives, Sandhill cranes, because of their snow-white plumage and bright red cap. Whooping cranes can live to be more than twenty years old in the wild.

The cranes feed and breed in freshwater wetland and taiga ecosystems in very limited and isolated regions of North America. The only known nesting location for these birds is Wood Buffalo National Park in northern Alberta, Canada. Conservation efforts have succeeded in reintroducing the whooping cranes to the Necedah National Wildlife Refuge in central Wisconsin, where they have begun breeding for the first time in nearly a century. In winter, whooping cranes can be found along the Gulf coast of Texas, and during migration the birds congregate at a stopover point in Oklahoma, the Salt Plains National Wildlife Refuge.

Whooping cranes forage for food in shallow water or fields using their long, thick bill. The birds are omnivores, but tend to prefer animals to plants. Their diet includes snails, crustaceans, insects, frogs, fish, small reptiles, aquatic tubers, small rodents, berries, and fallen grain.

During the breeding season, these large birds engage in energetic and elaborate courtship dances. The birds can be seen leaping about with wings spread, tossing their heads, and throwing small objects back and forth. The birds possess a uniquely coiled trachea that increases the volume and pitch of their haunting calls. After breeding commences, new pairs of birds will often choose a home territory near that of their parents, a feat that is not difficult, owing to the limited breeding range for these birds. Whooping cranes nest on the ground. Adults build a raised platform out of marsh vegetation and the female lays 1 to 2 eggs between late-April to mid-May. The blotchy, olive-colored eggs are approximately 3 inches long. Both parents share incubation duties, which lasts about a month. Generally, no more than one chick survives, even though both parents tend to the young. The chick will often remain with its parents for nearly one year before venturing off on its own.

 

Extensive conservation efforts have been underway for many years. The crane was declared endangered in 1967, and since then efforts have been made to establish captive and wild breeding populations. Because the cranes are highly migratory, scientists faced the immediate challenge of teaching young birds to migrate. One of the most successful projects, called Operation Migration, overseen by the Whooping Crane Eatern Partnership, involved training a flock of young cranes to follow an ultralight aircraft on a new migration path east of the Mississippi. The project began in 2001 when birds that hatched in Wisconsin were taught the route to Florida. This population of birds, known as the Eastern Migratory Population, has grown each year, and now stands at 52 individuals. The worldwide population of Whooping cranes is approximately 460 birds, with nearly half living in captivity.

Birds as Parasites? A Different Way to Make a Living

March 9, 2011

Photo credit: Philip Colla

When people think of parasites, mosquitoes sucking blood or nasty worms are usually the first creatures that come to mind. However, many different types of animals, plants, and fungi can be parasites. In the case of birds, some species have developed a unique nesting strategy; or, rather, an anti-nesting strategy. These species are called brood parasites and they make their living by laying their eggs in the nests of other birds. Some brood parasites are opportunists and will usually build their own nest and raise some young, but will also try to sneak an egg or two into a neighbor’s nest. Waterfowl and colonial species like swallows are often found in this category. Other brood parasites, like the Brown-headed Cowbird, never build their own nest. They solely depend on other species to raise their young. These birds are known as obligate brood parasites.

The hosts of these parasites are often negatively affected by the presence of the foreign egg or offspring. Brown-headed Cowbird chicks usually hatch out sooner, grow more quickly, and are larger than the host chicks. Thus, they are usually able to outcompete the host chicks for food. The Common Cuckoo in Europe has a different strategy. Cuckoo chicks usually hatch first and then, soon after hatching and still blind, proceed to remove everything left in the nest, thereby completely eliminating all possible competition. In Africa, Honeyguide chicks use sharp hooks on their beaks to kill their unrelated nest mates. In addition, female cowbirds and cuckoos will often remove one host egg before or after laying their own, automatically reducing the number of host offspring that can hatch.

All this devious behavior begs the question: if brood parasitism causes such harm to a host’s nestlings, why would the parent allow this behavior to occur? Why not toss the foreign egg out of the nest or try to prevent the parasite from laying its egg in the first place? This question has been studied intensively for years and, in some aspects, still remains a mystery. It is not well understood why a Reed Warbler, a common host of the cuckoo, will stand by and watch as its own young or eggs are removed from its nest by a newly hatched cuckoo chick. Likewise, it is bizarre that a Wood Thrush laying blue eggs should sit on a Brown-headed Cowbird egg that is white with brown spots and then raise the chick as if it were its own.

However, it is not all “doom and gloom” for the host. Some hosts are able to remove foreign eggs, though most do not remove foreign chicks. The Yellow Warbler has a tendency to bury cowbird eggs inside nest lining. Some hosts desert parasitized nests and start over elsewhere. Others may try to build a nest in dense vegetation to reduce their chances of being parasitized. Nevertheless, the great number of hosts that do not exhibit any defenses towards brood parasites remains an interesting enigma that scientists are still trying to unravel.

Friday Pulse: Flood Concerns Increase, And A Robin?

March 4, 2011

Good news or bad news first? Okay, the good news…

A large flock of robins were spotted in the trees across from the Wyalusing State Park park office, near the bird feeders. Spring cannot be far behind.

However (cue the bad news music), spring is likely to bring major flooding. The latest predictions give us a 86% chance of a flood comparable to the one in 2001, the second highest in Prairie du Chien history. 1965′s record flood has a 70% chance of being matched this year.

Read more here.

The American Birding Association Code of Ethics

March 1, 2011

Many sports, outdoor activities, and hobbies have a code of ethics, be it formal or passed on by word of mouth or gradual indoctrination by more experienced participants. Such codes exist for a variety of reasons including safety, consideration for others, respect for the facility or the environment, and preservation of the sanctity and continuation of the activity, among others. It may come as a surprise to beginning bird watchers that there is a serious code of ethics to which participants are expected to adhere.

The American Birding Association (ABA) has outlined a clear and logical code of ethics for bird watchers to help ensure the most positive experience in every birding situation and help secure the activity from negative criticism by non-birders who share a love of the outdoors. The code even addresses the responsibilities of bird feeding enthusiasts because they are an important demographic of the birding community as a whole. Of course no one is forced to adhere to any code of ethics, but if you rub most serious hobbyists the wrong way by intentionally violating the code, you can probably expect some very heartfelt backlash.

 

There are four key parts, each of which is quite general but has several more specific subparts, to ABA Code of Ethics. The first part of the code is to “Support the welfare of birds and their environment.” That is pretty self explanatory, but also very general. The ABA suggests an ethical birder should be on board with things such as protecting habitat, not stressing out birds by chasing them through the bush, cutting new trails and damaging habitat, or pishing at them until you are out of breath. Nor should you engage in the excessive use of cameras and playback, and always be sure to keep a respectable distance from nests, roosts, and crucial foraging spots. The second part o the code is to “Respect the law, and the rights of others.” By this the ABA means that you should not trespass, break any laws of the road, or violate trail rules in public areas. Furthermore, you must respect the rights of others to be in the same area as you, which means it is your duty to display common courtesy for other birders and anyone else engaging in legal outdoor recreational activities. The third part of the code is to “Ensure that feeders, nest structures, and other artificial bird environments are safe.” Basically if you do anything to try and entice birds to be closer to where you reside, you are obligated to keep all artificially created bird environments sanitary and not unnecessarily expose your visitors to unnatural dangers, like cats or other domestic animals. The fourth and final part of the code states quite simply that, “Group birding, whether organized or impromptu, requires special care.” This one is a little more complicated, but essentially addresses such things as respecting your birding partners, limiting your group size, and leading by example by being helpful to others and always following the birding code of ethics.

If you would like to familiarize your self with the all the details of the American Birding Association Code of Ethics, which you really should if you aspire to be a good and responsible birder, it is available in “About ABA” section of their website or by following the following link directly http://www.aba.org/about/ethics.html.

 

New Research Finds That Pigeons Navigate By Smell

February 25, 2011

Photo credit: petcaregt.com

The ability of birds to navigate over incredibly long distances has fascinated people for hundreds of years. There is a body of evidence showing that an individual bird has the ability to migrate across hemispheres and return next spring to the very same tree where it was marked the previous year. John James Audubon conducted one of the earliest experiments in this area of research in 1803 when he tied a bit of thread to the leg of an Eastern Phoebe at his home in Pennsylvania before it migrated to some unknown location in the southern United States. He then observed the same bird on his property the following spring and like so many others wondered how a bird could achieve such a feat of navigation. Our current understanding suggests that birds navigate according to a variety of ways and means, including the position of the sun and stars, visual landmarks, bands of polarized light in the atmosphere, the magnetic fields of the Earth itself, and even chemical odors. It is thought that most birds probably use a combination of these cues and senses to find their way. Homing pigeons are probably the most recognized of avian navigators and are known to possess the incredible ability of somehow returning to their point of origin after being purposely displaced from a loft by as much as 800 km.

Generally speaking and with a few notable exceptions, such as vultures, birds do not have a very highly developed sense of smell and it has long been assumed that pigeons navigate by magnetic cues. However, creative experimental work published in 2001 by some Italian researchers discovered that pigeons rely on their sense of smell to detect volatile hydrocarbons for geographic orientation to at least some degree (Gagliardo et al. 2001). Recently completed research by Galiardo and colleagues, known as the Pisa experiments, has shown that pigeons rely on their sense of smell for navigation much more than was previously thought. This is exciting stuff because olfaction was always considered a secondary or even tertiary means of orientation in birds.

These researchers took 48 individual homing pigeons and surgically cut the nerves that relay information about smell to the brain in 24 birds and then severed what is known as the trigeminal nerve and is involved in the detection of magnetic fields in the other 24 birds. All of the birds were then transported 30 miles away from their loft and released. 23 of the birds that could no longer detect magnetic fields managed to find their way back to the loft within 24 hours, while only 4 of the birds that could no longer smell were able to navigate back to the loft and appeared to have lost all sense of direction with respect to their point of origin. These results suggest that smell is the key to how pigeons orient themselves and that they are actually able to perceive the landscape as some sort of odor map. This is an incredible discovery that forces us to reconsider what we thought we knew about avian navigation.

Birds in Binoculars are not the Birds In Books

February 23, 2011

Photo credit: BirdWatchingAdvice.com

The beginning birder experiences a lot of major challenges from the get go. Which binoculars to buy, what field guides are best, where to go looking for birds, how to find them, the list goes on and on. At first, the typical beginning birder is full of excitement about getting into a new hobby and looking forward to every new bird they might see. But often this enthusiasm turns into frustration and a sense of hopelessness as one begins to realize just how many bird species there are in world and how difficult it can be to simply identify any particular one. It can be an overwhelming emotion indeed.

Most new birders stop and take a deep breath, welcome the challenge and stand resolved to learn more and get better. Others drop off the road to serious birding enthusiast, decide that maybe hardcore bird watching is just not the inspiring cup of tea they seek and remain fine and dandy knowing and appreciating common birds. Whichever way the story goes, many a beginning bird watcher has an experience or two when a bird they see well or often, and maybe even get really good looks at, does not match up to the picture in their field guide.

It is a common expectation that the bird you see in your binoculars should match a bird you see in your books. The truth is that each bird you see is a unique individual and no single individual can be expected to match in every detail of the painting or photograph used in an identification guide. It would be like choosing the images of Elvis Presley and Marilyn Monroe to represent the typical male and female of all Homo sapiens in a field guide to primates. It is absolutely impossible to capture all of the known variation of any species of bird in a single image. Thus, the roles of a field guide is to present a fair representation of what might be considered a most typical individual and try to capture the average appearance of a species as an aid to accurate identification. In case of an artist’s representation of a species, the artist usually tries to paint a bird using a series of individuals for reference and merging the minutia of variation before them into a single image.

This is no easy task and there are almost always some individuals in a series with characteristics that fall well outside of the norm and must be left out of the final representation. Experienced birders sometimes refer to their overall impression of a species as gestalt or jizz, which is a play on G.I.S., or “general impression and shape”. This is akin to the feeling a birder gets about the identification of a particular individual of a species that is really similar to another species and hard to identify accurately in the field. This feeling, the gesalt, the jizz, is only something you can get from time in the field and concentrated consideration of tiny, but somehow noticeable variation. The sooner you realize that bird in your binoculars is different from the bird in your book, the closer you are to getting the jizz.

The Fanciful, Flightless Kiwi

February 21, 2011

photo credit: NatGEO website

In New Zealand’s fern-carpeted forests lives a very strange and reclusive creature. This nocturnal bird ventures out cautiously at night to probe for insects in the leaf litter. Its rounded body is covered in short, shaggy brown feathers, and its hunched posture makes it more reminiscent of a small, scurrying mammal than a bird. To round out its unique resume, this unique bird has inspired a namesake – an egg-shaped, furry brown fruit. Ladies and gentlemen…the Kiwi.

Physiologically, kiwis are incredibly unique. All five species of kiwi are members of the genus Apteryx, derived from the Greek word meaning “wingless.” While kiwis are not truly without wings, these bipedal birds have wings that are so disused they seem almost like an anatomical afterthought. Like other birds in its overarching group, called ratites, kiwis lack a keeled breastbone and the strong wing muscles that would be anchored to such a structure. These solid birds have so enthusiastically abandoned flight that their bones contain marrow, making them proportionally much heavier than their lighter, hollow-boned cousins. Kiwi feathers are downy and lack the barbules that give other birds their smooth appearance. As if to compound its devotion to its punk-rock plumage, these birds also lack preen glands with which to oil and organize their feathers.

Kiwis are physiologically adapted to feed and breed. The kiwi’s flexible bill curves downward to facilitate shuffling leaf litter, and their nostrils are positioned at the very tip, enabling the birds to sniff out buried insects with their strong sense of smell. With strong, heavy bones to support large eggs, the female kiwi is able to produce the avain world’s largest egg in proportion to her body. These chicken-sized birds produce an egg six times larger than an average chicken egg, weighing almost one-quarter of the weight of the female herself.

During the breeding season, male kiwis excavate underground burrows and prepare a nest area. His female partner must invest a large amount of energy in producing such an enormous egg. For a month after breeding, the female bird consumes up to three times her normal amount of food per day, ensuring that she has enough energy to survive the laying process. Several days before laying begins, the female stops eating – the egg has taken up so much space inside her that her stomach can no longer hold food. After the egg is laid, the male generally incubates for the required two to three months, perhaps because of the enormous amount of effort expended earlier by his mate. Males are devoted parents, leaving the nest so infrequently that their weight can decrease by one-third. Newly-hatched kiwis are covered in adult plumage, and survive in the nest for several days by slowly consuming the reserve yolk in its stomach. After it gains enough strength, the young bird accompanies its male parent on its first search for food.

Today, perhaps as a testament to their generally calm and hard-working demeanor, New Zealanders are called “Kiwis.” It seems that this shy bird just cannot escape notice – its distinctive characteristics have earned it the respect of a nation.

Rare birds: Area bird watchers have spotted some wild ones this winter

February 20, 2011

photo credit: media.bnd.com

There was something bizarre about the cardinal that visited Kay Campbell’s bird feeder during a February ice storm.

“He was so much brighter than the other cardinals,” she said. “Bright red with no black at all. He had a lighter beak. And pink feet.”

So the Swansea woman photographed it with a telephoto lens and brought it to Wild Birds Unlimited in Swansea.

Read more: here