Aves (birds)
gregladen | April 18, 2009Or, more exactly, where are they all going to go during the next two or three months?
I'm sitting here between a large frozen lake and a small "pond" (connected to the lake with a channel) that has patches of open water on it. (The melting on the pond is probably because the bioactivity at the bottom of the pond increases water temperature.) There is a pair of mallards on the pond, and I expect that in a few weeks there will be two or three mallards and three or for mergansers, all females, and each with between six and 12 or so ducklings. These 60 ducklings will initially hang out only…
gregladen | March 31, 2009Scientists have reported a strange twist in the tale of Europe's harbinger of spring the Common Cuckoo Cuculus canorus. In a dramatic discovery, returning cuckoos have been heard and filmed calling with a highly distinctive variation of the normal call. The new call is best described as "Ooo-Cuck, Ooo-Cuck".
Bird Life International
gregladen | March 25, 2009As you know if you read my blog, Trivers Willard is an important theoretical construct which has been tested numerous times. TW works in some species, not in others, and overall, that should be predictable (accroding to TW).
It turns out that finches control the sex of their offspring, and do so in a way that TW would predict, apparently. There is a paper in Science that I'll probably eventually get to writing up for you, and in the mean time, here's a quick news report from Scientific American.
See if you can figure out how Trivers Willard is working here, and why the important…
gregladen | March 21, 2009You've heard about the dismal report of the state of birds in the US. Here is a detailed account of the USFW et al report.
And here are a few different items regarding migratory birds and what you can do about them.
Citizen Science Is for the Birds
Open Data: Help Migratory Bird Observations Fly into the Digital Age
Help Science: Build Your Own Bird Tracker, Cheap
New project aims to digitise hand-written migration records...
gregladen | March 16, 2009A California Condor was apparently ill (with suspected lead poisoning) so it was brought in for treatment. It was then discovered that it had been shot some time earlier .
Unable to eat on its own, the condor was under intensive care at the Los Angeles Zoo and its prognosis was guarded, said Susie Kasielke, curator of birds.
X-rays taken at the zoo turned up shotgun pellets embedded in its flesh, she said. Those wounds had healed.
It could not be determined if the pellets were lead or steel, but the poisoning was most likely caused by the bird ingesting spent lead ammunition in carcasses of…
gregladen | March 14, 2009This is the river just above the dam (you can click this picture for a whopping big version):
And these birds seem to be waiting for the other shoe to drop:
gregladen | February 15, 2009This is interesting, from a National Geographic press release:
TORONTO, Feb. 12, 2009 - A York University researcher has tracked the migration of songbirds by outfitting them with tiny geolocator backpacks - a world first - revealing that scientists have underestimated their flight performance dramatically.
"Never before has anyone been able to track songbirds for their entire migratory trip," said study author Bridget Stutchbury, a professor of biology in York's Faculty of Science & Engineering. "We're excited to achieve this scientific first." Songbirds, the most common type of bird in…
gregladen | January 2, 2009Scientists monitoring at Mount Moreland - South Africa's largest Barn Swallow Hirundo rustica roost - have captured their first overseas ringed bird from a festively snowy location. The young Barn Swallow had flown all the way from Finland - a total of 11,000 km! "This is an amazing Christmas gift", said Hilary Vickers of the Lake Victoria Conservancy - sponsors of the Mount Moreland ringing programme.
"We were carefully fitting the swallows with rings so we can monitor their movements when we spotted a bird already carrying one", said Mount Moreland bird-ringer Andrew Pickles. "A magnifying…
gregladen | December 17, 2008Predatory rodents are eating the chicks of the Critically Endangered Tristan Albatross Diomedea dabbenena to the extent that they have had the worst breeding season recorded so far.
The mice are also affecting Gough Island's other Critically Endangered endemic species, Gough Bunting Rowettia goughensis. A recent survey of the bunting's population revealed that the population has halved within the last two decades. Now there are only an estimated 400-500 pairs left.
"We've known for a long time that the mice were killing albatross chicks in huge numbers. However, we now know that the…
gregladen | December 5, 2008The RSPB (BirdLife in the UK) and other partners have launched a last push to find one of the world's rarest birds.
They have issued a call to search for and find any remaining populations of Slender-billed Curlew Numenius tenuirostris. This announcement was made at the Ninth Meeting of the Conference of the Parties to the Convention on Migratory Species (UNEP-CMS COP 9), in Rome, Italy, 1-5 December.
Classified as Critically Endangered, Slender-billed Curlew is the rarest species found in Europe, the Middle East and North Africa, with no confirmed records since 1999
More here.
gregladen | December 2, 2008Analysis of this year's seabird breeding data on RSPB (BirdLife in the UK) coastal reserves shows that Black-legged Kittiwake Rissa tridactyla, Arctic Tern Sterna paradisaea and Parasitic Jaeger Stercorarius parasiticus - more commonly known as Arctic Skua - have had a terrible season, with virtually no chicks reared to fledging in the far north of the UK. Changes in food supply, which may be linked to climate change, could threaten the future of these species in the UK.
more
gregladen | December 1, 2008
Cool. Is it or isn't it? Hey ... the UPS guy... he saw it!
Learn more here.
gregladen | October 26, 2008The lake is icy-green and in the distance almost blends into the sky through a fast moving fog bank. The bald eagles (a pair and one offspring) are up to something in the back, one of them making swings over the bay and then back into the yard where they are vocalizing quite a bit. The pair of loons that always nests on the point a few hundred meters across the bay have changed to their winter plumage and are actively feeding just outside the cabin, and have been for two days. This year, they did not successfully raise an offspring, which is unusual. so we didn't get to see the cute baby…
gregladen | October 19, 2008Plant and animal fossils recently discovered from an island in the Bahamas tell a story of habitat change and human involvement in local extinction.
These finds are reported in a paper by Steadman et al. in the Proceedings of the National Academy of Sciences.
Most people with an interest in natural history know about one or more regions that were at one time covered by "a great inland sea." For instance, if you live in the American Midwest, you probably know that much of this region was covered by such a sea, evidenced by extensive limestone beds and other geological manifestations. As…
gregladen | September 29, 2008Fossils of a newly discovered species of dinosaur -- a 10-meter-long, elephant-weight predator -- were discovered in 1996 along the banks of Argentina's Rio Colorado, and are now being reported after a long period of careful study. This dinosaur dates to about 85 million years (which falls within the Cretaceous period).
Perhaps the most interesting feature of Aerosteon riocoloradensis is that it demonstrates the evolution of a bird-like respiratory system in an animal that is definitely not bird-like in most other ways. Indeed, the authors of this paper imply that this dinosaur's…
gregladen | August 20, 2008A typical adult human recognizes that the image one sees in a mirror is oneself. We do not know how much training a mirror-naive adult requires to do this, but we think very little.
When a typical adult macaque (a species of monkey) looks in the mirror, it sees another monkey. Typical adult male macaques stuck in a cage with a mirror will treat the image as a fellow adult male macaque until you take the mirror out of the cage.
(Experiments that attempt to determine if an individual can recognize themselves in the mirror ultimately derive from what is known as the Gallup Test, after Gordon…
gregladen | August 18, 2008The Shy Albatross
A study of trawl fishing in South Africa suggests that around 18,000 seabirds may be killed annually in this fishery, highlighting trawl fisheries as a major threat to seabirds, especially several species of albatross already facing a risk of extinction.
Published in the journal Animal Conservation, the study was based on scientists monitoring catches on 14 different vessels, operating in the Benguela Current, off South Africa; one of the main hotspots for seabirds in the Southern Hemisphere. The vessels were trawling for hake, and the majority of bird deaths were a result…
gregladen | August 3, 2008 New Smithsonian Field Guide Smithsonian Field Guide to the Birds of North America by Ted Floyd is a newcomer to the bird field guide scene. This guide offers a new combination of features that may make it the best choice as the primary guide for a small number of birders, and as an excellent second (or third) guide for most birdwatchers. Given the guide's qualities and price (it is not expensive) if you are a North American birder (anywhere in the region) this is a must-have for your collection, and if you know a birder who is having a present-able event (birthday, etc.) any time in the…