Birds

[Mountain Crown]

Thanks for these treesparrow.

Owls are wonderful creatures.

 

[truth seeker]

Thanks for these treesparrow.

Owls are wonderful creatures.

Ditto. Thanks for the pics, treesparrow.

 

[Voyageur]

Thanks for these treesparrow.

Owls are wonderful creatures.

Ditto. Thanks for the pics, treesparrow.

Ditto also, great photo's and amazing abilities of camouflage you've presented. With some synchronicity to this, being in the right place last night, was delighted with the sounds (singular owl) echoing in the dark.

 

[treesparrow]

Homing pigeons navigate by sound

Posted on: 12 Feb 2013

Pigeons are known to use several methods to navigate, but perhaps the least known is sound – new research has found it to be more important than was thought.

Homing pigeons are well-known to be great navigators, returning to their home lofts using landmarks, orientation by the sun, the earth's magnetic field and also the spatial distribution of atmospheric odours. However, it seems that sound waves may play a hitherto unsuspected role in this mysterious ability.

Using an 'acoustic ray tracing program', scientists from Cornell University, New York (NY), USA, were able to trace sound waves generated by movements deep in the oceans and affected by different densities in the earth's crust, and found that they are key to pigeons' abilities to find their home loft.

This possibility was first highlighted when Jon Hagstrum of the US Geological Survey read about pigeons occasionally losing their way home in certain localities in the USA. He was reminded of a lecture he had attended by Professor William Keeton at Cornell, who described pigeons consistently taking the 'wrong turn' on their way back to a release site at Weedsport, NY. Other birds released at nearby Jersey Hill, NY, also tended to head off in random directions.

Having kept data from between 1968 and 1987, it was noted that on 13 August 1969 in particular, these same birds had taken the correct bearing. There had to be a connection– having ruled out a disturbance in the earth's magnetic field, Keeton wanted to know if the cause could be geological.

Further casual reading came up with the fact that pigeons can hear infrasound – sound waves lower than the human ear can register. Infrasound is generated regularly by the movements in ocean waters, as well as randomly by seismic waves, and such sounds can be transmitted through the earth and water for thousands of miles - Grey Whales in the Pacific Ocean use sounds of a similar frequency to communicate through hundreds of miles of seawater.

Putting the two pieces of information together, Hagstrom wondered whether homing pigeons listened for the unique infrasound 'rumble' of their home area to locate their loft. clearly, if this rumble was disrupted or shielded from the birds, they would get lost.

Hagstrum had to reconstruct atmospheric conditions on each day that the pigeons were released, particularly when they got lost, with a complex acoustics algorithm, and climatic, wind direction and wind speed data from those days was gathered from the records of local weather stations. The probable journey of the infrasound through the atmosphere was then calculated and modelled. It turned out that on the days when the birds got disoriented, local ultrasound had been deflected away from the ground and sent high into the atmosphere, having been refracted by the different densities of air layers. On all of the days when the pigeons had disappeared from Jersey Hill, the loft's infrasonic signal was being sent away from where the birds were able to pick it up.

But why had the birds repeatedly taken the wrong bearing? It seemed that the contours of the land and the winds had carried the infrasound to where it approached the loft from a different direction, leading the birds to take the wrong bearing.

Using Keeting's own data, Hagstrom was able to answer his question 36 years after his lecture. Pigeons get their bearings from the loft's infrasonic signature before setting their internal compass, which is guided by the sun. Locally they use the sound waves, while on a larger scale they use the more well-known techniques.

This also offers an intriguing tit-bit for those birders trying to explain vagrancy. Migratory wild birds are also likely to use such aural information in setting their own directional bearings. If the weather interrupts the sound waves from their own natal or wintering areas, they could easily get lost and sometimes end up even on the wrong continent.

Reference
Hagstrum, J T. 2013. Atmospheric propagation modeling indicates homing pigeons use loft-specific infrasonic 'map' cues. The Journal of Experimental Biology DOI: 10.1242/%u200Bjeb.072934.

_http://www.birdwatch.co.uk/channel/newsitem.asp?c=11&cate=__13485

 

[treesparrow]

Vulture invasion strikes New Jersey suburb: ‘It’s like Alfred Hitchcock’

The scavengers have settled by the 100s in the Martinsville section of Bridgewater, N.J., about 30 miles west of Newark.
By Adam Edelman / NEW YORK DAILY NEWS

Talk about a fowl encounter.

In what seems like a scene out of Alfred Hitchcock’s “The Birds,” more than 100 vultures have invaded an upscale New Jersey suburb, taking up residence in backyards, trees and on roofs.

Residents of the Martinsville section of Bridgewater, N.J., about 30 miles west of Newark, have grown spooked by the infestation and are considering some unconventional methods in trying to shoo away the ugly birds.

"I noticed them about two years ago and thought, now that's a big bird," Tim Friar, a resident of the neighborhood, told NJ.com.

"Then I started to see an ungodly amount. It's just eerie,” added Friar, who said he’s counted at least 130 vultures on his roof alone.

Vultures are large and sharp-beaked, but generally harmless, birds that are known to scavenge the carcasses of dead animals. And they aren’t entirely foreign to New Jersey. Vultures have been spotted in the fall before in some areas, roosting in trees overnight. But they’ve never been seen in such great numbers.

Another resident, Patti Beitz, said the birds can, at times, be fairly aggressive.

At night, she’s seen the birds gather overhead in large clusters of up to 40 and begin to circle and swoop.

"I've seen them drop pieces of bone and things from the air. They're not nice birds," Beitz said.

Friar, Beitz and other neighbors said they noticed that the vultures arrived in large numbers not too long after Hurricane Sandy.

But the strange animals aren’t just a nuisance — they can cause damage.

Vultures in the U.S. have been known to peck holes in roofs, eat window insulation and even attack people or animals, on occasion.

So residents, growingly increasingly anxious about the situation, contacted wildlife authorities last week to try to get rid of the birds.

Nicole Rein, a wildlife biologist at the U.S. Department of Agriculture Wildlife Services office, was assigned to the problem.

The solution, she said, is to hang dead vulture carcasses — upside-down with wings spread — in areas around town that are worst affected.

Rein said she’s headed to the area Monday to hang the dead birds, before the problem, which has been growing worse, gets even more out of hand.

“All we hear are feathers when we’re outside,” said resident Jessica Guarino. “It’s like Alfred Hitchcock.”

Video report -
http://www.nydailynews.com/news/national/n-suburb-overrun-vultures-article-1.1283477

 

[treesparrow]

Bird brains can crack nut trading game with self-control: study

OSLO (Reuters) - Cockatoos can delay eating nuts in order to win tastier ones, a surprise sign that birds can exercise self-control, a trait usually seen as the preserve of animals with larger brains, a study showed on Wednesday.

Scientists gave Goffin cockatoos, a mainly white species from Indonesia, a nut while showing them a more attractive one just out of reach. If the birds did not nibble the first nut for up to 80 seconds, they learnt they would get the second instead.

"Imagine placing a cookie directly into a toddler's mouth and telling him/her that he/she will only receive a piece of chocolate if the cookie is not nibbled for over a minute," said lead author Alice Auersperg at the University of Vienna.

"Only few, typically large-brained animals have been shown to be able to inhibit the consumption of an immediate food reward in anticipation of a bigger one for more than one minute," the University said in a statement.

The birds were given pecan nuts, and all 14 of those studied waited for up to 80 seconds to win a more attractive cashew nut, according to the findings in the journal Biology Letters.

A video showed one bird, Muppet, waiting 40 seconds while strutting agitatedly around a table top with the first nut in its beak before exchanging it for a second.

(http://youtu.be/c86EYtmllhc)

Self-control in human infants was studied in the 1970s in the Stanford Marshmallow Experiment. Under that test, children were given a marshmallow and told that they would get a second if they did not eat the first for several minutes.

Commenting on that test, the Vienna University statement said. "Interestingly, children who were able to wait for the delayed reward showed greater success in adult life than the ones who ate the first marshmallow right away."

The ability to trade depends on being able to suppress the impulse to eat the first reward. It also requires a judgment on the reliability of the trader and the relative costs of the delayed reward, Vienna University said.

(Reporting by Alister Doyle, Environment Correspondent; Editing by Louise Ireland)

_http://news.yahoo.com/bird-brains-crack-nut-trading-game-self-control-104953295.html

 

[Voyageur]

From ARKive: Seen here are two Bald Eagles in their courtship flight, involving touch and spinning. To me this seemed just so marvelous as a brief glimpse into their world; like poetry on wings - hope you enjoy. :)

The bald eagle is monogamous, and thought to pair for life, reinforcing the pair bond through spectacular, acrobatic flight displays that include the pair flying to a great height, locking the talons, and cartwheeling towards the ground, only breaking off at the last moment.

http://www.arkive.org/bald-eagle/haliaeetus-leucocephalus/video-09d.html#utm_source=social-network&utm_medium=share&utm_campaign=species-bald-eagle

 

[Palinurus]

Hi voyageur,

The video you posted could easily have been to the point here as well:

http://cassiopaea.org/forum/index.php/topic,31348.0.html

 

[Voyageur]

Hi voyageur,

The video you posted could easily have been to the point here as well:

http://cassiopaea.org/forum/index.php/topic,31348.0.html

Yes, tragic result for those adult birds. It speaks of territorial issues in that case. It might however happen also to the juveniles during their courtships.

 

[Voyageur]

This years hummingbirds arrived early and generally they have been in lesser numbers. In the last week the population at home has gone from 8 to close to 20 (very hard to count). They have been draining the water in this feeder within 2 days and usually it is 6-7 days. So today while filling up the feeder, just in the very in the act of hanging it back up they started flying back in as a swarm. They were landing on my head and arms; flying in a general frenzy. This shot was taken not much more than it appears (< 2 ft.) on macro and it only captures a small portion of how many there were.

In all the years feeding them through the summer, have never once seen them behave like this.

 

[Rich]

That's a fantastic shot of the action. Thanks for sharing.

 

[anart]

Hmmm, the very late spring must be seriously affecting their usual food sources. You may, in fact, be saving their lives with the feeder. Maybe you should put another couple of them up?

This years hummingbirds arrived early and generally they have been in lesser numbers. In the last week the population at home has gone from 8 to close to 20 (very hard to count). They have been draining the water in this feeder within 2 days and usually it is 6-7 days. So today while filling up the feeder, just in the very in the act of hanging it back up they started flying back in as a swarm. They were landing on my head and arms; flying in a general frenzy. This shot was taken not much more than it appears (< 2 ft.) on macro and it only captures a small portion of how many there were.

In all the years feeding them through the summer, have never once seen them behave like this.

 

[Voyageur]

Hmmm, the very late spring must be seriously affecting their usual food sources. You may, in fact, be saving their lives with the feeder. Maybe you should put another couple of them up?

This is one of four and for reasons unclear (am thinking it may be the heat from the SW), this one is focused on the most, although they do attend to the others.

 

[Voyageur]

I had no idea just how complex and incredibly suited their tongue's are for capturing nectar - as a function (in the animation seen here) of biological design, it is truly remarkable.

The Genius of Birds: Watch a Hummingbird's Tongue in Action
David Klinghoffer June 18, 2013

We recently got a hummingbird feeder for our back porch and my kids were delighted to see how quickly the local hummingbird population discovered it. I tried to explain to them what's so amazing about the creature's tongue. Watch this clip from the new Illustra documentary Flight: The Genius of Birds. Paul Nelson's commentary is also very eloquent and appropriate.

_http://www.evolutionnews.org/2013/06/the_genius_of_b073491.html

 

[Nienna]

I had no idea just how complex and incredibly suited their tongue's are for capturing nectar - as a function (in the animation seen here) of biological design, it is truly remarkable.

The Genius of Birds: Watch a Hummingbird's Tongue in Action
David Klinghoffer June 18, 2013

We recently got a hummingbird feeder for our back porch and my kids were delighted to see how quickly the local hummingbird population discovered it. I tried to explain to them what's so amazing about the creature's tongue. Watch this clip from the new Illustra documentary Flight: The Genius of Birds. Paul Nelson's commentary is also very eloquent and appropriate.

_http://www.evolutionnews.org/2013/06/the_genius_of_b073491.html

That was, to me, fascinating.