Study reveals why timing of bird migration is changing

Nov 12, 2013
Credit: Tomas G Gunnarsson / University of Iceland

Researchers at the University of East Anglia have found out why birds are migrating earlier and earlier each year.

Experts have long suspected is somehow driving this advancing migration pattern. But new research published today reveals that individual birds migrate like clockwork – arriving at the same time each year.

However, is resulting in earlier nesting and hatching earlier each year, and this appears to be linked to the advancing migration.

Lead researcher Dr Jenny Gill from UEA's school of Biological Sciences said: "We have known that birds are migrating earlier and earlier each year – particularly those that migrate over shorter distances. But the reason why has puzzled bird experts for years. It's a particularly important question because the species which are not migrating earlier are declining in numbers."

The research team looked at a population of Icelandic black-tailed godwits over 20 years. During this time period, the flock advanced their spring arrival date by two weeks.

"The obvious answer would be that individual birds are simply migrating earlier each year. But our tracking of individual birds shows that this is not the case. In fact individual birds do almost exactly the same thing every year – arriving punctually at the same time year-on-year."

The team went on to investigate what could be causing the overall arrival time of godwits to creep forward.

"Because we have been following the same birds for so many years, we know the exact ages of many of them.

"We found that birds hatched in the late 1990s arrived in May, but those hatched in more recent years are tending to arrive in April. So the arrival dates are advancing because the new youngsters are migrating earlier.

"Climate change is likely to be driving this change because godwits nest earlier in warmer years, and that hatch earlier will have more time to gain the body condition needed for migration and to find good places to spend the winter, which can help them to return early to Iceland when they come back to breed."

This can also explain why advances in migration timing are not common among species migrating over long distances. "Many long-distance migrants arrive so late on the breeding grounds that they have little opportunity to respond to warming conditions by nesting earlier."

"This research is very important because many long-distance migrant bird populations are currently declining very rapidly, and identifying how climate change is affecting these populations is a key part of understanding the causes of these declines."

Explore further: Nature network hope for birds threatened by climate change

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On secondthoughtthinkagain
1 / 5 (6) Nov 12, 2013
Part of this study did surprise me. I would have assumed that birds would calculate the time to migrate based on the weather - early onset autumn or spring causing migration depending on the migration route.

Early onset spring makes birds decide to nest early so why not decide to migrate early as well.

If the bird is not calculating the season based on temperature or light levels then I wonder what method they are using.
NikFromNYC
1 / 5 (15) Nov 13, 2013
...as Wind Power World slices and dices rare birds...deck chairs are rearranged and a symphony plays as clitoris-chopping and harem-owning Barbarians pay both Al Gore and Phil "Hide The Decline" Jones to turn East "Climategate" Anglia University into a Saudi Arabian colony:
http://mpc.kau.ed...nes.aspx

The godwits are nesting earlier, don't you see, quite so, pip pip, as ne'er before.
NikFromNYC
1 / 5 (14) Nov 13, 2013
...and speeeeking of the Royal (Pain In The Ass) Society-supported East Anglians, Phil "Mike's Nature Trick" Jones, formerly on suicide watch via PR firm-tutored "poor Phil" politicking, the neaaaaarby OLDEST REAL THERMOMETER RECORD of Central England required "Hansen's Bulldog" blogger Grant Foster to FAKE a hockey stick out of, using the exact same Lying With Fucking Statistics strategy as East Anglian Jones relied upon to spoof the IPCC:
http://s6.postimg...cja1.jpg

Centraaaaal England is in good company too, regrettably for these biggest scientific scahhhhmers in huuuuman hissssstory:
http://postimg.or...v1zfzsd/

Scientific incest lies at the heart of East Anglian Climataaaah-logy, I do believe!
NikFromNYC
1 / 5 (14) Nov 13, 2013
"Researchers at the University of East Anglia...."

"For your eyes only...Don't leave stuff lying around on ftp sites - you never know who is trawling them. The two MMs have been after the CRU station data for years. If they ever hear there is a Freedom of Information Act now in the UK, I think I'll delete the file rather than send to anyone....Tom Wigley has sent me a worried email when he heard about it - thought people could ask him for his model code. He has retired officially from UEA so he can hide behind that." - Phil Jone$ of the University of EAST $AUDI ANGLIA ARABIA
NikFromNYC
1 / 5 (14) Nov 13, 2013
Nearby bird snuff video reenactment, by a Climatology Crucifix:
http://youtu.be/XJWILGGAUpw

Apologists for green boondoggle$ use little domestic cat kills as a smoke screen for grand bird Armageddon, shamefully, as perfectly natural bird adaptation to perfectly natural climate change is used to dehumanize and delegitimize the voices of reason in the modern (medieval?) world.
Maggnus
5 / 5 (4) Nov 13, 2013
Wow Nik, who the hell pays you? Your stupidity knows no bounds.
NikFromNYC
1 / 5 (12) Nov 13, 2013
Go tell Pollock jokes, poo-flinging Maggnus:

"Before what was one of the largest audiences to ever hear a speech denouncing UN global warming policies, Rothbard said he was honored to stand with the Poles in a "new battle for freedom against those who would use environmental and climate alarmism to steal away our liberties and give international bureaucrats control over our energy sources, our daily lives, our prosperity, and our national sovereignty."

Date: 11 November 2013
Speaker: A Skeptic!
Audience size: 50,000
Event: Polish National Independence Day Rally

Five minute video of English translator accompanied speech against climate alarm:
https://www.youtu...BTTg#t=0

See, Maggnus, those "stupid" Poles have already faced down fascism, so now it's old hat, thanks to Climategate. James Delingpole's book called you guys "watermelons" since you're really just Red on the inside with a Green facade:
http://www.amazon...-Colors/
NikFromNYC
1 / 5 (12) Nov 13, 2013
P.S. I pay myself, slanderous myth maker, which is why I'm free to speak out, unlike the academics you activists terrorize. Would any conservative think tank pay me to post my middle finger on a porn banner site?

http://s6.postimg...mage.jpg

If you got *that* wrong, what the fuck do you expect anybody to believe you have *right*?!

At least you're in good fat company with Michael "Hide The Decline" Mann, about my posts trying to clean up Phys.org, who claimed my handiwork here "Smelled like Koch":
http://wattsupwit...nomenon/
NikFromNYC
1 / 5 (12) Nov 13, 2013
Sorry Maggnus The Mental Masturbator, I left out the banners by using a direct JPG link.

So what exactly is it that you find "stupid" about my use of sample trigonometric function input data fed through the Savitzky–Golay filter to demonstrate end effect artifacts related to the alarmist work of not one but two Climategate e-mailers?

Did I not properly center my principle component weighting, like Michael Mann did in his hockey stick, that if corrected *falsifies* his radical historical deletion of the established Medieval Warm Period?
NikFromNYC
1 / 5 (12) Nov 13, 2013
Hey Maggnus, I notice in the Activity tab for user profiles here that you downrated my comments ALONG WITH MULTIPLE FAKE ACCOUNT RATINGS BOTS that include Al_Gore and Michael_Moore, but that no such ratings bots devoid of verbal activity appear on the skeptical side. Don't you find it disturbing that such suspicious and, well, quite stupid tactics attach to you here? It's kind of self-defeating don't you think? Or do you think it's a smart idea to publicly display dishonesty? And don't you worry that the five stars I gave you will *alert* ratings filter users to drama worthy hidden content in a way that will pique their interest? Not very smart of you, that!