Via Eurekalert
Smithsonian scientists find declining rainfall is a major influence for migrating birds
Instinct and the annual increase of daylight hours have long been thought to be the triggers for birds to begin their spring migration. Scientists at the Smithsonian Conservation Biology Institute, however, have found that that may not be the case. Researchers have focused on how warming trends in temperate breeding areas disrupt the sensitive ecology of migratory birds. This new research shows that changes in rainfall on the tropical wintering grounds could be equally disruptive. The team’s findings are published in scientific journal Proceedings of the Royal Society B, March 30.
Many of the bird species that breed in the temperate forests, marshes and backyards of North America spend the winter months in the tropics of the Caribbean, and Central and South America. Insects are the primary food for many birds during the winter, and rainfall largely determines the amount of insects available. Climactic warming, however, is causing declining and more variable rainfall cycles in many areas, affecting the availability of insects and delaying when birds leave for their northern breeding grounds. To examine this, the Smithsonian scientists focused on American redstarts (Setophaga ruticilla), a member of the warbler family, at a non-breeding site in Jamaica where they conduct long-term studies.
“American redstarts were a perfect species for this study since they defend exclusive territories throughout the non-breeding period until they depart for spring migration and most return back to the same territory the following year,” said Pete Marra, research ecologist at the Smithsonian Conservation Biology Institute’s Migratory Bird Center. “These behaviors made it relatively easy to keep track of individual birds over multiple years and document changing spring departures. Each individual was fitted with a unique combination of colored leg bands.”
Precipitation in Jamaica is highly seasonal, with consistent rainfall from September to November and a pronounced dry season from January to March. The scientists observed the redstarts in their non-breeding territories for five years during the dry season. They paid special attention to the annual variation in dry season rainfall. The correlation between the amount of insects in a bird’s territory and the timing of its departure suggested to the team that annual variation in food availability was an important determining factor in the timing of spring migration. Had the redstarts relied on internal cues alone to schedule their spring departure, they would have all left their winter territories at the same time each year.
“Our results support the idea that environmental conditions on tropical non-breeding areas can influence the departure time for spring migration,” said Colin Studds, a postdoctoral fellow at the Smithsonian Conservation Biology Institute’s Migratory Bird Center and lead author of the study. “We found that the same birds changed their spring departure from one year to the next in relation to the amount of rainfall and food in March.”
During the past 16 years, the dry season in Jamaica has become both increasingly severe and unpredictable, leading to an 11 percent drop in total rainfall during the three-month annual drought. Making the future even more dire, climate models predict not only increased warming on temperate breeding areas but also continued drying in the Caribbean.
A critical question for the scientists is whether this variation in the onset of spring migration carries consequences for the birds. Delaying departure could be beneficial if food resources are low and the individual has not yet stored enough energy to migrate. However, delaying departure could affect arrival time to its breeding territory and result in less time to successfully reproduce. “Because American redstarts return to the same site to breed each year, arriving later may make it harder for them remain to remain in synch with their breeding cycle,” Studds said.
And this just in. Seems small birds are quite adaptable to climate/weather change. Besides, couldn’t resist the headline. 😉
http://www.thesun.co.uk/sol/homepage/news/3500812/Tits-are-bouncing-back-in-British-gardens-a-survey-reveals.html?OTC-RSS&ATTR=News
I’m sure the decade long drought of the dust bowl years….
…didn’t bother them one bit
LOL!
“Making the future even more dire, climate models predict not only increased warming on temperate breeding areas but also continued drying in the Caribbean.”
I never read the entire press releases but just make my browser search for “climate”. Saves time. I’m optimistic for the birds – after all, climate models have been wrong every time up to now.
Food for thought?
http://pielkeclimatesci.wordpress.com/2009/08/05/comment-on-%E2%80%9Crecent-changes-in-climate-extremes-in-the-caribbean-region-by-peterson-et-al-2002%E2%80%9D-by-rj-stone/
Migrating birds have a lot more to worry about than a bit of warmth and dry weather. That’s the least of their problems. I’m wondering how the Japanese Snipe that visit my place in Australia in our summer and breed in the Honshu marshes got on with the tsunami. Then they have to cope with the huge Chinese and Korean coastal land reclamations, typhoons etc. We do need, though, to be aware of their problems and leave them a bit of space.
Dire. Climate Models predict.
It is dire indeed when the darn Climate Models can’t get a season correctly predicted, and whole cities and counties are caught flatfooted by erroneous forecasts.
If I were a bird, I’d worry more about cats:
http://news.nationalgeographic.com/news/2004/09/0907_040907_feralcats.html
Stephen Rasey says:
April 1, 2011 at 1:05 pm
“Maybe these ecologists issuing alarms are really Creationists at heart. Perhaps they think the World was created 6000 years ago just as it was in 1940 before we humans commited original sin through postwar industrializaiton. It would explain a lot.”
Now, that is worth some thought. I know they are steady-staters. They believe that Earth was pristine and unchanging until 1850 when Karl Marx first noticed a decline in the human condition. They are struggling to stop the decline before it becomes a runaway freight train and civilization returns to its pre-1850 state. Ironically, their method of stopping the decline is to so encumber human initiative that civilization will return to its pre-185o state.
“Instinct and the annual increase of daylight hours have long been thought to be the triggers for birds to begin their spring migration.”
The most famous migrant birds are swallows that migrate at the END OF SUMMER. The most famous example are swallows that migrate from the city og Goya, Corrientes province, I Argentina and fly for about 30 days to San Juan Capistrano abbey in Capistrano, California.
They travel from many cities in Argentina to Goya, and on February 19th, they depart towards California, arriving there on March 29th, sharp. There is a famous festival in Capistrano greeting the arrival of the swallows. They return to Goya and other cities in Argentina on October 23rd, every year –sharp.
The problem is that swallows have been departing from Goya one two and three days earlier than before. Warmists say that’s a signal that spring is arriving early –but swallows have no internet connection or Watch TV to check how the climate is in California. They simply feel that temperatures are falling more than usual (as has been happing in Argentina) and say “let’s blast off, before it gets too cold here!”
In http://www.arkanimals.com/capistrano-swallows/ there are the followings quotes:
“The amazing journey takes the swallows over 12,000 miles round-trip. They abandon their winter haven in Goya, Corrientes, Argentina and travel to southern California, arriving on St Joseph’s Day (March 19th) and then begin the return trip to Argentina on the Day of San Juan (October 23rd).”
“Just why the swallows’ migration has changed is up for speculation.
Locals and visitors alike have celebrated the annual migration of the swallows for as long as some of us can remember, and it is disappointing to those who show up for the Swallows Day Parade only to find the avian ambassadors missing.
So the Smithsonian Conservation Biology Institute should come down to Argentina and check for a variation to their hypothesis.
Algebra says:
Climactic warming?
——————-
Yes, its the latest name for Global Warming. I noticed this new branding in todays “The Vancouver Sun” where the term used was Climate Warming, in an article about “How all the fish are gonna die from the hot river water” or something like that.
http://www.vancouversun.com/technology/Salmon+survival+depends+spawning+spot/4541136/story.html
Since we have up to 6 pairs of redstarts breeding on our land every year, and I’m a birder, this is interesting… but stupid.
What they are basically saying is that migrating birds respond to the real world. Any birder knows this. But they don’t seem to realize that this screws up their AGW apocalypse story about all the birds migrating like clockwork and dying off because spring hadn’t arrived, etc.
Also, this story implies that there is some tightly limited window when these (or any) birds can successfully breed. But their arrivals and departures vary annually and some bird nest later than others. Moreover, look at the huge breeding distribution of the redstart and you can see how flexible they are overall.
So, more desperate and stupid efforts to link the climate to something.
But very nice photo.
Such a cute little feller pictured in the photo.
His family lineage having evolved over 1000s and 1000s of years and the ability to fly for long distances, probably prepares him just fine for drought and other inconveniences.
Hey Smithsonian! Don’t insult his intelligence.
He can adapt to a changing climate….whatever nature brings him.
Unfortunately, it seems, homo sapiens can’t.
Too stupid.
They are too busy barking up the wrong tree chasing after the CO2 molecule while rest of the biosphere passes them them by, evolving as they go [including generations of adaptable redstarts].
How Science in all its august splendor, which has brought us so much knowledge, understanding, technology, and advancement, has DEVOLVED into this CIRCULAR reasoning game “peer reviewed research” using catch-phrases such as “climate models predict and “a warming world” etc. etc, ad nauseum…is BEYOND ME!
Shameful.
I’ll bet if that little handsome bird in the picture could laugh…he would be laughing at US!
Chris
Norfolk, VA, USA
“If I were a bird, I’d worry more about cats:”
CRS, Dr.P.H.
Yes indeed! and even some so called solutions to AGW:
http://co2insanity.com/2011/03/31/wind-turbines-killing-bats/
Getting near the end of a lifetime’s work as a Civil Engineer, I see that here we have a bunch of guys and gals being paid by the kind US taxpayer to spend their days spotting birds in Jamaica.
No doubt they have a nice inflation proof pension to look forward to. No doubt they also get to fly around to a few nice all-expenses-paid “conferences” in exotic locations to break the monotony.
Only snag is that they have to produce a few doom-laden prognoses with citations of climate modelling papers. But no doubt they have computer software that produces the bare bones of this, just at the click of a mouse.
Meanwhile, the little tweetie-pies keep on happily doing their own thing, seemingly without a care in the world (apart from the feral cats).
I have to scratch my head and wonder, why weren’t there careers like that available when I was a bright young graduate?
ferd berple says:
Notice that Jamaica says the dry periods are getting wetter, while the Smithsonian says the dry periods are getting dryer.
Wonder what the Meteorological Service of Jamaica has to say about the weather around the Smithsonian 🙂
sorry, I dont believe this. Birds start their migration to time their arrival for when their target insects emerge as well as temperatures. RAIN OCCURS RANDOMLY.
Since all of these “scientists” seem bound and determined to deprive green plants, to the greatest extent possible, of the always scarce (less than 40 molecules per 100,000 molecules) carbon dioxide that is absolutely required for the growth of plants that produce the food birds eat, I tune out.
The future can not be predicted by extrapolating the recent past into the future. ASSUME makes an ASS out of U and ME every time, if we go along with unfounded speculations, oftentimes nowadays called “theory”.
We had something along these lines last year in the UK ,the scare story was small birds were rapidly declining in numbers.
However when the RSPB did a survey this year they discovered the populations of small birds were actually thriving.
In fact this article I hate to say is from the Guardian,yuk.
Just scaremongering ,again.
http://www.guardian.co.uk/environment/2011/mar/31/big-garden-birdwatch-breading-success
It sure was lucky that the Beagle happened to land in the only island group on the face of the earth that has variable local conditions, or else Darwin might never have noticed that species are capable of adaptation to geography and climate. [/sarc]
The sad thing is, too many people think that “conservation = environmental stasis”. Any change at all from what they decide are ideal conditions is a Bad Thing, even if it’s 100% natural.
if they(enviros) cared about birds they’d be worried about (human)population increase and the inevitable resultant habitat destruction….here in the U.S. the population increase is driven entirely by illegal immigration, so when the enviros dare to speak about curbing/stopping illegal immigration i’ll be happy to take them seriously again, until then “yawn”…
and these kind of studies with “global warming is going to cause this and that and the other” just go in one ear and the other now because i just can’t help but picture these “scientists” getting a pat on the head and a few quarters from uncle Algore for putting out this claptrap…
I though the windfarms will be killing them. Strange for Al Gore, his Silent Spring might come after all, via windfarm, even night will be dead for ultrasound as all the bats will be dead. The whales are also getting beached from the ocean wind farms.
BAN THEM SAVE THE BIRDS!!!
The assumption that the climate is always hotter and dryer does not reflect the reality of the last few years. I would encourage the author to study changes in patterns related to cold and wet also.
Reports on unexpected changes to migration patterns for bees, animals and birds have been reported for the last decade+. Climate could impact migration patterns but changes in the earth’s shifting magnetic fields would certainly drive them.
Are there sudden changes to fields due to magnetic burps from the earth that cause birds to fall in mass from the sky? Is the current magnetic shifting pole interfering with an animal’s ability to navigate to the correct seasonal target location or causing the animal to choose a new, more suitable location?
The bird migrated. Jamaica? No it flew of it’s own accord.
As for changes in rainfall in last sixteen years, ENSO anybody?
Maybe I’m being sarcastic.
It has been determined that scientists banding and studying birds alters the birds habits.