Two years ago, it was “Study says global warming shrinks birds” now thanks to impressive further study, they’ve discovered it’s “Bigger birds in central California, courtesy of global climate change.“
Can’t they get their story straight? Why don’t they ask Jim Henson Hansen?
From San Francisco State University
Bigger birds in central California, courtesy of global climate change
SAN FRANCISCO — Birds are getting bigger in central California, and that was a big surprise for Rae Goodman and her colleagues.
Goodman uncovered the trend while working as a graduate student for San Francisco State University biologist Gretchen LeBuhn, analyzing data from thousands of birds caught and released each year at two sites near San Francisco Bay and the Point Reyes National Seashore.
The SF State scientists, working with researchers from PRBO Conservation Science and the San Francisco Bay Bird Observatory who collected the data, found that birds’ wings have grown longer and birds are increasing in mass over the last 27 to 40 years.
What’s making the birds bigger? The researchers think that the trend is due to climate change, but their findings put a twist in the usual thinking about climate change and body size. A well-known ecological rule, called Bergmann’s Rule, states that animals tend to be larger at higher latitudes. One reason for this rule might be that larger animals conserve body heat better, allowing them to thrive in the generally colder climate of higher latitudes.
Under this reasoning, some scientists have predicted that animals would get smaller as the Earth has warmed up over the past 100 years. But the study, published in the journal Global Change Biology, suggests that the connection may not be so simple.
Climate change may affect body size in a variety of ways, they note in their paper. For instance, birds might get bigger as they store more fat to ride out severe weather events, which are expected to be more common under global climate change. Climate change could also alter a region’s plant growth, which may eventually lead to changes in a bird’s diet that affect its size.
LeBuhn, an assistant professor of biology, said she was “completely surprised” to find that the central California birds were growing larger over time. “It’s one of those moments where you ask, ‘what’s happening here?'” The results were so unexpected, she said, that the findings made them take a step back and look more closely at how climate change could influence body size.
The bird data come from two long-term “banding stations” in central California, where a wide variety of birds are captured, banded about the leg with an identification tag, and weighed and measured before being released. Many of the same birds were captured each year, allowing the researchers at the sites to build up a unique database that could be used to track changes among the birds over several decades.
The researchers used data from 14,735 individual birds collected from 1971 to 2010 at the Palomarin Field Station, near the southern end of the Point Reyes National Seashore, by researchers from PRBO Conservation Science. Their study also included data on 18,052 birds collected between 1983 and 2009, from the Coyote Creek Field Station at the southern end of the San Francisco Bay by the San Francisco Bay Bird Observatory.
“At the time I started my research, a few studies had looked at body size changes in a few species in Europe and the Middle East, but no one had examined bird body size changes in North America,” said Goodman, who now teaches Biology and Environmental Science at San Francisco’s Jewish Community High School of the Bay.
“We had the good fortune to find an unexpected result — a gem in research science,” she added. “But we were then left with the puzzle of figuring out what was going on.”
After testing and discarding a number of other explanations, Goodman and her colleagues were confident that climate change was behind the longer wings and bigger bodies in most of the birds. The birds may be responding to climate-related changes in plant growth or increased climate variability in central California, the researchers suggest in the paper.
“The fingerprint of climate change is showing up in many of our ecosystems,” explains Nat Seavy, research director for the Central Coast at PRBO Conservation Science. “The challenge is to use the long-term data we’ve been collecting to understand how, where and why these changes are occurring.”
The findings offer a glimpse at the potent effects of climate change across a wide range of species, LeBuhn said. “Even over a pretty short period of time, we’ve documented changes in important traits like body size, where we don’t expect to see much flexibility.”
“But in some ways,” she added, “it gave me a little more hope that these birds are able to respond — hopefully in time — to changes in climate.”
“Although it is encouraging that species are changing in response to climate change,” said Seavy, “it is also troubling that environmental stressors are pushing and pulling on species in diverse ways…What will happen to our ecosystems as some species get larger and others get smaller? We need long-term monitoring to help us understand the impact of these changes.”
“Avian body size changes and climate change: warming or increasing variability?” appeared online Oct. 12, 2011, published by Global Change Biology. http://onlinelibrary.wiley.com/doi/10.1111/j.1365-2486.2011.02538.x/full
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I have 52 years of empirical evidence that chilly weather makes my bird small…brrrrr
[SNIP: Site policy requires a valid e-mail address. Please comply. -REP]
That’s why Eskimoes are 7 feet tall and play basketball in the hood and Africans are all 5 feet tall and live in igloos.
This important result proves beyond any reasonable doubt that birds evolved from Amphibians, and not from Reptiles, since both frogs and birds, are now known to grow larger or smaller if temperatures rise or perhaps fall. This study is entirely consistent with such a model.
whew….what a relief
I always wondered why lemmings were so much bigger than capybaras
That extra half a degree can sure work magical results.
Maybe CO2 is good for birds as well as plants! LOL
I watched a program on some PBS station from some University zoology department, that was researching how some kind of rat was slowly migrating to higher elevations as humans slowly encroached on their lower elevation habitats. The scientists concluded that global warming was driving the rats to higher elevations. They claimed that the Temperature had risen 5 deg since the 1950s.
During the program they kept whining about how many species of rats and other such critters had gone extinct down through the years; and they also showed the drawers and drawers of dead rats; hundreds of them that they killed and poked full of wires to stop them rottong and falling apart in the drawers.
Evidently they did not make the connection between their drawers full of hundreds of dead rats, and presumably similar stocks of dead animals in other university drawers, and the fact that some of those dead rats are now extinct.
Evidently zoological student killers are a major threat to the survival of some species of rare animals.
It seems to me that the New Zealand Huia bird, which was noted for the totally different beak designs, for the two sexes, which resulted in totally different diets of the two sexes, likely went extinct in the early 20th century due to ornithologists killing them for samples.
At least in California, our birds are only getting bigger or smaller.
oldseadog says:
October 31, 2011 at 3:00 pm
John Phillips:
Climate Change causes everything.
Potholes in the road, increases in taxation, degredation of roofing tiles, everything.
You forgot to mention the JFK assassination. /sarc
Have that stopped teaching that correlation is NOT causation!
/ikh
So, the CAGW folks said birds would be smaller and now they say they will be bigger?
Well, this isn’t the first time they’ve attempted to “flip us the bird”, is it?
🙂
I’m sorry that NO ONE seems to have caught this one yet. YET another case of the AWG crowd giving us the BIRD. (Apologies to Big Bird and Daffy Duck, both of whom have MORE sense than all the AWG crowd together.)
[REPLY: Sorry, Max. JohnWho beat you to it by just-that-much (TV reference.) -REP]
If these are resident birds, then local or regional change should have more impact than Global Climate Change. Can any of you folks with a good connection and know-how pull up a graph of temperature anomalies for some nearby stations from 1971 to now ? How about precip, wind, cloud cover changes, CO2 concentration ?
Max Hugoson says:
October 31, 2011 at 4:52 pm
I’m sorry that NO ONE seems to have caught this one yet. YET another case of the AWG crowd giving us the BIRD. (Apologies to Big Bird and Daffy Duck, both of whom have MORE sense than all the AWG crowd together.)
[REPLY: Sorry, Max. JohnWho beat you to it by just-that-much (TV reference.) -REP]
I’ll type slower next time, Max.
We “birds of a feather” need to stick together, as they say.
🙂
This is just another case for the list…..http://www.numberwatch.co.uk/warmlist.htm
Does anyone know if he still updates this or not?
birds might get bigger as they store more fat to ride out severe weather events, which are expected to be more common under global climate change
Jeez. Someone needs to explain to them how Natural Selection works.
Only past changes in severe weather events can cause birds to get bigger. Not that there is much evidence more severe weather events have been occurring.
I think the reason birds are getting bigger is a more productive biosphere from increased CO2 levels, And climate change has nothing to do with it.
Plagues of giant yellow birds with mad staring eyes!
We’re doomed!
What warming? The data from BEST study they posted on the Berkeley web site shows that there has been no warming whatsoever during the twenty-first century, in agreement with satellite temperature measurements. Muller tried to hide that fact from the press but it still came out thanks to Judith Curry, an honest member of their team. The only warming satellites actually do see is a short spurt that started in 1998, in four years raised global temperature by a third of a degree, and then stopped. It was oceanic, not greenhouse in nature, and is responsible for the very warm first decade of our century. It is this warming that is responsible for any and all observations of temperature-dependent behavior such as migration, obesity, etc.by birds or animals. These effects do not go back beyond 1998 because there was no warming from the end of World War II until 1998 when a super El Nino warmed us up. Any observations to the contrary are simply in error.
Well, the trees are obviously not conforming to the models, why should the birds…
http://www.physorg.com/news/2011-10-forests-pace-climate.html
Philip Bradley says:
October 31, 2011 at 5:26 pm
I think the reason birds are getting bigger is a more productive biosphere from increased CO2 levels, And climate change has nothing to do with it.
======================
ding ding….we have a winner
‘birds might get bigger as they store more fat to ride out severe weather events, which are expected to be more common under global climate change.’ hilarious, they think birds read peer reviewed nonsense?
I suggest that there is likely no real trend, Rational Debate asks some good questions.
But if there is a real change, it might be because food becomes more abundent in a warmer world.
“it is also troubling that environmental stressors are pushing and pulling on species in diverse ways…”
I’ve seen this directly. My roses bloomed this year when the spring rain stopped. The stressors of dry soil and hot sun pushed and pulled on them in diverse ways, causing them to produce seeds in the belief that they would not survive. It’s the end of the world!!!! Even worse, the end of the world happens every year!!!!! Multi-year apocalypse caused by rapid warming!!!!! We’re doomed!!!!
Bob, Missoula said:
“It has been my impression that almost all global warming studies are either models attempting to prove that yes the earth is heating up and man is responsible or yes the earth is heating up and this is how it will damage, change or eliminate life as we know it.
Wouldn’t it make sense to state clearly and unequivocally that these strategies are not acceptable and prove nothing. So if the above methods aren’t cutting it what kind of study would? The key thought here is what would work, what would convince the majority of skeptics. Has anyone said this is the only style of study that would really prove once and for all that global warming is catastrophic and yes man is responsible. Why wouldn’t it make sense to challenge the best of the best on the other side tell them here are the parameters, show your work and let’s talk.”
They could start by explaining in physical terms how more atmospheric CO2 would increase temperatures.
Apparently the scientific method now boils down too, observe something, propose some conjecture, publish results as fact.
Here is my scientific study. As more AGW research money is available, more studies will proposed AGW as the cause of some marginal change in something.
I’m willing to bet my study has more validity that this bird bs.
Go ask Alice. With apologies in advance to Charles Lutwidge Dodgson and Grace Slick.
One degree makes you larger
One degree makes you small
The one degree in between
Don’t do anything at all
Go ask Alice
When she is ten feet tall
I read a paper that said Dodgson wrote Alice’s Adventures in Wonderland as a critique of the direction that mathematics was being taken at the time. If so he was born too soon, just think what he could create from this material.