Drop in daddy long legs is devastating bird populations

[Sally Furniss]

Drop in daddy long legs is devastating bird populations

Warm summers are dramatically reducing populations of daddy long legs, which in turn is having a severe impact on the bird populations which rely on them for food.
New research by a team of UK scientists spells out for the first time how climate change may affect upland bird species like the golden plover ? perhaps pushing it towards local extinction by the end of the century.
It also points a way forward to how we can attempt to strengthen habitats to help wildlife adapt to our changing climate and prevent such consequences.
Previous research has shown how changes in the timing of the golden plover breeding season as a result of increasing spring temperatures might affect their ability to match the spring emergence of their cranefly (daddy long legs) prey.
The new research, published today in the scientific journal Global Change Biology and led by Dr James Pearce Higgins of the Royal Society for the Protection of Birds (RSPB) Scotland, shows the true effects are much more severe.
Higher temperatures in late summer are killing the cranefly larvae, resulting in a drop of up to 95 per cent in the number of adult craneflies emerging the following spring. With these craneflies providing a crucial food source for a wide range of upland birds like the golden plover, this means starvation and death for many chicks.
Newcastle University's Dr Mark Whittingham, one of the authors of the research, said: "The population of Golden Plovers in our study will likely be extinct in around 100 years if temperature predictions are correct and the birds cannot adapt to feed on other prey sources.
"Our study models the impacts of climate change on the ecology of the animal. In this case we show that higher August temperatures, as predicted from climate change models, are correlated with lower numbers of daddy-long legs.
"Daddy long-leg abundance is key for Golden Plover chicks in terms of growth and survival. Worryingly, our work is likely to apply to other upland bird species that also rely on daddy-long legs as a prey resource, such as Curlew."
Dr James Pearce Higgins added: "Many studies predict dire effects of climate change upon wildlife but this study provides a rare example of where such predictions are based on a detailed understanding of a species' requirements, linking the effects of climate on food resources to changes in breeding success and population size.
"This is the most worrying development that I have found in my scientific career to date. However, by understanding these processes, we now have the chance to respond. If we can maintain good quality habitats for craneflies then we can help the birds too. For example, by blocking drainage ditches on our Forsinard reserve in the North of Scotland we hope to raise water levels and reduce the likelihood of the cranefly larvae drying out in hot summers.
"The fight against climate change will increasingly mean strengthening habitats to protect vulnerable species, as well as trying to reduce emissions."


http://www.eurekalert.org/pub_releases/2009-03/nu-did032609.php

 

[AlaskaDenise]

Re: Drop in daddy long legs is devastating bird populations

Daddy long legs in trouble too? Amazing that so many of our little creatures are in danger.

.....if temperature predictions are correct and the birds cannot adapt to feed on other prey sources.

The key - they must adapt.

I'd expect numbers to plunge until the surviving smart and/or flexible members of their species produce enough offspring to bring the population up to whatever the new conditions can support.

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[tropical]

Re: Drop in daddy long legs is devastating bird populations

Daddy long legs in trouble too? Amazing that so many of our little creatures are in danger.

The key - they must adapt.

I'd expect numbers to plunge until the surviving smart and/or flexible members of their species produce enough offspring to bring the population up to whatever the new conditions can support.
.

Sorry AD., but that's the catch - they can't adapt in such short evolution time period
- that's one of the reasons why many species already disappeared.


And that's why the global climatic change is so dangerous.

 

[AlaskaDenise]

Re: Drop in daddy long legs is devastating bird populations

They are already examples of birds that have currently adapted to climate change. There have been times when there were sudden climate changes and not all birds became extinct - they adapted.

One example is the Pied Flycathcer, and it's adaptation is described here. Some swallows also have the genetic variation that allow them to easily adapt. Some species are already opportunistics migrants and can adapt easilye.g., snowy owl, red polls, some warblers, etc.

Scientists in the north discovered some birds had adapted by migrating further north prior to widespread human knowledge of global warming - the birds knew what was happening and were already changing.

My point above is that the entire population of a species may not successfully adapt initially, but those who do will eventually increase the population.

Many animals are for more flexible than what we think.

There was an article posted on FT some time ago about the ongoing adaptation of many species. Some impediments, like cities, do create problems for land migrants.

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[Sally Furniss]

Re: Drop in daddy long legs is devastating bird populations

Was it this one?
http://www.flutrackers.com/forum/showthread.php?p=186758

 

[AlaskaDenise]

Re: Drop in daddy long legs is devastating bird populations

Update: There are about 7000 species of daddy long legs - all a little different, adapted to a unique niche. The daddy long legs here generally winter in our crawl spaces, but there is at least one new species that survives in extremely cold remote locations.

.

 

[Sally Furniss]

Re: Drop in daddy long legs is devastating bird populations

Insect Population Growth Likely Accelerated By Warmer Climate

ScienceDaily (Oct. 31, 2006) — Insects have proven to be highly adaptable organisms, able through evolution to cope with a variety of environmental changes, including relatively recent changes in the world's climate. But like something out of a scary Halloween tale, new University of Washington research suggests insects' ability to adapt to warmer temperatures carries an unexpected consequence -- more insects.

It appears that insect species that adapt to warmer climates also will increase their maximum rates of population growth, which UW researchers say is likely to have widespread affects on agriculture, public health and conservation.
Many studies have shown that insects readily adapt to the temperature of their environment. For example, those living in deserts easily tolerate high temperatures but are much less tolerant of cold temperatures than insects living in mountains. Now UW biology researchers have found that insect species that have adapted to warmer environments also have faster population growth rates. The research shows, in effect, that "warmer is better" for insects, said Melanie Frazier, a UW biology doctoral student.
"Enhanced population growth rates for butterflies might be a good thing, but enhanced growth rates for mosquito populations is much more dubious," said Frazier, who is lead author of the new research, published in the October edition of the journal The American Naturalist.
Co-authors are Raymond Huey, a UW biology professor, and David Berrigan, a former UW biology researcher now with the National Cancer Institute.
The findings suggest that evolutionary adaptation to climate warming will have profound ecological effects because rates of population growth eventually will alter entire ecosystems, Frazier said. In addition, key ecosystem characteristics such as species diversity and food webs are very sensitive to the population growth rates of the species living and interacting in those ecosystems.
She noted that biochemical adaptation to warmer temperature is not the only possible insect response to climate warming. Some species might evade warmer temperatures by moving to cooler habitats, or they might alter their seasonal activity patterns. Others might not be able to adapt adequately and could become extinct. But those that do adapt should have elevated rates of population growth.
"No matter which scenario plays out for a given species, local ecosystems will be profoundly altered," Frazier said.

http://www.sciencedaily.com/releases/2006/10/061030143411.htm

 

[Sally Furniss]

Re: Drop in daddy long legs is devastating bird populations

Abstract from the daddy long legs paper

Impacts of climate on prey abundance account for fluctuations in a population of a northern wader at the southern edge of its range

JAMES W. PEARCE-HIGGINS ^{<nobr>*</nobr>} , PETER DENNIS†, MARK J. WHITTINGHAM‡ and DEREK W. YALDEN§

ABSTRACT

Understanding the mechanisms by which climate change will affect animal populations is vital for adaptive management.

Many studies have described changes in the timing of biological events, which can produce phenological mismatch.

Direct effects on prey abundance might also be important, but have rarely been studied.

We examine the likely importance of variation in prey abundance in driving the demographics of a European golden plover (Pluvialis apricaria) population at its southern range margin.

Previous studies have correlated plover productivity with the abundance of their adult cranefly (Tipulidae) prey, and modelled the phenology of both plover breeding and cranefly emergence in relation to temperature.

Our analyses demonstrate that abundance of adult craneflies is correlated with August temperature in the previous year.

Correspondingly, changes in the golden plover population are negatively correlated with August temperature 2 years earlier.

Predictions of annual productivity, based on temperature-mediated reductions in prey abundance, closely match observed trends.

Modelled variation in annual productivity for a future scenario of increasing August temperatures predicts a significant risk of extinction of the golden plover population over the next 100 years, depending upon the magnitude of warming.

Direct effects of climate warming upon cranefly populations may therefore cause northward range contractions of golden plovers, as predicted by climate envelope modelling.

Craneflies are an important food source for many northern and upland birds, and our results are likely to have wide relevance to these other species.

Research into the potential for habitat management to improve the resilience of cranefly populations to high temperature should be an urgent priority.

http://www3.interscience.wiley.com/journal/121684866/abstract

 

[AlaskaDenise]

Re: Drop in daddy long legs is devastating bird populations

From #7:

But those that do adapt should have elevated rates of population growth.

An insect "superspreader."

.

 

[AlaskaDenise]

Re: Drop in daddy long legs is devastating bird populations

Birds Migrating Further North: Researchers Blame Global Warming

As if scientists needed any further proof of global warming, zoologists have spotted a new trend in the migration pattern of many birds, suggesting that the birds are altering their migratory habits to spend their winters further north than ever before. As the average temperatures in the US have increased over the past decades, many migratory birds, such as the Finch, have been altering their winter migration. In fact, the Finch now migrates 400 miles north of its previous winter home.
The American Audubon Society has released a research study which concluded that over 150 species of birds throughout North America have shifted their migration further North. Birds such as Robins, Finches, Seagulls, and even Owls are now wintering further north than ever before.

Of course, there are many factors that can affect bird migration patterns, including deforestation, pollution, and our urban sprawl. However, researchers for the Audubon Society that global warming is the only logical way to explain how so many different species of birds have moved their migration patterns northward.

The Audubon Society study took a look at bird migration statistics and weather patterns over a 40 year period. They determined that average temperatures have jumped significantly, climbing approximately 5? on average during the month of January. The northern United States has seen the most pronounced ?warming? and as a result, many species of birds from northern areas are staying closer to home in the winter.

However, the study?s findings were not news at all too many dedicated birdwatchers, who have noticed for decades that birds of all types have been shifting their migrations further north. Similar studies conducted in the United Kingdom also suggest that bird migration is changing rapidly.

Not all species are moving further north, however. And scientists remain baffled why some species have shifted their migration by as much as 400 miles ? while others seemingly haven?t budged an inch. The recent Audubon Society study suggests that as many as half of North American bird species have altered their migration pattern further north.

Some birds, such as the Carolina Wren, have drastically altered their migration, and are now more common in the northeastern United States than they are in the Carolinas (the very area they were named after). Birdwatchers in the Carolinas have noted that the Carolina Wren is now rarely spotted in the area, while they appear to be plentiful in Maine and throughout New England.

Researchers say the evidence is overwhelming, and the obvious shift in bird migration patterns is proof positive that global warming is both real and increasing.

http://www.edubook.com/birds-migrating-further-north-researchers-blame-global-warming/2941/