Climate Change Shifts Bird Migration—One Generation at a Time
Biologists unravel how warming weather causes some birds to migrate earlier.
In the last few decades birders and biologists alike have noticed that spring migration is changing. Species are arriving on their breeding grounds earlier each year. It’s clear there’s a link between climate change and shifting travel dates, but a new study reveals that individual black-tailed godwits are very consistent in their migratory timing, challenging assumptions about how warmer weather shifts behavior.
These leggy, reddish shorebirds winter in Spain and Portugal. They return to their Icelandic breeding grounds each spring, between mid-May and mid-April, often nesting a month after arrival. A team of biologists who closely track their movements have noted that the birds arrive two weeks earlier today than they did twenty years ago.
To figure out why, they first tackled the long-held assumption that balmier weather might trigger individual birds to take flight sooner each season. Poring over 14 years of records for 54 individual godwits, they discovered something curious: Each bird returned year after year on roughly the same day.
What did change was the birds’ nesting date.
Dramatic video by NYTimes on Chinese government’s heavy handed plan to move 250,000,000 people to cities. That’s pretty close to the size of the entire population of the United States.
How prepared are American cities for increased natural disasters? Over the years, Americans have insisted on expanding and building cities and suburbs in locations that are clearly threatened by natural hazards. This week’s monster tornado in Oklahoma demonstrates this. Cities and states have encouraged people to live in these areas through city planning, architectural design, and the so-called need for “economic development.”
Thus, instead of encouraging people to not live in these hazard zones, city leaders have created methods to help people survive relatively normal lives there. Houses in California must meet specific earthquake design standards, buildings in Oklahoma have “safe rooms,” and countless structures must be stable enough to handle floods and erosion along American coastlines. These are adaptations. Not good adaptations (I believe people should not be encouraged to live in these areas), but there it is.
With the climate changing, the impacts on communities are likely to increase. Incidences of natural disasters are expected to rise, costing many lives and causing a need for an endless stream of disaster aid.
Researchers at MIT teamed up with the non-profit ICLEI to survey cities around the world. The goal was to compare how they were adapting to climate change impacts, or preparing for future impacts. Progress, the researchers found, is very slow in the US, while cities around the world are far more advanced.
It’s a great read, very visual so if you don’t have time you can skim it.
Survey: U.S. Cities Report Increase in Climate Change Impacts, Lag Global Cities in Planning
It’s March, which means the sandhill cranes are back to roost at Nebraska’s Central Platte River.
Photo by Chris Helzer/TNC.
Read more at the Prairie Ecologist.
Wow! Wish I could see this beautiful spectacle.
“Invasive Species." A clever tree made it onto Canada’s currency.
"It’s a species that’s invasive in Eastern Canada and is displacing some of our native species, and it’s probably not an appropriate species to be putting on our native currency," Blaney told CBC News. Sean Blaney, senior botanist of the Atlantic Canada Conservation Data Centre, said he never expected to see the Norway maple leaf on a $20 bill.
The bank’s response is equally amusing…
Something is amiss! I witnessed about 300 Canadian Geese migrating NORTH today. Are they drunk? Is winter over? I can’t figure out the exact migration period for these species to return north but surely it’s not January, three weeks after winter started!
Fantastic map of Sahel movement and conflict. Natural resources and migration are the biggest drivers of both economic development and conflict in the region. But, over the past decade or so, both have escalated exponentially. Expect more conflict as the climate changes and water resources are more strictly controlled.
Via the Arabist
As the climate warms, plant species that prefer a colder environment are disappearing from the mountain ranges of Southern Europe. Since many of these species have small distribution areas, they are now threatened with extinction, according to two new studies from European researchers.
"These species have migrated upwards, but sooner or later the mountain reaches its summit," said researcher and biologist Ulf Molau at Sweden’s University of Gothenburg. "Many alpine plant species are disappearing from mountain ranges in Southern Europe, and for some of them - those that are only found in a single mountain range - the outlook is extremely bleak."
Over a period of 10 years, researchers around Europe have gathered samples from 13 different mountain regions.
Using digital technology and intensive on-site field work, they have been able to study a grid pattern of square meters, selected on different high mountain summits, from the treeline up to the highest peaks.
The digital photographs provide a detailed picture of which species have disappeared between 2001 and the present day.
"Every research square is digitally photographed so that we can find our way back to the exact same position after 10 years or more, with centimeter precision," said Professor Molau. "By rolling out an analysis network, small 10 x 10 cm squares can be re-mapped."
Today, the researchers are able to observe that species are migrating upwards and that the variety of species in Southern European mountain regions has declined during the 10 years in which samples have been taken.
"This finding confirms the hypothesis that a rise in temperatures drives Alpine flora to migrate upwards. As a result, rival species are threatened by competitors, which are migrating to higher altitudes. These changes pose a threat to high-mountain ecosystems in the long and medium term," the authors state.
Follow Climate Adaptation.
"Some birds are adjusting their migration patterns and adapting to climate change better than others, researchers found.
A study of bird flight patterns found that while some shift their migration as much as six days earlier in warmer weather, others are keeping the same habits, according to a report in the Public Library of Science.
Birds that aren’t adapting, like the Barn Swallow, could be threatened if the crop of insects they feed on aren’t available at the same time, for example, said Allen Hurlbert, the lead author, in a telephone interview.
“This is a new threat,” said Hurlbert, an assistant professor of biology at the University of North Carolina at Chapel Hill. “It’s an additional risk factor for the health of their population.”
Hurlbert’s study of 18 bird species is the first to examine the entire Eastern United States, he said. It’s also unique in using citizen bird watching data from more than 50,000 people logging into eBird, an online site created in 2002 by the Cornell Lab of Ornithology and the National Audobon Society.
On average, the birds shifted their migration almost a day earlier for every Celsius degree of warming spring temperature. Species that fail could be eliminated through natural selection.”
This is the last resort, there’s no way out of this one.
Anote Tong - President of Pacific island nation Kiribati, on the rising sea levels that are threatening his homeland and could force the entire nation to relocate to Fiji.
Climate change … it’s happening.
More: Entire nation of Kiribati to be relocated over rising sea level threat