Nav: Home

Study finds 2 billion birds migrate over Gulf Coast

January 09, 2019

Ithaca, NY-- A new study combining data from citizen scientists and weather radar stations is providing detailed insights into spring bird migration along the Gulf of Mexico and how these journeys may be affected by climate change. Findings on the timing, location, and intensity of these bird movements are published in the journal Global Change Biology.

"We looked at data from thousands of eBird observers and 11 weather radar stations along the Gulf Coast from 1995 to 2015," says lead author Kyle Horton, an Edward W. Rose Postdoctoral Fellow at the Cornell Lab of Ornithology. "We calculated that an average of 2.1 billion birds crosses the entire length the Gulf Coast each spring as they head north to their breeding grounds. Until now, we could only guess at the overall numbers from surveys done along small portions of the shoreline."

eBird is the Cornell Lab's worldwide online database for bird observation reports. Sightings from bird watchers helped researchers translate their radar data into estimates of bird numbers. Weather radar detects birds in the atmosphere in a standardized way over time and over a large geographical area.

The radar data reveal when birds migrate and what routes they take. The timing of peak spring migration was consistent over 20 years along the 1,680-mile coastline. But the researchers found that the 18-day period from April 19 to May 7 was the busiest--approximately one billion birds passed over the Gulf Coast in that time span. Not all locations were equally busy, with key hotspots showing significantly higher levels of activity.

The highest activity, with 26,000 birds per kilometer of airspace each night, was found along the west Texas Gulf Coast," says Horton. "That region had 5.4 times the number of migrants detected compared with the central and eastern Gulf Coast from Louisiana to Florida." The data show Corpus Christi and Brownsville as having the highest level of migration traffic along the western coast of Texas.

Knowing where and when peak migration occurs means efforts can be made to turn off lights and wind turbines, which are known threats to migratory birds.

Migration timing is also critical for birds. Although migration has evolved in the past as climates changed, the current rate of change may be too rapid for birds to keep pace. This study shows that the earliest seasonal movements are starting sooner, advancing by about 1.5 days per decade, though peak activity timing hasn't changed, which may be cause for concern. These findings provide important baseline information that will allow scientists to assess the long-term implications of climate change for migratory birds.

"If birds aren't changing their migration timing fast enough to match the timing for plants and insects, that's alarming," Horton says. "They may miss out on abundant resources on their breeding grounds and have less reproductive success."

Scientists from the Cornell Lab of Ornithology, the University of Oxford, the Smithsonian Migratory Bird Center, the University of Delaware, and the University of Oklahoma conducted this research.
-end-
Funding for this project was provided by the Rose Postdoctoral Fellowship, Leon Levy Foundation, National Science Foundation, and Southern Company through their partnership with the National Fish and Wildlife Foundation.

Reference: Kyle Horton, Benjamin Van Doren, Frank La Sorte, Emily Cohen, Hannah Clipp, Jeffrey Buler, Jeff Kelly, and Andrew Farnsworth. (2018) Holding steady: little change in intensity or timing of bird migration over the Gulf of Mexico. Global Change Biology.

Cornell University

Related Climate Change Articles:

Fairy-wrens change breeding habits to cope with climate change
Warmer temperatures linked to climate change are having a big impact on the breeding habits of one of Australia's most recognisable bird species, according to researchers at The Australian National University (ANU).
Believing in climate change doesn't mean you are preparing for climate change, study finds
Notre Dame researchers found that although coastal homeowners may perceive a worsening of climate change-related hazards, these attitudes are largely unrelated to a homeowner's expectations of actual home damage.
Older forests resist change -- climate change, that is
Older forests in eastern North America are less vulnerable to climate change than younger forests, particularly for carbon storage, timber production, and biodiversity, new research finds.
Could climate change cause infertility?
A number of plant and animal species could find it increasingly difficult to reproduce if climate change worsens and global temperatures become more extreme -- a stark warning highlighted by new scientific research.
Predicting climate change
Thomas Crowther, ETH Zurich identifies long-disappeared forests available for restoration across the world.
More Climate Change News and Climate Change Current Events

Best Science Podcasts 2019

We have hand picked the best science podcasts for 2019. Sit back and enjoy new science podcasts updated daily from your favorite science news services and scientists.
Now Playing: TED Radio Hour

Erasing The Stigma
Many of us either cope with mental illness or know someone who does. But we still have a hard time talking about it. This hour, TED speakers explore ways to push past — and even erase — the stigma. Guests include musician and comedian Jordan Raskopoulos, neuroscientist and psychiatrist Thomas Insel, psychiatrist Dixon Chibanda, anxiety and depression researcher Olivia Remes, and entrepreneur Sangu Delle.
Now Playing: Science for the People

#537 Science Journalism, Hold the Hype
Everyone's seen a piece of science getting over-exaggerated in the media. Most people would be quick to blame journalists and big media for getting in wrong. In many cases, you'd be right. But there's other sources of hype in science journalism. and one of them can be found in the humble, and little-known press release. We're talking with Chris Chambers about doing science about science journalism, and where the hype creeps in. Related links: The association between exaggeration in health related science news and academic press releases: retrospective observational study Claims of causality in health news: a randomised trial This...