Featured Research

from universities, journals, and other organizations

Songbirds migrate on strict schedule

Date:
July 25, 2012
Source:
York University
Summary:
A new study finds that songbirds follow a strict annual schedule when migrating to their breeding grounds – with some birds departing on precisely the same date each year.

This is a wood thrush in Belize.
Credit: Kevin Fraser

A new study by York University researchers finds that songbirds follow a strict annual schedule when migrating to their breeding grounds -- with some birds departing on precisely the same date each year.

The study, published in the journal PLoS ONE, is the first to track the migration routes and timing of individual songbirds over multiple years. Researchers outfitted wood thrushes with tiny geolocator "backpacks," recording data on their movements.

Spring departure dates of birds heading from the tropics to North American breeding grounds were surprisingly consistent, with a mean difference of only three days from year to year, the study reports. Fall migration, however, was far less predictable. Males on average flew faster than females, and first-timers lagged behind those with more than one journey under their wings.

The geolocators, which are smaller than a dime, are mounted on birds' backs with thin straps looped around their legs. The devices measure light, allowing researchers to estimate latitude and longitude by recording sunrise and sunset times.

"It's quite surprising that the schedules of these birds are so consistent across the entire route, with some of them departing the tropics and arriving at breeding sites in North America on the same day in different years," says study author Kevin Fraser, a postdoctoral Fellow in York's Department of Biology, Faculty of Science & Engineering. "Much like airplanes, there are many factors that can influence birds' flight schedules, such as weather at departure and expected conditions at the other end of the journey. Amazingly, these small songbirds are highly consistent in their timing between years."

Interestingly, while their departure times are precise, songbirds' migratory routes can vary widely. "Migratory routes sometimes differed by several hundred kilometres between years, which may reflect a fine-tuning of migration in response to wind and weather conditions en route, such as during large open-water crossings like the Gulf of Mexico," he says.

As for arrival times, birds need to be early to lay their claim to prime breeding grounds -- but not too early.

"There is intense pressure for birds to get back to breeding grounds early to secure good territories, nest sites and, of course, mating opportunities. The early birds tend to do better and raise more young. However, cool weather in early spring can reduce food availability and even survival of early birds," Fraser says. He cautions that songbirds' consistent timing may come at a cost.

"The concern is that birds may not be able to flexibly adjust their schedules to meet new conditions with climate change," says Fraser. "This is a topic we're pursuing in current research."

The birds Fraser tracked were tagged in Pennsylvania and Costa Rica, at field research sites of his supervisor, York University Professor Bridget Stutchbury, who has studied the behavioural ecology of birds for decades. Her 2007 book, Silence of the Songbirds, details the threat to the species posed by climate change and habitat destruction.

"Numbers [of wood thrush] have plummeted in Canada by over fifty percent since the 1960s. When we lose the wood thrush, and other songbirds, we lose an integral part of the forest itself," Stutchbury says.


Story Source:

The above story is based on materials provided by York University. Note: Materials may be edited for content and length.


Journal Reference:

  1. Calandra Q. Stanley, Maggie MacPherson, Kevin C. Fraser, Emily A. McKinnon, Bridget J. M. Stutchbury. Repeat Tracking of Individual Songbirds Reveals Consistent Migration Timing but Flexibility in Route. PLoS ONE, 2012; 7 (7): e40688 DOI: 10.1371/journal.pone.0040688

Cite This Page:

York University. "Songbirds migrate on strict schedule." ScienceDaily. ScienceDaily, 25 July 2012. <www.sciencedaily.com/releases/2012/07/120725200332.htm>.
York University. (2012, July 25). Songbirds migrate on strict schedule. ScienceDaily. Retrieved September 21, 2014 from www.sciencedaily.com/releases/2012/07/120725200332.htm
York University. "Songbirds migrate on strict schedule." ScienceDaily. www.sciencedaily.com/releases/2012/07/120725200332.htm (accessed September 21, 2014).

Share This



More Plants & Animals News

Sunday, September 21, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Raw: San Diego Zoo Welcomes Cheetah Cubs

Raw: San Diego Zoo Welcomes Cheetah Cubs

AP (Sep. 20, 2014) The San Diego Zoo has welcomed two Cheetah cubs to its Safari Park. The nearly three-week-old female cubs are being hand fed and are receiving around the clock care. (Sept. 20) Video provided by AP
Powered by NewsLook.com
Chocolate Museum Opens in Brussels

Chocolate Museum Opens in Brussels

AFP (Sep. 19, 2014) Considered a "national heritage" in Belgium, chocolate now has a new museum in Brussels. In a former chocolate factory, visitors to the permanent exhibition spaces, workshops and tastings can discover derivatives of the cocoa bean. Duration: 01:00 Video provided by AFP
Powered by NewsLook.com
Could Grief Affect The Immune Systems Of Senior Citizens?

Could Grief Affect The Immune Systems Of Senior Citizens?

Newsy (Sep. 19, 2014) The study found elderly people are much more likely to become susceptible to infection than younger adults going though a similar situation. Video provided by Newsy
Powered by NewsLook.com
Jury Delivers Verdict in Salmonella Trial

Jury Delivers Verdict in Salmonella Trial

AP (Sep. 19, 2014) A federal jury has convicted three people in connection with an outbreak of salmonella poisoning five years ago that sickened hundreds of people and was linked to a number of deaths. (Sept. 19) Video provided by AP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins