Chernobyl radiation fells female birds, making chirping more frequent from lonely bachelors

Apr 20, 2012 By Steven Powell
Anders Moller (left) and Tim Mousseau (center) measure barn swallows while a farmhand looks on at a collective farm near Chernobyl.

Birdsong is one of the joys of nature, but higher percentages of birds chirping near Chernobyl are a perverse indication of radiation contamination, according to a new study.

An international team of researchers studied gender abundances and singing behavior in birds from eight areas with varying levels of radiation contamination near Chernobyl, Ukraine, the center of the catastrophe that began with an explosion in a on April 26, 1986.

The results, published in PLoS One, were clear: higher levels of contamination went hand-in-hand with greater male-to-female ratios.

"We're seeing higher mortalities for females than males, reflecting the increased costs of reproduction in these stressful environments," said co-author Timothy Mousseau, a professor of biological sciences in the College of Arts and Sciences at the University of South Carolina. Male bird mortality also increased with background , he added, but the female susceptibility to contamination was far stronger.

Counting the number of birds singing in each area, the researchers found that the percentage chirping was higher in the more contaminated areas. Given the relative dearth of females in those areas, the team concluded that lonely bachelors were spending more time calling out for mates.

That observation means that some earlier Chernobyl data might beg an even more stark interpretation. "When we did the original censuses, the standard method for doing a bird count is birds that you can either see or hear," Mousseau said. "So our early estimates of abundance were probably overestimates in the contaminated areas."

The data also showed higher percentages of yearlings, rather than more mature birds, in the areas of higher contamination.

"It's what we've seen for many years now," said Mousseau, the director of the Chernobyl Research Initiative at USC, which has sponsored studies on the long-term ecological and health consequences of the since 1998, including many collaborations with this paper's co-author Anders Møller of the CNRS in France.

"Within the Chernobyl zone, it's very heterogeneous – where the contamination levels are high, there are far fewer birds."

The team captured and examined to determine their sex in regions with background radiation ranging from 0.02 to 138 micro-Sv per hour (0.02 to 0.05 micro-Sv per hour are normal levels in the northern Ukraine).

Explore further: How ferns adapted to one of Earth's newest and most extreme environments

More information: PLoS ONE 7(4): e35223. doi:10.1371/journal.pone.0035223

Journal reference: PLoS ONE search and more info website

Provided by University of South Carolina

4.5 /5 (4 votes)
add to favorites email to friend print save as pdf

Related Stories

Brightly colored birds most affected by Chernobyl radiation

Jul 11, 2007

Brightly coloured birds are among the species most adversely affected by the high levels of radiation around the Chernobyl nuclear plant, ecologists have discovered. The findings – published online in the British Ecological ...

Less radiation damage in Chernobyl lakes than feared

Apr 21, 2011

(PhysOrg.com) -- A new study of the lakes in and around Chernobyl's fallout zone reveals that radiation from the nuclear accident appears to have had no long term effect on the abundance or diversity of aquatic animal life.

Greenpeace says Chernobyl food radiation persists

Apr 04, 2011

(AP) -- Greenpeace said Monday that hundreds of thousands of Ukrainians are still eating food contaminated by radiation from the Chernobyl nuclear power plant explosion a quarter-century after the blast.

Recommended for you

Cat dentals fill you with dread?

8 hours ago

A survey published this year found that over 50% of final year veterinary students in the UK do not feel confident either in discussing orodental problems with clients or in performing a detailed examination of the oral cavity ...

User comments : 0