×
ADVERTISEMENT
ADVERTISEMENT
ADVERTISEMENT

Toad is a telltale for impending quakes: scientists

Last Updated 31 March 2010, 04:04 IST
ADVERTISEMENT

The male common toad (Bufo bufo) gave five days' warning of the earthquake that ravaged the town of L'Aquila in central Italy on April 6, 2009, killing more than 300 people and displacing 40,000 others, the study says. Biologist Rachel Grant of Britain's Open University embarked on a toad-monitoring project at San Ruffino lake, 74 kilometres north of L'Aquila, 10 days before the 6.3-magnitude quake struck.

Her two-person team observed the site for 29 days, counting toad numbers and measuring temperature, humidity, wind speed, rainfall and other conditions. By March 28, more than 90 male toads had mustered for the spawning season, but two days later, their numbers suddenly fell, Grant reports.

By April 1 -- five days before the quake -- 96 per cent of the males had fled. Several dozen ventured back on April 9 for the full moon, a known courtship period for toads, although the tally was some 50-80 per cent fewer than in previous years.

After this small peak, the numbers fell once more, only picking up significantly on April 15, two days after the last major aftershock, defined as 4.5 magnitude or higher. In addition, the number of paired toads at the breeding site also dropped to zero three days before the quake. And no fresh spawn was found at the site from April 6 until the last big after-tremor.

ADVERTISEMENT
(Published 31 March 2010, 04:04 IST)

Follow us on

ADVERTISEMENT
ADVERTISEMENT