Killer whales, blind bats, discriminating dolphins, mating birds

Animal sounds highlight upcoming Acoustics '08 Paris meeting

June 25, 2008 -- Meek and mighty animal sounds are all around us. In a few weeks, some of the most interesting among them will be discussed and heard at the largest meeting ever devoted to acoustical science, the Acoustics '08 Paris meeting, to be held Monday June 30 through Friday July 4 at the Palais de Congrès in Paris, France.

Animal bioacoustics is just one dimension of Acoustics '08 Paris. It is the field within acoustical science devoted to such things as analyzing the sounds of animals near and far -- the laughing, whooping, and groaning sounds of hyenas, for instance, or the chirp of birdsongs. Another hot area within animal bioacoustics is how sonar and other human sounds affect marine and land animals.

Some of the most interesting animal sounds are those we cannot hear -- like the croaks made by a rare species of frog that communicates ultrasonically or the high-pitched noises bats use to find their way through the dark. Acoustical research helps us better understand the wide world of nature, and it is also guiding the development of new technologies that will improve many people's lives, such as a new sonar device to help the blind navigate their environment.

This news release highlights just a few of the animal bioacoustic talks at Acoustics '08 Paris. More details on the other 3,500 presentations at the meeting and instructions for journalists who wish to cover the meeting are contained at the bottom of this release.

HIGHLIGHTS IN THIS RELEASE

1) How Noise Affects Marine Mammals
2) Birds Changing Their Tune
3) Hyena Giggles and Groans
4) Chinese Frogs Go Ultrasonic
5) Better Recording of Animals in the Wild
6) Bats Can Direct Their "Gaze"
7) How Bats Compensate for Ranging Errors
8) A Sonar System for the Blind
9) Taking Aural Cues from Flipper
10) Acoustic Techniques for Monitoring Bird Migration
11) Conservation and the Tiger's Roar

1) HOW NOISE AFFECTS MARINE MAMMALS

Effects of sonar and other manmade ocean noises on marine mammals have traditionally been defined either as injury or disruption of behavior. The earliest concern was that elevated noise could reduce the range of communication by masking faint signals. Few studies have documented this effect, according to Peter Tyack ( ) of the Woods Hole Oceanographic Institute, but recent work emphasizes the various mechanisms animals use to compensate for elevated noise.

Tyack will present initial results from a study on behavioral responses of beaked whales and other whales to sonar and other sounds. The study was conducted at the Atlantic Undersea Test and Evaluation Center (AUTEC) range near Andros Island in the Bahamas, where beaked whales can regularly be detected using passive acoustic monitoring of their echolocation clicks. The tagged beaked whale responded to both sonar and killer whale sounds by premature cessation of clicking during foraging dives, and an unusually slow and long ascent. [Papers 1aID1 and 1pAB3]