http://www.jonesbahamas.com/?c=45&a=8608

According to Dr. Green, impact on other sea life include dolphin strandings, reports from fishermen in England and elsewhere that sonar use decreases their fish catch rate [as does the use of air guns, which has similar intensity to sonar] and giant squid have had exploded organs in an area where air guns are being used.




:shock:

Edited: Link corrected.

corrected link:

http://www.jonesbahamas.com/?c=45&a=8608

are the air guns in question the modern ocean equivalent to fishing with dynamite?

The article doesn't make much distinction between anecdotal and documented evidence, unfortunately, which raises warning flags for me, but that could mean it's sloppy journalism rather than bad science.

Here's another link on the topic.
http://www.nrdc.org/media/pressReleases/051121.asp

Here's a good one from NOAA on undersea noise.
http://www.oceanexplorer.noaa.gov/explorations/sound01/background/seasounds/seasounds.html