16 September 2012
Source: National Geographic
Author: Amy Bucci
“The oceans cover 71 percent of our planet,yet only five percent of it has been explored.” —Dr. Robert Ballard
On Sunday, September 16th, National Geographic Channel aired “Alien Deep” featuring Dr. Bob Ballard, and his expeditions on the E/V Nautilus. We interviewed one of the chief scientists from the show and expedition leader Dr. Mike Brennan to get to the bottom of one of the major threats to the future of ocean exploration: mobil fishing gear or bottom trawls.
What are the effects you are seeing on shipwrecks as a result of bottom trawls?
Unfortunately, on the E/V Nautilus expeditions, we have seen that many of the wrecks in the Aegean and Black Seas are heavily damaged by trawling activity. For example, one shipwreck, Eregli E, is the most trawled shipwreck in the Black Sea based upon scatter and damage to the artifacts and surrounding seabed. When we found it last year we saw that it was really damaged. The site had been so disturbed, it uncovered materials from beneath the sediment, including human bones. The bones had been preserved in the mud, but then had been ripped out by trawls and that’s why we actually could see them. When we returned this year the artifacts we had seen the year before were either further damaged or gone, including the bones that were completely missing, again due to trawling. (Learn More: Ancient shipwrecks lost to trawlers.)
How exactly do you quantify the damage to sunken shipwrecks?
We can see the intensity of trawl scars using side-scan sonar mapping, and visibly see the dispersal of wooden timbers, and broken ceramic cargo. We’ve gathered data on where fishing vessels are versus trawl intensity. (See: Quantification of Trawl Damage to Premodern Shipwreck Sites)
For more, go to: http://newswatch.nationalgeographic.com/2012/09/16/deep-sea-trawling-effecting-shipwrecks-of-alien-deep/