If a sonar sounds in the sea, but turtles can't hear, does it make a sound?

The Navy held a hearing in Morehead City last night about their plans to build an anti-submarine sonar training range off the NC coast.  According to a Raleigh News & Observer article, 150 people attended the hearing and none spoke in favor of the proposal.

Michelle Nowlin, senior attorney with the Southern Environmental Law Center, sends the following first hand account of the hearing:

There were more than 100 people there, mostly fishermen, but few -- only about 20 -- spoke at the hearing. The Navy had information booths set up, two of which were dedicated to acoustics and their impact on marine mammals. The Navy's primary assertions were: (1) whales hear at ranges below the frequency of the sonar and so wouldn't hear the sonar and thus wouldn't be affected by it; the Navy discounted suggestions that the animals would nonetheless "feel" the sound vibrations; (2) sea turtles can't hear at all and thus will not be affected; they will avoid Sargassum rafts as much as possible; (3) fish also can't hear at the frequency of the sonar... you get the picture.

I talked with the Navy's Natural Resource Manager at length about the pollution from the vessels -- the lead ballast they intend to leave on the ocean floor and the parachutes that will drop the sonabuoys. On both counts, the Navy asserts it would be cost prohibitive to recover these materials, especially when considering the marginal environmental benefit. One of fisherman noted that if these were NC jurisdictional waters, they would not be able to dump trash; the Navy shrugged and said, "well, it's outside NC's jurisdiction and we're in international waters." They were unswayed by the argument that the absence of a law prohibiting them from dumping trash doesn't mean that they SHOULD dump the trash. The Navy disregards concerns about entanglement or drowning of sea turtles in the parachutes. On the lead ballast, their perspective is that (1) the ballast will cover a minuscule portion of the ocean floor, and (2) given the volume of water, there will be no environmental/health impacts from leaching lead. There's evidently a study underway measuring the leaching potential of lead munitions in different undersea environments -- such as sand, silt and hardbottom and calm/turbulent waters -- but they don't plan to wait for the results of the study before moving forward. They said they would consider WQ monitoring, but think it would be cost-prohibitive.

Lots of fishermen raised the lack of information about fin fish as a real concern and provided anecdotal evidence of sensitivity to sound.

One fisherman noted that the sonar would fry the fish-finders and depth-finders that many charter boats use and cited that as a serious economic concern, since these folks live at the economic margins.

According to the N&O article, Nowlin spoke at the hearing, commenting that:

the environmental study grossly underestimated the presence of whales off North Carolina's coast, particularly the right whale. She said the Navy should extend the comment period, which ends Dec. 28, to take into account a report from the Marine Mammal Commission, an independent federal agency, on the effect of sound on sea life.

Visit our previous blog on this topic: Navy vs. NC Wildlife: Round II