Acoustic Harassment Devices potential cause for whale strandings

In response to our last article on noise impacts on terrestrial animals, OCR Board Member Seven Lutz sent out this London Times Online article about an increase in bottlenose whales stranding in Whales and Scotland.

One potential cause indicated in the article are the Acoustic Harassment Devices (AHDs) used to keep seals away from fish farms. These are sirens designed to be agonistic to “net predator” seals.

The problem is that the noise doesn’t just affect seals, and in one case mentioned in the article a “disoriented” whale trapped up in a Loch was “only persuaded to leave when a nearby fish farm had turned off its seal-scaring device.” The “persuasions” included playing back a recording of a hunting killer whale (…the dulcet stains of death…)

This all points to the troubling increased in human acoustic impacts on the ocean. It is not just military sonar, seismic surveys, and shipping noise. Increasingly communication and navigation sonar, underwater research equipment, acoustically controlled ROV’s, and AHD’s for aquaculture are becoming part of the harsh acoustic landscape.

Farmed salmon, anyone?