Study underway to quantify the issue of noise pollution and Orcas. From this, could come regulations that force shipping to alter course if Orcas are within certain distances from ships.
When an endangered orca is in hot pursuit of an endangered salmon, sending out clicks and listening for their echoes in the murky ocean near Seattle, does the noise from the nearby shipping lane interfere with them catching dinner? To find out scientists measured underwater noise as ships passed their study site 3,000 times. This unprecedented characterization of ship noise will aid in the understanding of the potential effects on marine life, and help with possible mitigation strategies. One of the threats faced by today’s oceans is underwater noise pollution from ships. Amazingly, the growth in commercial shipping has raised the intensity of low-frequency noise almost 10-fold since the 1960s. Because this noise occurs at the low frequencies used by baleen whales there is growing evidence it may impact their ability to communicate, and therefore their survival. But could ship noise extend to the higher frequencies used by toothed whales and therefore pose similar threats to them? To answer this question and understand the nature of ship noise, particularly in coastal areas where ships access ports, scientists measured approximately 1,600 unique ships as they passed through Haro Strait, in Washington State. This area is the core critical habitat for the endangered Southern Resident killer whales—salmon-eating orcas which are iconic in the Pacific Northwest and which support a multi-million dollar ecotourism industry in the U.S. and Canada. (Phys.Org)
http://phys.org/news/2016-02-ship-noise-frequencies-endangered-killer.html
Filed under: Orcas, Puget Sound | Tagged: Puget Sound |
