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Anthropogenic Sound Effects on Marine Mammals “ How is the U.S. Navy Involved ?”. Anthropogenic Sound Effects on Marine Mammals. The Devastation of Whaling. Anthropogenic Sound Effects on Marine Mammals. Outline. Tragedies Adverted and Current Madness Historical and Scientific Whaling
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Anthropogenic Sound Effects on Marine Mammals“How is the U.S. Navy Involved?”
Anthropogenic Sound Effects on Marine Mammals The Devastation of Whaling
Anthropogenic Sound Effects on Marine Mammals Outline • Tragedies Adverted and Current Madness • Historical and Scientific Whaling • Anthropogenic Noise • Strandings Associated with Mid-Frequency Sonar • Cuvier’s Beaked Whale • Navy Initiatives / Research / Funding
Anthropogenic Sound Effects on Marine Mammals A Huge Problem Averted … Estimated annual number of dolphins killed in the eastern tropical Pacific purse-seine tuna fishery, total for all dolphins and separately for the two dolphin stocks with the highest number killed.
Anthropogenic Sound Effects on Marine Mammals …Yet Another Unchecked • 20,000 dolphins and porpoises are killed each year along the Japanese coast (Taiji) • Japanese Fishermen surround a pod of dolphins then lower metal poles and bang them with hammers • The noise drives the dolphins towards shore, where the killing begins (BBC News, November 8, 2004)
Anthropogenic Sound Effects on Marine Mammals …Yet Another Unchecked • The International Whaling Commission….. Serves whom? • Although banned in 1985, whaling continues to this day • 3 Categories exist: Under Objection, Aboriginal, and Scientific Permit
Anthropogenic Sound Effects on Marine Mammals Aboriginal Whaling (2008-2012) • Bering-Chukchi-Beaufort Seas stock of bowhead whales (taken by native people of Alaska and Chukotka) -A total of up to 280 bowhead whales can be landed in the period 2008 - 2012, with no more than 67 whales struck in any year (and up to 15 unused strikes may be carried over each year). • Eastern North Pacific gray whales (taken by native people of Chukotka and Washington State) - A total catch of 620 whales is allowed for the years 2008 - 2012 with a maximum of 140 in any one year. • East Greenland common minke whales (taken by Greenlanders) - An annual strike limit of 12 whales is allowed for the years 2008 – 2012, with any unused quota available to be carried forward to subsequent years provided that no more than 3 strikes are added to the quota for any one year. • West Greenland bowhead whales (taken by Greenlanders) - An annual strike limit of 2 whales is allowed for the years 2008 - 2012 with an annual review by the Scientific Committee. Any unused quota can be carried forward to subsequent years so long as not more than 2 strikes are added to the quota for any one year. • West Greenland fin whales (taken by Greenlanders) - An annual strike limit of 16 whales is allowed for the years 2010 - 2012. However at the 2010 Meeting Denmark and Greenland agreed to voluntarily reduce further the catch limit for the West Greenland stock of fin whales from 16 to 10 for each of the years 2010, 2011 and 2012. • West Greenland common minke whales (taken by Greenlanders) - An annual strike limit of 178 whales is allowed for the years 2010 - 2012 with an annual review by the Scientific Committee. Any unused quota can be carried forwards so long as no more than 15 strikes are added to the quota for any one year. • West Greenland humpback whales (taken by Greenlanders) – An annual strike limit of 9 whales is allowed for the years 2010-2012 with an annual review by the Scientific Committee. Any unused quota can be carried forwards so long as not more than 2 strikes are added to the quota for any one year. • Humpback whales taken by St Vincent and The Grenadines - For the seasons 2008-2012 the number of humpback whales to be taken shall not exceed 20.
Anthropogenic Sound Effects on Marine Mammals Aboriginal Strike Limit as set by IWC * * (2008-2012)
Anthropogenic Sound Effects on Marine Mammals U.S. Aboriginal Whaling • In the United States, whaling is carried out by nine different indigenous Alaskan communities. • The hunt takes around 50 bowhead whales a year from a population of about 10,500 in Alaskan waters. • Conservationists fear this hunt is not sustainable, though the IWC Scientific Committee, the same group that provided the above population estimate, projects a population growth of 3.2% per year. • The hunt also took an average of one or two gray whales each year until 1996. The quota was reduced to zero in that year due to sustainability concerns. A future review may result in the gray whale hunt being resumed. • The Makah tribe in Washington State also reinstated whaling (gray whales) in 1999, despite protests from animal rights groups.
Anthropogenic Sound Effects on Marine Mammals The Major Global Contribution to Anthropogenic Noise • "Commercial shipping, seismic exploration, sonar technology, marine construction, dredging and seabed drilling have collectively raised background ocean noise to potentially threatening levels. Shipping is the biggest single contributor, through its propeller and engine noise. • Between 1965 and 2003 the world’s commercial fleet doubled in size. Ship noise pollution in the Pacific has doubled every decade for the past 40 years.” • Source: (IFAW Report 2008) (George Frisk / Florida Atlantic University)
Anthropogenic Sound Effects on Marine Mammals Anthropogenic Noise Effects - May cause death or physical injury / hearing loss / stress which leads to detrimental consequences to immune systems and ability to reproduce. - May mask sounds used to locate prey, predators and mates, and navigate. - May cause behavioral changes in breeding and calving and choice of migration routes and feeding grounds.
Anthropogenic Sound Effects on Marine Mammals Noise Overlap with Cetaceans 1- 30 kHz Image Source - Ocean Noise: Turn it down - A report on ocean noise pollution. 2008. IFAW, United States of America.
Anthropogenic Sound Effects on Marine Mammals Why the problem isn’t addressed • Sound from the water (i.e., a propeller on your ship) is reduced in intensity by a factor >1000 as it crosses the air-sea boundary. • We are insulated from the sound of rotating propellers and high intensity SONAR – our ears are in air / MM ears are in water
Anthropogenic Sound Effects on Marine Mammals Sound Properties (Data Source : NOAA)
Sound Properties • Use of I = 10 log [P2/(ZIo)] • When sound propagates from water into air, there is a 30 dB decrease in acoustic intensity because: • Zwater=1,500,000 kg/s-m2 • Zair=415 kg/s-m2 • This is the Acoustic Ceiling!!
Anthropogenic Sound Effects on Marine Mammals StrandingsAssociated with U.S. / NATO Navy Active Sonar • 1989: 20 whales of three species – U.S. Navy - Canary Islands. • 1991: TwoCuvier’s beaked whales - U.S. Navy - Canary Islands. • 1996: Twelve Cuvier’s beaked whales - NATO exercises -Greece. • 1999: Four beaked whales - U.S. Navy - U.S. Virgin Islands. • 2000: A beaked whale U.S. Navy- Vieques. • 2000: Three beaked whales NATO exercises – Madeira (MED) • 2002: A beaked whale and a humpback whale – U.S. Navy - Vieques
Anthropogenic Sound Effects on Marine Mammals StrandingsAssociated with U.S. / NATO Navy Active Sonar • 2002: 14 beaked whales (3 different species) - NATO – Canary. 4beaked whales strand over the next several days. • 2003: 11 harbor porpoises – U.S. Navy - Haro Strait, Washington. • 2004: 6 beaked whales – U.S. Navy – Alaska. • 2004: 200 melon-headed whales – U.S. Navy - Hanalei Bay, Hawaii Rescuers succeed in directing all but one of the whales back out to sea. • 2004: 4 beaked whales – NATO - Canary Islands. • 2005: At least 34 whales of three species – U.S. Navy - Outer Banks. • 2006: 4 beaked whales - NATO - Almeria, Spain.
Anthropogenic Sound Effects on Marine Mammals Beaked Whale • There are 21 species of the Beaked Whale • The Beaked Whale is found in every ocean basin in the world • There families are very small, traveling in groups of about 1 to 5 whales.
Cuvier’s Beaked Whale Images courtesy of Megan Ferguson, Southwest Fisheries Science Center, National Marine Fisheries Service
Anthropogenic Sound Effects on Marine Mammals How has the Navy Responded?
Anthropogenic Sound Effects on Marine Mammals To combat negative effects on sea life, the Navy funds research by universities and nonprofit organizations into how sonar affects marine life. Over the past couple of years, the Navy spent between $10 million and $14 million on research annually, "We fund about 50 percent of marine mammal research worldwide,“ - Rear Adm. Lawrence S. Rice Despite the low numbers (of strandings), the Navy is expanding its marine mammal program and will increase its funding of independent institutions' research to $18 million annually over the next five years.
Questions / Discussion CDR Carl Allen Hager, Ph.D. Assistant Professor Oceanography Department United States Naval Academy Photo – Katherine Whittaker