Study confirms greater harm to beaked whales from sonar than previously admitted by government

For years, the U.S. Navy has heavily contested evidence that sonar harms marine mammals at lower exposure levels and the National Marine Fisheries Service (NMFS) has been aiding and abetting this “if I close my eyes maybe it will go away” behavior.  But now, new evidence from research funded and conducted in part by the Navy and NMFS confirms that beaked whales are harmed by sonar at exposure levels much lower than those used by the government to estimate harm caused by Navy sonar.  This evidence will be much harder for the Navy and NMFS to dodge and should trigger a reassessment of the impacts Navy training has on the environment and modifications to NMFS’ authorizations of Navy training activities that harm millions of marine mammals each year.

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The research, summarized in the paper, Beaked Whales Respond to Simulated and Actual Navy Sonar (written by Peter L. Tyack et al. and published in PLoS ONE on March 14, 2011) shows that beaked whales ceased vocalizing, ceased foraging, and fled when exposed to actual and simulated sonar at levels well below those used by the Navy and NMFS to define behavioral disturbance.  The habitat abandonment was particularly noteworthy as several days passed before the beaked whales returned and renewed their vocalizing to pre exposure levels.  And what made these behavioral alterations all the more striking was the fact that the experiments were conducted on a Navy range that regularly hosts naval sonar exercises, suggesting that the beaked whale population is regularly exposed to sonar, yet still exhibited significant behavioral changes.

It is hard to know whether this research will affect the government’s position on acceptable levels of harm to beaked whales and other marine mammals as a sacrifice for the Navy’s complete and unfettered access to millions of square miles of ocean, but one thing is for sure – previous estimates of beaked whales harmed by sonar were categorically underestimated and its possible that the same is true for all whales and dolphins.

Despite the magnitude of this new science and the harm sonar has had on beaked whale populations, without this research we would still be working under the assumption that most beaked whales were only affected by sonar at much higher levels of exposure.  While this study will definitely trigger a reassessment of sonar impacts on beaked whales, I hope it also leads the Navy and NMFS to reassess their understanding of sonar exposure and the levels of harm sonar causes to all whales and dolphins. 

This significant scientific development means that the Navy and NMFS will have to prepare supplemental Environmental Impact Statements pursuant to the National Environmental Policy Act – our nation’s bedrock environmental law – and that NMFS should modify its authorizations that allow the Navy to harm marine mammals when training pursuant to the Marine Mammal Protection Act.  In a letter sent to the Navy and NMFS today, we have asked them to take these steps, recognizing that they have underestimated the harm sonar has on marine mammals.

If the Navy and NMFS take these steps, they will be catching up with what we and the scientific community have known all along.  NRDC has repeatedly pointed to evidence showing harm to beaked whales and other marine mammals at exposure levels much lower than the levels used by the regulators to assess impacts.  The Navy and NMFS have repeatedly disregarded this evidence, which is solid and accepted in the scientific community, arguing that it does not fit into the straightjacket assessment methodology they created (i.e., “That evidence is all well and good, but because it is shaped like a circle and not a square we can’t fit it into our model and are going to ignore it.”).  But this new evidence does fit into their model and they cannot escape its meaning:  as we have repeatedly argued and science has shown, the Navy and NMFS have been underestimating the impact Navy sonar has on whales and dolphins.