The mass stranding event (MSE) in Cornwall UK last year points to Navy sonar. But if you read through the very comprehensive report you can see why it is difficult to arrive at unimpeachable scientific conclusions.
The report is here:
http://randd.defra.gov.uk/Document.aspx?Document=WC0601_8031_TRP.pdf
The quote from the report conclusion states:
“A period of naval exercises involving a variety of high intensity acoustic sources were conducted around the time of the MSE, but evidence of one of more specific naval activities that tightly coincided in time and space with the likely initial onset of the MSE were absent in all the records of naval activities released under the Freedom of Information Act.”
The term “tightly coincided in time” is at issue because the exercises were conducted within 60 hours of the strandings – close enough to not be eliminated as a cause, but not so close as to indicate sonar as a definitive reason for the stranding.
The report is quite thorough and illustrates why it is so difficult to ascertain causation for any stranding event.
This illustrates why the US Navy can state with scientific certainty that “only 37 whales have stranded as a consequence of Navy sonar.”
In science there is no Racketeer Influenced and Corrupt Organizations (RICO) act that can indict criminals because they always seem to be around the scene of a crime. We can only look at the correlations and make our informed assumptions.