To the Editor:
In response to the June 24, 2017 piece, “Block Island Wind Farm May Have Killed Young Humpback Whale,” several of us, researchers at the University of Rhode Island (URI), feel it is important to explain from a scientific view why it is highly unlikely the whale’s death had anything at all to do with a turbine from the Block Island Wind Farm. Since 2007, when we undertook significant studies, through the rigorous Rhode Island Ocean Special Area Management Plan (Ocean SAMP) process, to understand how wind farms could impact ocean animals, including whales, we have learned a great deal about what does, and doesn’t, pose threats to them. This information has been widely shared through the years, and we’re pleased to share it once more. Here are some key facts, from both biological science and acoustical science perspectives – both integral to understanding how human technology interacts with marine animals – and we’re sharing several peer-reviewed, academic papers at the end of this, should people want to read more extensively:
1) Low Wind Farm Noise: The noise from the Block Island Wind Farm wind turbines has been measured at about 100 underwater decibels (dB) at a range of about 50 meters. This is very low and only detectable when ships are not nearby and when the wind is not too strong.
2) Construction is Long Past: Pile driving occurred in August, September and October of 2015 for the wind farm and is almost certainly not the cause of the recent strandings of humpback whales.
3) Whales Themselves are Louder than Turbines: The source levels of social calls of humpback whales have been measured to be 123 to 183 underwater dB at 1 meter. Scientists have measured fin whale vocalizations near the Block Island Wind Farm at more than 140 underwater dB at a range of 500 meters and this agrees with published work that shows the source level of fin whales to be more than 180 underwater dB.
Much of the information in the June 24 article is wrong or inaccurate; we do not find it helpful to reemphasize these inaccuracies, but it’s worth noting a few general, widely known points useful for the public. For example, neither Humpback nor Minke whales use echolocation (sonar) at all, and Minkes do not live in “families” and are, essentially, not social. Also, the humpback Unusual Mortality Event (UME) started over a year ago, so this should have specified “since January 2016,” rather than compressing the mortalities from 18 months to 6 and tripling the apparent rate. And finally, the average number of humpback strandings per year before this death or UME, and before there were any wind turbines in operation along the East Coast, was about 11.
Thank you for sharing this information with your readers – it’s important that people care for ocean animals and other issues, but they need the best available science in order to do so.
Sincerely,
Bob Kenney, Ph.D, Emeritus Marine Research Scientist, URI Graduate School of Oceanography (rkenney@uri.edu)
Jim Miller, Sc.D, Professor of Ocean Engineering and Oceanography, University of Rhode Island (miller@uri.edu)
Sources:
http://asa.scitation.org/doi/10.1121/1.4807828
http://asa.scitation.org/doi/10.1121/1.4988927
http://asa.scitation.org/doi/10.1121/1.4989144
http://www.nmfs.noaa.gov/pr/health/mmume/2017humpbackatlanticume.html
