Is Offshore Wind Killing Whales?
In the quest for cleaner energy, the United States government and government-sponsored companies are reviving the offshore wind farm - a technology like land wind turbines that could help us fight climate change. But new evidence suggests that the effects of offshore wind may be a bit more complicated than we thought.

This winter, until the time of this post, at least 16 whales have met a tragic end on the shores of the United States east coast. But what had killed them? Alarmed, Republican Congressmen Van Drew and Harris issued a statement calling for temporary termination of all offshore wind projects until environmental regulation agencies could determine whether such projects were in fact what killed the whales. New Jersey in general is quite upset, with 30 mayors telling Congress to halt offshore wind projects and an NJ congressman issuing a bill demanding investigation into environmental review processes regarding offshore wind. But do the concerns of these people have any merit?
According to the nonprofit Clean Ocean Action, yes. Just this month, Clean Ocean Action issued a memorandum to be reviewed by the district court of Massachusetts indicating their concern about the failure of federal agencies Bureau of Ocean and Energy Management (BOEM), the National Marine Fisheries Service (NMFS), and the
Army Corps of Engineers (ACE) to properly evaluate the potential effects of offshore wind farms on marine life. According to Clean Ocean Action's report, offshore wind technology "...inarguably damages and eliminates vast areas of marine habitat and available fishing grounds, generates underwater noise, increases vessel traffic, emits air pollutants, and creates obstacles to vessel navigation and marine life migration. Accordingly, OSW [offshore wind farms] has the potential to profoundly impact marine life, including from increased vessel strikes, disruption of feeding, breeding and migratory patterns, and alterations of the food web." In other words, offshore wind is destructive to marine life, from apparently whales to cod fish, birds, and even seamount ecosystems. Given the number of offshore wind projects destined for east coast shores, this is certainly cause for concern.
But wait, what is "offshore wind", and why the uproar all of the sudden? Well, offshore wind is like onshore wind - big wind turbines whose gigantic blades, by turning in the wind, generate electricity, only offshore windmills are, well, in the sea, and much bigger and beefier. Like onshore windmills, they rely on the renewable energy of wind and therefore are supposedly cleaner than oil and gas and thus better for the climate. They also generate more power than onshore wind. You can learn more about how wind turbines work here.

Offshore wind farm. Source: Rosen, 2016.
Offshore wind has been around for a few decades now. However, starting in 2015-16, NOAA began authorizing what are called Incidental Take Authorizations, or ITAs (also called IHAs). These are reports that authorize the accidental "taking", or "harassment", of a certain number of sea creatures during operations (that is, they allow certain levels of death and distress). Some of the operations of installing an offshore wind farm include surveys of potential sites that utilize loud sonar noises to see if the sites are fit for farms, and each one can last a whole year. Whales are sensitive to these sounds, which can cause behavioral changes and physical injury. Unlike onshore turbines, offshore turbines are directly driven into the seabed using a type of foundation known as a "monopile". This process is called "pile driving" and creates sounds that can be highly disruptive and even damaging to marine animals like whales. (Do note, however, that monopiles are not the only method of anchoring offshore turbines - there are other foundations, but monopiles are the most commonly used.) Part of the surveys includes assessing ship traffic routes, and farms are installed where there is light traffic, understandably. Also understandably, whales will want to avoid these loud sounds. They end up going where the heavy traffic is, possibly resulting in collisions. The construction and decommissioning processes for offshore turbines also include methods that are damaging to marine environments, like dredging (here, here, and here) and cable-laying.
Not only can offshore wind damage marine life and ecosystems, the process of mining and making the turbines is also incredibly unjust on land, both environmentally and for humans. The magnets, batteries, and other parts used in the turbines and to run them require greater amounts of rare earth elements and critical minerals than any other energy technology. These minerals are mined from places like China and the Congo, which use forced, slave, or child labor. The mining process also produces large amounts of air and water pollution.
A closer look at the data reveals something interesting. The advent of ITAs in 2016 strongly corresponds with major unusual mortality events (mass die-offs, UMEs for short) of humpback whales and Minke whales that also started in 2016 and 2017, respectively; and continue to this day. Sperm whales and North Atlantic right whales (NARW), a critically endangered species, also seem to be affected by the noise of offshore wind. One goal of the ITAs is to evaluate for the potential impact of offshore activity on marine life and allow for only a few accidental deaths from such activity. However, authorizations may be allowing for much higher numbers of deaths and damages - including one authorization permitting damage to nearly a third of the NARW population and NOAA in general allowing the killing of over 2 right whales per year, well above the limit.
In response to these growing concerns, NOAA claims the whale deaths are not from offshore wind, but from ship collisions and entanglement in nets. This may be true, but as stated above, those collisions could be happening because the whales are trying to avoid the offshore activity, although this cannot be said for certain. NOAA also claims the rise in humpback whale deaths is due to a rise in population, and denies any links between whale deaths and offshore wind surveys. Also, BOEM claims to have "adequately assessed" the environmental impact of a government-backed offshore wind project on Virginia seas, and has regulations in place for mitigating damage to sea life from offshore wind throughout the construction process, from survey to functioning farm. If you remember, BOEM is one of the federal agencies Clean Ocean Action accused of failing to properly evaluate the environmental impact of Vineyard Wind, another offshore wind project. Vineyard Wind itself partnered with several other conservation NGOs to form a risk-mitigation agreement to ensure offshore wind does not cause significant environmental harm. (This article by the Marine Mammal Commission also outlines the risks of offshore wind/hydrokinetic power to marine life and precautions being taken by BOEM to mitigate damage.)
Maybe BOEM and NOAA have done their proper research, but given the evidence described above, the verdict seems a little premature, and there may be benefit to suspending the projects at least until more data is gathered. However, there is also reason to suspect that BOEM's assessments and regulations for offshore wind projects in general are inadequate and not holding wind technology to the same standards as fossil fuel technology. Moreover, BOEM and NOAA both issued statements (here and here) acknowledging the damage offshore wind could do to marine life, especially whales, including how it could disrupt right whale food sources, increase vessel strikes via avoidance, and more. This is despite a NOAA report about a study attributing the deaths of 40% of about 89 whales (of 178 total since 2016) to collisions and entanglements with no clear cause. Their conclusion from this study is that offshore wind is definitely not the cause of the 2016-2023 UME. The study was apparently conducted by the Marine Mammal Commission, but I have not been able to find the paper itself, only the report from NOAA.
Based on the NOAA study alone, it would appear that offshore wind noise is not a significant cause of the recent UME. In fact, the conclusion is not that far-fetched, as noise from offshore wind activity is not as loud and disruptive as noise from offshore drilling/oil, military sonar, and industrial shipping. Even so, there have been concerns about the noise still being at least somewhat disruptive; if that is the case, then offshore wind could still indirectly be contributing to the whale deaths by leading them to strikes and entanglements as explained above. Regarding right whales, NOAA may be on to something regarding the entanglements - although the necropsies were done on humpback whales, Maine lobster was pulled from stores due to the threat its fishing methods pose to NARWs.
Humpback whales, North Atlantic Right whales, and Sperm whales are some of the marine mammal species reported in the 2016-2023 UME. Sources: Humpback whale from Unsplash; Right whale from Sharkey, n.d.; Sperm whale from Yahoo.com; Minke whale from Contreras, 2015.
One interesting thing to note, however, is that the UK has even more fully-functioning offshore wind farms than the US does, and that also in the UK, strandings of all sorts of species have been on the rise since 2010-11 (also here). Autopsies of the bodies concluded various causes, from entanglements to infection to trauma (e.g. from collisions). Many of the species in both the US and UK strandings have ranges that include UK shores. However, the migration routes of the US species do not cross UK seas; neither are any major breeding or feeding areas found around the UK, at least for humpback whales (the data are scant for sperm whales and NARWs species). The United States east coast, however, is a hot spot for humpback whale feeding and part of the NARW migration routes, where significant offshore wind activity is happening (see a map of whale migrations routes here). For comparison, this is where US (as of 2021) and UK (as of 2020) offshore wind projects are running or planned, and this is a timeline of major offshore wind projects in the UK from 2000-2021. Another curiosity in the situation lies in the unusually high percentage of complaints against offshore wind for hurting whales originating from New Jersey sources; specifically, organizations like Protect Our Coast NJ. These organizations appear to be independent, grassroots-led, non-partisan, and genuinely concerned for the environment at first, but deeper digging reveals their connection to the Caesar Rodney Institute, which is funded by the oil industry.
It's important to note that correlation does not equal causation. At this point, the coincidence of an almost anomalously significant uptick in whale deaths occurring on the US east coast during the same time frame preparation for and building of offshore wind farms is happening warrants greater investigation. Complicating the acquisition of data is the possibility that many more whales may be dying out at sea than we know of, where their corpses are inaccessible for study. Overall, however, there is a lack of solid, direct evidence indicating an effect of offshore wind on whales one way or the other, and thus we cannot conclusively say that offshore wind is or is not harming and killing whales. We also need to be aware that while the evidence connecting offshore wind to whale mortality is currently inconclusive at best, offshore oil drilling is known to interfere with the whales' well-being and harm many other species and ecosystems; not to mention the general pollution it causes and that, unlike offshore wind, offshore drilling has the risk of oil spills.
The aforementioned Virginia project is part of a greater effort by the Biden administration in 2021 to jump-start American offshore wind technology. Biden plans on expanding the projects to farms all around the nation's coasts to meet 2030 clean energy goals. This is a noble goal, and if done right, renewable energy can be a great way to help relieve our environmental woes, at least until we develop better technology like nuclear fusion. However, we also need to understand that climate change is merely a symptom of a greater problem: the destruction of life on Earth. That life is also the reason we care about climate change in the first place, so whatever methods we use to mitigate climate change - whether it be wind power, solar power, fossil fuels, nuclear, or something else - we need to make sure those methods do not destroy the very lives we seek to save by our efforts. In order to ensure the safety of species and ecosystems while we build our new energy technologies, it's worth holding off just a little bit until we can be more confident that our technologies aren't hurting them.
If you're interested in more information, you can follow the links below:
IHAs
List of companies that signed statement by American Coalition for Ocean Protection, which is funded by the Caesar Rodney Institute
Big Oil also has a stake in offshore wind (also here and here). Also note that some companies (not necessarily oil) use a deceptive practice called greenwashing, in which they sell "green" products or efforts to customers, when behind the scenes they are not at all improving their sustainability practices (and here are some recent examples of greenwashing). I am not saying that Big Oil is guilty of this with offshore wind, but it's something to be aware of.