New York State
Environmental Technical Working Group
Whale Communications Committee
Whale Communications Committee
The Offshore Wind Environmental Technical Working Group (E-TWG) formed a specialist committee in 2023 to develop communications materials to aid in the dissemination of accurate, readily understandable information around recent whale mortality events and the level of potential risk to whales from offshore wind energy development activities.
This committee is developing a series of Frequently Asked Questions (FAQs) as a resource for stakeholders who are in direct communication with the general public and receive questions related to whales and offshore wind. The intent of this effort is to provide scientifically sound, accurate answers to address common questions. Given the urgency of disseminating accurate information, this FAQ resource will be updated over time to address emerging questions related to whales and offshore wind energy development.
Brief responses to FAQs are summarized on this page below, with additional detailed responses and graphics in the FAQ document.
Please fill out this survey to provide input on the topics that the committee should cover and/or indicate your willingness to provide your expertise in draft product development. For additional information on the whale communications committee or other E-TWG activities, please contact Julia Gulka.
Frequently Asked Questions
Strandings and Unusual Mortality Events
What are strandings and unusual mortality events?
Whales and other cetaceans (such as dolphins and porpoises) are considered stranded when they are found on the shore (dead or alive), when they are found dead at sea (e.g., if the body is floating in the water), or when found alive at sea but unable to return to their natural habitat (e.g., if trapped in shallow water or injured). As defined in the U.S. Marine Mammal Protection Act, an unusual mortality event (UME) is “a stranding that is unexpected; involves a significant die-off of any marine mammal population; and demands immediate response.” A UME can occur over multiple years and across regions and may affect a single species or various species. Individuals or groups of animals can strand, depending on the species and situation. For more detailed information and scientific citations, please see the full FAQ document.
What are some of the causes of stranding events for marine mammals?
Strandings are often caused by 1) injuries due to vessel collisions, entanglement or ingestion of active and derelict fishing gear and marine debris, or other human interactions; 2) infectious and non-infectious diseases; 3) malnutrition; 4) unusual weather events or oceanographic conditions; or 5) some combination of these or other factors. Climate change has altered the migration and distribution of whale species and their prey and, in some cases, increased their interaction with vessels and other anthropogenic activities. Climate change also has the potential to contribute to changed patterns of pathogen emergence, distribution, abundance, and transmission, all of which can lead to increased strandings. For more detailed information and scientific citations, please see the full FAQ document.
Why are baleen whales dying in the Northwest Atlantic and is this a new phenomenon?
Generally, existing evidence suggests that the main anthropogenic causes of death for baleen whales are vessel strike and entanglement in fishing gear. However, the cause varies by species. While we lack information for many whale mortalities (e.g., those that aren’t detected or necropsied, or for which cause of death cannot be determined; see What are the biases and limitations of stranding data?), data suggest that the greatest risk to humpback whales is vessel collisions (50% of necropsies showed evidence of vessel interaction), whereas 65% of North Atlantic right whales that have been killed or injured were entangled in fishing gear. Recent increases in the number of baleen whale deaths in the Northwest Atlantic region relate to a combination of natural and anthropogenic factors. These include increases in population size 6 (humpback whales), shifting prey and whale distributions inshore, infectious disease, and changes in the locations and amount of shipping activity, leading to increased interactions with vessels. For more detailed information and scientific citations, please see the full FAQ document.
What can we learn from stranding data?
Strandings can provide important information on disease, health, and causes of death. Stranding data are especially important for learning about susceptible and rare populations/species. Stranding and entanglement networks fill a valuable bio-surveillance role, as they are often the first to detect threats to marine mammal populations. For more detailed information and scientific citations, please see the full FAQ document.
What are the biases or limitations of stranding data?
Detecting strandings and determining their causes is challenging. Many factors influence stranding occurrences and rates. This means it is difficult to understand whether observed changes in the timing, location, or rate of strandings reflect changes in actual mortality in a population. Availability of stranding data depends on the strandings being detected by people (e.g., some animals never wash ashore), knowledge of how to report the stranding, and stranding network partners that are able to further investigate an event when it detected and reported. For more detailed information and scientific citations, please see the full FAQ document.
How are necropsies conducted?
Similar to an autopsy in humans, a necropsy is the examination of a deceased animal to identify cause of death and collect other information on the health of the individual, the species, and the marine environment. In the United States, whale necropsies are conducted by organizations that are members of the National Marine Mammal Stranding Response Network. All reported strandings are documented, but it is not possible to conduct necropsies in many cases due to human safety, the state of carcass decomposition, stranding location, or other reasons. Necropsies can provide valuable information but cause of death cannot always be determined. Complicating factors include the level of decomposition, inability to collect or process samples due to limited accessibility or resources, inconclusive test results, and difficulty identifying multiple factors that may contribute to the cause of death. For more detailed information and scientific citations, please see the full FAQ document.
Offshore Wind Development Process
What are the major components of an offshore wind farm?
Offshore wind farms are typically comprised of turbines, whose rotors convert mechanical energy from wind into electrical energy, and an offshore substation, which are linked to each other by a network of electrical cables. The electricity is transported onshore via export cables (which are typically buried in the seafloor) so that the energy can be integrated into the electrical grid. Turbines can either have fixed foundations, in which the foundation is driven into the seabed, or floating foundations, which have a series of anchors attached to the foundation via mooring lines. Floating turbine designs are newer and are generally deployed in much deeper waters (50-300 m, or 164-984 ft). For more detailed information and scientific citations, please see the full FAQ document.
What are the potential effects of offshore wind development on whales?
The primary factors associated with offshore wind development that may affect whales include underwater sound, vessel activities, and habitat change. Offshore wind development introduces a variety of sounds into the environment, particularly during wind farm construction, as well as additional boat traffic during construction, operations, and maintenance activities. In addition, offshore wind development could lead to changes in the habitats, which may result in either positive (e.g., creating of artificial reefs) or negative change (e.g., effective habitat loss). The potential impacts to individuals and populations from each of these changes will depend on multiple factors, including behavior, life history, population size, and habitat use. For more detailed information and scientific citations, please see the full FAQ document.
Does offshore wind energy development kill whales?
There is no documented scientific evidence that offshore wind energy activities kill whales. While offshore wind energy development, like any marine development, has the potential to affect whales (see What are the potential effects of offshore wind development on whales?), the sounds produced during all phases (i.e., site assessment, construction, and operations) are insufficient to cause direct mortality. However, the sound emitted may impact hearing or behavior, and cumulation of sounds from anthropogenic sources may lead to chronic effects. There are various mitigation measures in place to reduce risk of potential impacts (see What mitigation measures are being required by regulators in the U.S. for offshore wind?) Collisions are a concern for all vessels in the marine environment across industries. Vessel collisions have the potential to injure or kill whales. However, offshore wind vessels comprise a very small portion of all vessels in the marine environment, and they operate in a more precautionary manner to avoid the types of collisions that occur with other industries, which reduces this risk (see What mitigation measures are being required by regulators in the U.S. for offshore wind?). For more detailed information and scientific citations, please see the full FAQ document.
Offshore Wind Regulatory Processes and Mitigation
What federal and international environmental laws protect whales?
The Marine Mammal Protection Act (MMPA), Endangered Species Act (ESA), and National Environmental Policy Act (NEPA) protect marine mammals in United States waters. The International Whaling Commission (IWC) and the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) also regulate human activities around marine mammals and endangered species. During the OSW development process, the Bureau of Ocean Energy Management (BOEM) oversees multi-year, multi-step regulatory processes mandated under NEPA, the MMPA, and the ESA. Some number of “incidental takes” of marine mammals may be permitted during the offshore wind development process; take means that there is a disturbance of a marine mammal, however minor in scale. Offshore wind companies are not issued permits for take in which an animal is killed or injured beyond the point of recovery. For more detailed information and scientific citations, please see the full FAQ document.
What mitigation measures are available to avoid or minimize OSW effects on marine mammals?
There are a range of mitigation approaches that are used by the offshore wind industry and/or other industries in various regions to help avoid and minimize potential effects to marine mammals from sound and vessel collisions. Mitigations generally fall into three categories: approaches to reduce the likelihood of marine mammal presence in an area when sound-generating activities occur, reduce the sound that is emitted into the environment, or mitigate risk of vessel strikes. The effectiveness of mitigation measures depends on many factors including species, specifications/implementation, and compliance. The mitigation plan for each offshore wind project is informed by the species within the area, the geographic and environmental features of the area (such as seabed sediment type, which can influence options for turbine foundations), and the cost of the mitigation measure and is defined by federal agencies (Bureau of Ocean Energy Management (BOEM), NOAA Fisheries), with additional approval by the International Maritime Organization required for vessel-related mitigation. Increasing our environmental, biological, and technical knowledge can lead to better decision-making and implementation of various mitigation techniques. For more detailed information and scientific citations, please see the full FAQ document.
What mitigation measures are being required by regulators in the U.S. for offshore wind?
The details of requirements for specific offshore wind projects varies based on permit requirements from the Bureau of Ocean Energy Management (BOEM) and can be found in various permitting documents including the Construction and Operations Plan Approval and the Record of Decision. In general, these requirements relate to reducing collision risk from vessels and impacts from sound during construction. To reduce vessel-related impacts, requirements generally include vessel speed restrictions (10 knots or less during certain periods of the year) and dedicated observers on vessels (when traveling above 10 knots). Generally, requirements related to reducing sound-related impacts during construction activities include temporal restrictions on pile-driving activities, mitigation measures during pile driving (e.g., Protected Species Observers and passive acoustic monitoring), ramp-up/soft start during sound-generating activities, and use of sound abatement systems (e.g., bubble curtains) during pile driving. Offshore wind mitigation and monitoring requirements are much more stringent than those for other maritime industries such as shipping. For more detailed information and scientific citations, please see the full FAQ document.
Other Resources
There are a variety of science communications materials and science-based information available on wildlife and offshore wind energy development. In addition to the webinar library, a selection of resources are available here.
Photo credits: Humpback whale © Thomas Kelley - Unsplash; Whales spout © Ryan Stone- Unsplash; Wind farm © David Will - pixabay;