Abstract
The following report summarizes the findings of a project centered on gathering input on the potential impacts to fisheries resources from offshore wind energy development in three Wind Energy Areas as defined in Table 1 off the coasts of Rhode Island, Massachusetts, New York and New Jersey, and the best methods for evaluating potential impacts. It is important to note that “Wind Energy Area” and the acronym “WEA” used in this report refer specifically to areas as they are defined in Table 1 and do not reflect definitions used by BOEM in differentiating a particular phase of pre or post lease issuance. The Bureau of Ocean Energy Management (BOEM) has issued a total of four leases to two companies in two of the WEAs and is currently gathering information on the Cholera Bank WEA described in this report. Over the course of several months, input was received from members of the commercial fishing industry, fisheries managers, and marine scientists based in the northeast United States through small group discussions, written responses, e-mail correspondence, and phone interviews. The purpose of the project was to assist BOEM as it develops regulations and guidelines for offshore wind energy developers regarding research and monitoring requirements. The major project findings include the following:
- Currently, the site specific project data needed to evaluate the potential impacts on fisheries resources in these WEAs is lacking, resulting in uncertainty and speculation;
- Given what is known about the fisheries resources in these areas, there is general agreement that there will be impacts, but the types of impacts and their significance is uncertain;
- Robust baseline research and ongoing monitoring utilizing a variety of approaches will be needed to evaluate impacts and determine mitigation measures;
- Identification of impacts directly attributable to offshore wind energy development activities may be challenging given changes caused by other factors such as climate change, ecosystem dynamics, fishing pressure, and natural interannual variability;
- Guidance on recommended standard assessment protocols is lacking from existing offshore wind energy development projects;
- In assessing impacts, attention will need to be focused on species that are commercially or ecologically important, have undergone or are in the process of rebuilding, or are designated as protected or endangered.
In discussing how individual fish and invertebrate species might be impacted by offshore wind energy development, project participants provided the following major points: 1) The species or species groups present in these WEAs, likely to be impacted by development activities, and therefore important to target in research and monitoring efforts include: alewife, American lobster, Atlantic cod, Atlantic herring, Atlantic sturgeon, black sea bass, blueback herring, bluefish, blue mussels, butterfish, haddock, Jonah crabs, little/winter skates, longfin squid, mackerels, mako shark, menhaden, monkfish, ocean quahogs, pollock, red hake, sea scallops, scup, silver hake, spiny dogfish, striped bass, summer flounder, surf clams, thresher shark, tunas, winter flounder, and yellowtail flounder; 2) Habitat changes associated with offshore wind energy facility construction and operation , such as loss of hard bottom and sand wave habitats due to sedimentation and scouring, addition of high - relief habitat around turbines, redistribution/displacement of important spawning, nursery, and foraging habitats, the creation of micro habitats from shading effects, and introduction of novel electromagnetic fields, are likely to impact larval, juvenile, and adult stages of many fish and invertebrate species in a variety of ways; 3) Changes in sea surface and seafloor circulation patterns associated with the development of offshore wind energy facilities could affect patterns of larval drift and settlement, upwelling events and productivity cycles that drive fish production, and sedimentation processes that influence species assemblage structure and trophic interactions; and 4) Increased noise and vibration associated with turbine construction and operation and increased boat traffic could result in increased larval mortality for many fish and invertebrate species, displacement of or interruption to migration patterns and reproductive behaviors, alteration of species distributions, and injury or mortality of fish with swim bladders.
Some respondents emphasized that an adequate understanding of ecosystem structure and trophic relationships on the WEA scale have not yet been developed, but are essential to achieve before moving forward with development activities. Ecosystem-wide changes could potentially stem from the displacement or redistribution of species that play key trophic roles, changes to predator-prey relationships, introduction of invasive species, and alteration of benthic habitats and circulation patterns, among others. Monitoring of indicator species could be a method of tracking ecosystem changes. Concerns were also raised about possible pollution or debris fields resulting from vessel accidents or turbine/pylon damage.
During discussions, some possible mitigation options were mentioned. These included requiring developers to: 1) Avoid placing offshore wind energy structures in critical habitat areas and along migration routes; 2) Constrain the footprint size and construction schedules to minimize disturbance to key species and processes; 3) Reduce potential noise and vibration impacts by utilizing soft start procedures and/or noise abatement measures; and 4) Bury and regularly monitor the burial depth of power cables to minimize exposure to electromagnetic fields.
In terms of a recommended research and monitoring approach to assess impacts, all project participants agreed that it is critically important to conduct adequate baseline survey work in each WEA prior to construction for at least 2-3 years. Pre-baseline research may also be needed to identify critical habitat areas and seasonal species distributions within each WEA in order to develop effective and efficient baseline and monitoring protocols. It is essential that baseline survey work employ methodologies that can be replicated in ongoing monitoring studies once wind energy facilities are constructed and include appropriate control sites, so impacts can be properly assessed. An ideal research program would incorporate the use of different gear types for survey work (otter and beam trawls, pots/traps, fixed nets, and hook and line) and be accompanied by acoustic telemetry, ichthyoplankton sampling, tissue/stomach sampling, visual surveys (habitat cameras), interferometric sonar surveys, and oceanographic observation and modeling (stratification and flow assessments), with data collection occurring during all four seasons.
In general, the input received throughout this project indicated that research questions driving data collection activities need to be clearly identified and agreed upon before development begins. Baseline survey work prior to construction needs to be directed towards developing a more site specific understanding of what species of concern are utilizing these WEAs and how they are dependent on the areas during different times of the year and phases of their life cycles. Ongoing monitoring efforts would be aimed at detecting how development activities alter the environment in the WEAs, and the biological and ecological impacts they produce.
A comprehensive literature review conducted as part of the project indicated that potential impacts of offshore wind energy development on fisheries resources are not well understood, both here in the U.S. and abroad. The multiple phases of development may have varying impacts on the different life history stages of the species present over time. Previous studies indicate the factors that may impact species in these WEAs include: habitat alteration, noise and vibration, electromagnetic fields, scouring and sedimentation, reef effects, introduction of invasive species, lighting effects, ecosystem changes and trophic cascades, and pollution from accidents or structural damage. These factors were also raised in relation to the WEAs discussed by participants in this project.
Regarding the approaches that should be undertaken to assess impacts on fisheries resources from offshore wind energy development, participants highlighted the following major points: 1) The research and monitoring needed should be funded by wind energy developers or wind energy developers and BOEM; 2) Research priority should be given to understanding the significance of WEAs to the reproduction, growth, and survival of species that are commercially or ecologically important, have undergone or are in the process of rebuilding, or are protected or endangered; 3) Data management protocols need to ensure that all resultant data is publicly accessible and available for outside analysis; 4) Pre-baseline studies and planning for baseline survey work should begin immediately for all the WEAs, with actual baseline surveys beginning as soon as possible in the Cox’s Ledge WEA; 5) The identification of information needs, setting of research priorities, and implementation of a comprehensive research program should be approached collaboratively, involving members of the commercial fishing industry, fisheries scientists and managers, offshore wind energy developers, and BOEM; 6) Leadership to facilitate, organize, and administer the development of a comprehensive, coordinated research approach and plan is critically needed.