Quantifying benefits and impacts of fishing exclusion zones around Marine Renewable Energy Installations

Lead Research Organisation: Marine Biological Association of the United Kingdom
Department Name: Marine Biology

Abstract

Tidal, wave and offshore wind resources will be important for meeting an increasing proportion of society's future energy needs. However, marine renewable energy devices are likely to have direct impacts and indirect effects on shelf and coastal environments and biota across a range of spatio-temporal scales. These potential effects (both positive and negative) have implications for pelagic, demersal and benthic fish and invertebrate (shellfish) populations, their essential habitats and the fisheries they support. Globally, there is at present a very limited understanding of how large-scale development of marine renewable energy installations (MREI) will affect fish and shellfish populations and the fisheries that exploit them.

Whilst some research to date has considered fish sensory responses to probable noise and electromagnetic fields associated with MREIs, the major gaps in knowledge that will have particular socio-economic importance lie in understanding the longer term behavioural and ecological responses, including habitat use by fish and shellfish, arising from marine renewable devices themselves and the areas immediately surrounding areas that exclude fishing. Hence, there is a need to quantify whether fisheries in areas adjacent to fishery exclusion zones around MREI sites in temperate regions are enhanced by the hypothesised biological 'spillover' effect, how MREI areas may be connected biologically, and the biological and socio-economic effects of displacing exploitation pressure from MREI sites to adjacent areas.

In the proposed research we will use a novel combination of behavioural tracking, density estimations and modelling approaches to address whether 'spillover' of species abundance (fish, shellfish) as a consequence of the no-fishing area around MREIs enhance adjacent areas. We propose to conduct research at a small-spatial scale, wave energy test site (the Wave Hub, off Hayle, Cornwall) and a Round 1 (R1) 30-turbine offshore wind farm (North Hoyle, off Rhyl, North Wales) and the area north of this towards the R2 Gwynt-y-Mor wind farm currently under construction. Our approach in these locations will be to quantify where large numbers of fish and shellfish of several species (e.g. edible crab, lobster, Atlantic cod, thornback ray) are located in relation to MREI, adjacent and more distant areas, and how much time they spend in those locations over annual cycles. We will then use this precise spatial information for several hundred individuals to scale up to potential population levels using relative abundance data from surveys for these focal species in those areas. From this, empirical estimates of the magnitude of spillover and its spatio-temporal dynamics will be made. These will be compared with spatial fishery models, to assess how rates of exchange of animals between areas accessible and inaccessible to fishing determine outcomes in terms of both spawning potential and fishery yield. We will use an individual-based modelling approach to identify how patterns of space use by fish/shellfish determine these outcomes when MREIs are introduced into stock areas. This research will also undertake a socio-economic analysis of the impacts and benefits to fisheries of MREIs that exclude fishing, and the effects of displacement of fishing exploitation to adjacent areas.

These data will be contextualised with the relative abundance of predators of fish (seabirds, marine mammals) in MREI and adjacent areas together with how fish and shellfish movements and space use change in response to variations in the physical environment (wave height, current velocity) will allow a deeper understanding of the drivers of distributional change in target species in MREI and adjacent areas. The proposed research will benefit from using novel tracking technologies, including an acoustic monitoring array that is unique to the UK, to obtain the first long-term movement data for multiple species around MREI sites.

Planned Impact

QBEX will investigate key questions relating to how fish and shellfish respond in the longer term to Marine Renewable Energy Installations (MREIs) that exclude fishing and how this affects marine animal abundance in different areas and the fisheries that exploit them. This research will have impact in two very different industries, namely marine renewable energy developers and commercial fisheries, together with the organisations that support and regulate their activities. QBEX will engage directly with numerous stakeholders when considering marine renewables and fisheries, including policy makers such as Defra, Scottish Government and DECC, regulators (MMO and Marine Scotland), fishery managers (IFCAs, Regional Advisory Councils), statutory conservation agencies (CCW, Natural England), and various conservation NGOs (e.g. Wildlife Trusts).

The formation of a science advisory board for the project, comprising the most relevant stakeholders such as Defra, MMO/Welsh Area Government (Fisheries), CCW and Natural England, will ensure QBEX results will be rapidly available. It will also give the opportunity for stakeholders to provide suggestions regarding focus and advise on how best the research could be best disseminated across other stakeholders.

Our participation in a Fisheries and Energy forum via the NERC KE programme will allow particular in-depth discussions with senior officers of fish producers' organisations (e.g. NFFO), regulators such as the MMO, WAG, and executive agencies such as Cefas, enabling dissemination of QBEX research for uptake by policy makers. Frequent and long-term interaction with commercial and recreational fishers at the grass roots level will also be enabled through our operation of a tag reward scheme and during the course of our socio-economic objectives. This will provide the opportunity to convey our research ideas and results directly to individual fishers whi may be affected by MREIs.

Engagement with energy developers (e.g. Npower, Dong Energy) and environmental consultants (e.g. CMACS Ltd) will also occur through discussions about our research objectives and what they can deliver in terms of an understanding of potential benefits as well as impacts to fish ecology and fisheries around MREIs. This engagement will be most detailed with those developers we have already approached with respect to QBEX undertaking research within and around their MREIs.
 
Description (1) The long-term monitoring of fish spatial movements around Marine Renewable Energy Installations (MREIs) has been determined through new electronic tagging of fish and novel track reconstruction using the enhanced tidal Geolocation Hidden Markov Model (HMM). This has provided a world-leading capability for determining the most highly spatially resolved movement tracks of bottom-dwelling fish. This new capability enables new insights into how fish use marine areas impacted by offshore wind farms.

(2) Track reconstructions from archival tags showing long-term movements (up to 3 years) of electro-sensitive thornback rays identify overlap with multiple MREIs in the Irish Sea. Overall eight consented MREI sites were visited by rays at some time however on average they only spent 7% of their time annually within MREI sites. Most spatial overlap occurred during summer months when thornbacks were on feeding grounds, with less overlap during winter when adult females migrated to deep water habitats. Importantly, tags show that when migrating rays swim well above the seabed making interruption of migration routes by seabed electric cables less likely than previously supposed. Overall results show that fishing exclusion zones (de facto partial-no take Marine Protected Areas, MPAs) provide fish with minimal and transient protection from fishing pressure occurring outside impacted areas.

(3) Fishing vessel movements and landings from areas visited demonstrate offshore wind farms have affected fishing locations, fisher income arising from those areas, and has led to displacement to adjacent fishing grounds. Fishing activity was calculated before, during and in most cases after construction of 19 offshore wind farm sites around the UK. Results show that for a few wind farm sites a significant amount of fishing effort was disrupted, particularly for those in the Irish Sea. In these cases there was a noticeable loss of fishing activity (and associated landings) once the wind farms were constructed. For example, the Walney 1 wind farm in the western Irish Sea supported annual fish landings with avergae value of £3,931, which reduced to zero following wind farm construction. Spatial hotspot analysis was undertaken and inferred that effort was likely displaced to nearby productive fishing grounds.
Exploitation Route These data may be used by stakeholders such as the Marine Management Organisation to determine the impact of offshore wind farms on fisheries. In addition these findings will underpin testing of the European Marine Strategy Framework aim of an ecologically coherent network of marine protected areas.
Sectors Agriculture, Food and Drink,Energy,Environment

 
Title Development of enhanced tidal geolocation model for reconstructing marine fish movements and migration from archival-tag depth data 
Description Significant progress has been made in developing and validating using static depth data a new enhanced tidal geolocation model that will improve the accuracy with which marine fish locations can be estimated. The model testing has proved successful. 
Type Of Material Computer model/algorithm 
Provided To Others? No  
Impact This model will allow demersal fish movements to be reconstructed accurately at high spatial resolution for the first time, with potential applications to all continental shelf seas. 
 
Title Development, testing and full implementation of enhanced Tidal Geolocation Hidden Markov Model for fish tracking 
Description The model enables geolocation of bottom-dwelling tagged fish by matching the tidal patterns recorded by the pressure-sensitive tag to tidal signals within a spatially explicit tidal model. The hidden Markov model (HMM) for tidal geolocation used in this study was an extension of that presented by Pedersen et al. (2008), which uses the detectable tidal patterns recorded in fish-tag depth records to partition the movements of a fish into two activity states, each having separate movement parameters that are estimated by maximum likelihood. The probabilistic method estimates the most probable track of the fish. The accuracy and reliability of the predicted tidal locations were verified by geolocating time series of depth records from stationary tags moored to the seafloor at known locations. The Marine Biological Association (MBA) has developed, tested and implemented novel improvements to the original model, enhancing its accuracy for resolving long-term fish movements. 
Type Of Material Computer model/algorithm 
Year Produced 2014 
Provided To Others? Yes  
Impact Novel improvements to an existing Tidal Geolocation Hidden Markov Model (HMM) for tracking bottom-dwelling fish with higher accuracy than previously possible have been implemented by the Marine Biological Association (MBA) and validated using moored tag data. Spatial accuracies between actual and estimated positions of < 1 km on average were achieved, indicating that the new method improves spatial accuracy by an order of magnitude compared to the original HMM. This new model capability enabled the first determination of how long commercially important fish may remain within Marine Renewable Energy installations (MREI). MBA has used the new improvements to the tidal geolocation HMM to complete the analysis of all the thornback ray data storage tag (DST) returns (n=30) from the southern Irish Sea and to assess overlap with offshore wind farms in the region. Results show rays spent only 7% of track days within MREIs indicating that as fishing exclusion zones (de factor partial take Marine Protected Areas, MPAs) they provide minimal and transient protection to fish from fishing pressure occurring outside impacted areas. 
 
Title Novel analysis to determine cost to fisheries of offshore wind farm construction 
Description A novel database of fishing vessel spatial movements and distributions through time (2007-2013) and the fish landings from those locations in relation to offshore wind farm sites before during and after construction. The database was assembled from source data obtained under license from the Marine Management Organisation (MMO). 
Type Of Material Data analysis technique 
Year Produced 2015 
Provided To Others? Yes  
Impact The Marine Biological Association (MBA) used the database of fishing vessel movements to demonstrate how offshore wind farms before, during and after construction have affected fishing locations and the value of catches made in those areas. The database was prepared for analysis after correction of errors in the source database provided by the MMO. Fishing activity was calculated before, during and in most cases after construction of 19 offshore wind farm sites around the UK. Results show that for a few wind farm sites a significant amount of fishing effort was disrupted, particularly for those in the southern Irish Sea. For these there was a noticeable loss of fishing activity (and associated landings) once the windfarms were constructed. For example, the Walney 1 wind farm in the western Irish Sea supported annual fish landings valued at £3,931 on average, which reduced to zero following wind farm construction. Spatial hotspot analysis was undertaken and inferred that effort was likely displaced to nearby productive fishing grounds. 
 
Description Development of enhanced tidal geolocation model for reconstructing marine fish movements and migration from archival-tag depth data 
Organisation National Oceanography Centre
Country United Kingdom 
Sector Academic/University 
PI Contribution The MBA have collaborated with the National Oceanography Centre Liverpool in this work.
Start Year 2012