Lyme Bay - A case study: measuring recovery of benthic species, assessing potential spill-over effects and socio-economic changes

Transcription

1 Lyme Bay - A case study: measuring recovery of benthic species, assessing potential spill-over effects and socio-economic changes Annual Report No 2 Final October 2010

2 Project Title: Lyme Bay - A case study: measuring recovery of benthic species, assessing potential spill-over effects and socio-economic changes Report 2: Annual Report Project Code: MB0101 Marine Biodiversity R&D Programme Defra Contract Manager: Carole Kelly Funded by: Department for Environment Food and Rural Affairs (Defra) Marine and Fisheries Science Unit Marine Directorate Nobel House 17 Smith Square London SW1P 3JR & Natural England Northminster House Peterborough PE1 1UA Authorship: Attrill MJ, Bayley DTI, Gall SC, Hattam C, Jackson EL, Langmead O, Mangi S, Marshall C, Munro C, Rees S, Rodwell L, Sheehan EV, Stevens, TF. Strong S Lyme Bay a case-study: measuring recovery of benthic species; assessing potential spillover effects and socio-economic changes, Annual Report, December Report to the Department of Environment, Food and Rural Affairs from the University of Plymouth-led consortium. Plymouth: University of Plymouth Enterprise Ltd. 53 pages. Disclaimer: The content of this report does not necessarily reflect the views of Defra, nor is Defra liable for the accuracy of the information provided, nor is Defra responsible for any use of the reports content.

3 Table of Contents List of Figures... 4 List of Tables... 5 Executive Summary... 6 Introduction Project Background Aims and Objectives Structure of this report Part 1: Predicting the effect of fishery area closures on long-lived sessile species Introduction Results Part 2: Field surveys of benthic species and assemblages Introduction Methods Data analysis Part 3: Field Surveys of reef associated nekton Introduction Methods Part 4: Scallops Introduction Methods Data analysis Part 5: Socio-economic implications Introduction Methods Main results Enforcement of closure Discussion Part 6: Conclusions and programme for future work Acknowledgements References Appendix... 51

4 List of Figures Figure 2.1 Figure 2.2 Figure 2.3 Figure 2.4 Figure 2.5 Figure 2.6 Figure 2.7 Figure 3.1 Figure 4.1 Figure 4.2 Figure 4.3 Figure 4.4 Figure 4.5 Figure 4.6 Figure 5.1 Figure 5.2 Figure 5.3 Figure 5.4 Location of towed video transects in Lyme Bay Area designations of sites within each treatment (1, 2, 3, or 4) for use in PERMANOVA analyses Location of diver survey sites in Lyme Bay Diver surveying species present in a 0.5 x 0.5 m quadrat in Lyme Bay Mean abundance of Eunicella verrucosa populations in Lyme Bay. Graphs represent abundance in different areas as determined in Figure 2.4. Error bars are Standard Error Mean abundance of Phallusia mammillata populations in Lyme Bay. Graphs represent abundance in different areas as determined in Figure 2.4. Error bars are Standard Error Mean abundance of target species from belt transects for 2008, 2009 and 2010 for sites a) within the open controls, b) new closures and c) closed controls. Error bars are standard deviation Location of sites for baited video sampling Map showing the location of scallop survey sites during the 2010 field season Diagram detailing the survey method for scallop collection (not to scale) Photographs of Pecten maximus showing a) dimensions used for width and height measurements, and b) clear growth rings on a 3 year old specimen Evidence of damage in the growth ring of two Pecten maximus specimens The underside of 2 Pecten maximus shells showing the attachment of a) bryozoans and b) numerous Crepidula fornicata Pecten maximus a) after lower shell has been removed and b) showing where the gonad was cut prior to weighing (dotted line) and the location of the foot Comparisons based on a) wet weight, and b) value of landings one year before and one year after the closure for all species landed by static gear, towed gear, and scallops from vessels that had fished in ICES rectangles 30E6 and 30E7 Value of landings ( ) for fishing vessels that use static gear and those that use towed gear comparing the value of landings when fishing had been conducted inside or outside of the closed area Raw sightings data records from 2005 to 2009 collected by the Devon Sea Fisheries Committee (DSFC). The positions shown are sightings from a patrol boat that were normalised with the patrol boat effort and are presented for a) static and b) towed gear types Proportion of divers who reported changes to diving trips to Lyme Bay in the first and second phase of surveys

5 Figure 5.5 Figure 5.6 Changes in various aspects of dive businesses comparing responses for the first and second surveys Number of trips made by Charter Boat Operators in 2008 and 2009 showing the type of activity hired for Figure 5.7 Location of charter operations in 2008 and 2009 List of Tables Table 2.1 Fieldwork dates for Diver Surveys & Towed Video Table 2.2 Definition of treatments from which survey sites were selected Table 3.1 Fieldwork dates for Baited Underwater Video Table 5.1 Table 5.2 Table 5.3 Table 6.1 Perceived changes in income, total costs, travel time to fishing sites, number of fishing trips made and trip duration for towed and static gear fishermen a) immediately after the closure (towed, n = 15, static, n = 25), and b) one year after the closure (towed, n = 12, static, n = 18) in Lyme Bay Changes in the a) number of vessels and b) number of trips one year before and after the closure for static and towed gear showing the number fishing inside or outside of the closed area Relative importance (%) of the main impacts reported by fish merchants (Respondents include a total of seven key fish merchants from Devon and Dorset) Reporting deadlines for the period

6 Executive Summary Introduction Lyme Bay, located off the south west coast of England is home to some of the UK s most important reef habitat and is considered to be both nationally and internationally important in ecological and conservation terms. It is also an important area for commercial fishing and has a substantial number of recreational users. In July 2008 the UK Government (Defra) acted on guidance from Natural England that advised the closure of a 60 nm 2 area of Lyme Bay to bottom towed fishing gear. This closure took the form of a Statutory Instrument and had the primary aim of allowing the recovery of benthic biodiversity. The reefs have now also been put forward by Natural England as part of the Lyme Bay and Torbay candidate Special Area of Conservation (csac). Following the closure, the Marine Institute, University of Plymouth was awarded the contract for a three year project funded by Defra and Natural England that aims to assess both the ecological and socio-economic implications of the closure. The project partners are the Marine Biological Association of the UK, Plymouth Marine Laboratory Limited, and Marine Bio-images. The project has been designed around eight main objectives: (1) To identify and select a number of representative species within the study area that could signify changes within the ecosystem. Selection of such indicator species should include representatives from the full range of life strategies used by benthic species in the study area (but selection of species should consider their wider application for monitoring of MPAs); (2) To develop a cost-effective sampling design for the monitoring of benthic recovery within the closed area of Lyme Bay; (3) To quantify the recovery of the indicator species within the closure compared to areas which continue to be fished using bottom towed gear; (4) To quantify the effects of the closures on reef-associated nekton, compared to areas which continue to be fished using towed bottom gear; (5) To assess the long-term effects of fishery area closures on long lived and sessile benthic species; (6) To collect and store samples of selected benthic species for future DNA analysis;

7 (7) To quantify and assess any effects on adult scallop populations resulting from the closure; (8) To assess any socio-economic impacts (e.g. diversification, gear changes, changes to areas fished, effort changes) which result from the closure restrictions. This document is the second Annual Report produced by the project team and reports on work completed to date. Some preliminary data analysis is included, but, as all analyses are not yet complete, full results will not be presented until the Final Report which is due at the end of March Part 1: Predicting the effect of fishery area closures on long-lived sessile species It is not possible to assess the long-term effects of fishery area closures in Lyme Bay directly within the time frame of this project because, as they are often slow growing, the recovery time for many long-lived sessile species is substantial. The approach here was to make an informed assessment of the likely outcomes of fishery area closures using the best available knowledge from the scientific and grey literature. Detailed results are presented in the Objective 4 report (October 2010), but the main findings of this work are summarised here. The majority of species investigated were found to be slow growing with prolonged maturation, and over 66 % have no regeneration capacity, meaning that their regeneration is dependent on larval dispersal. Literature searches revealed a lack of published studies that met the search criteria, highlighting the importance of this work in improving the understanding of the effects of fishery area closures on hard substrate, temperate benthic communities, particularly if key aspects of benthic monitoring are continued. Part 2: Field surveys of benthic species and assemblages There is a need to develop cost-effective and innovative ways of monitoring changes in biological assemblages within MPAs due to the current increase in their designation. The ecological survey was designed with this in mind. Fieldwork included towed video surveys of the benthos, and diver surveys for detailed, site specific documentation of change over time within a specific cobble reef habitat. Survey sites were selected to control for habitat and fishing effort variability. To allow changes to be detected as a result of the closure, four treatments were defined: (1) New closure (previously fished, now closed to mobile ground gear) (2) Closed controls (previously unfished under a voluntary agreement, continuing to be unfished)

8 (3) Near open controls (previously fished, continuing to be fished, < 5 km from closure boundary) (4) Far open controls (previously fished, continuing to be fished, > 5 km from closure boundary) Survey sites have now been successfully sampled in 2008, 2009 and 2010 and data sets are now complete. Data analysis includes estimates of abundance data for mobile species and ten large obvious benthic species as well as detailed frame grab analysis for a subset of 30 frames per tow. Frame grab analysis is in progress, and in the same week that this report was due, the extraction of data from the video footage for all three years was completed. Initial investigations have shown changes in abundance of indicator species that are typical of an assemblage of organisms in various stages of recovery. PERMANOVA has revealed significant differences in abundances of some species between areas within and between treatments. Post hoc testing is needed before any conclusions can be drawn, but this investigatory dataset has shown that there is a likely emerging trend for some species towards recovery within the new closure. Initial observations of the diver surveyed belt transects also suggests that there will be differences in species abundance between treatments and years. The need for ongoing monitoring is clear as these emerging trends may be the beginning of a recovery phase, or they may not. We will not know for possibly several more years due to the long-lived nature of the key species, but if there is recovery it is vital to capture this in order to inform other potential closures and provide robust evidence to support their effectiveness. Part 3: Field surveys of reef-associated nekton Static baited underwater video sampling was used to quantify the diversity and structure of nektonic and mobile benthic faunal assemblages. Surveys were successfully repeated in 2010 and data analysis is underway. Analysis will provide an understanding of the differences between nekton and benthic mobile species in terms of species diversity, abundance and assemblage structure between seasons, (spring, March, and summer, July), spatial treatment differences (CC, NC and OC), and temporal treatment differences. Full analysis will be presented in the Final Report. Part 4: Scallops Adult scallop populations were surveyed to assess differences in population structure within and outside the closure. This work was incorporated into the quadrat surveys undertaken by the dive team and therefore survey sites were predetermined. Scallops were collected, and data on their length, width, height, and age recorded. Damage to their shells was also noted. Data analysis is underway and will be

9 reported in the Final Report. Data from the towed video analysis regarding total scallop abundance will also be included. Part 5: Socio-economic implications Socio-economic assessment used questionnaires and interviews to determine the effect of the closure on various stakeholder groups commercial fishermen, sea anglers, dive businesses, divers, charter boat operators, owners of local hotels, and fish merchants. Secondary data in the form of catch data from the Marine Management Organisation (MMO) relating to wet weight and value of landings reported by vessels that have fished within International Council for the Exploration of the Sea (ICES) statistical rectangles 30E6 and 30E7 was also used to study changes in fishing effort following the closure. Data on sightings was also obtained from the Devon Sea Fisheries Committee (DSFC) and the MMO and was used to explore changes in areas fished. Preliminary results indicate that the closed area has imposed a number of costs and benefits on the stakeholders. For fishermen, impacts differ depending on their choice of gear and fishing location. Those who fish within the closure have seen an increase in fishing effort as they are able to increase the number of crab and whelk pots they deploy. However, outside the closure, conflicts have been reported between static and mobile gear fishermen. Despite this, analysis of landings data has indicated that there have been minimal impacts on the average incomes and profits of fishermen and fish merchants. For all other stakeholder groups minimal changes have been reported. However, these impacts are immediate and all stakeholders shared the view that the full impacts of the closure are yet to be realised. Part 6: Conclusions and program for future work To date, this project has identified tentative evidence for the recovery of long lived sessile species within the 60 nm 2 closure in Lyme Bay. Preliminary analyses have revealed a statistically significant effect of treatment for the towed video data, with sites within the new closure significantly more abundant in sessile benthic organisms than those outside that continue to be fished. Furthermore, socio-economic analysis has shown that although there have been some negative effects of the closure on fishermen, overall the impact on stakeholders has been minimal, and landings data has revealed that incomes and profits have not been greatly impacted. However, despite these positive trends, the time period of this project is not adequate to allow the clear, unequivocal recovery of long lived sessile indicator species to be determined. The results we have to date show an emerging trend that may be the beginning of a recovery phase, but continued monitoring is essential to determine whether this is the case; these data would be of national and international importance in terms of assessing the value of MPAs and similar closures.

10 Introduction Project Background Lyme Bay, located off the south west coast of England is home to some of the UK s most important reef habitat and is considered to be both nationally and internationally important in ecological and conservation terms. The bay is an important fishing area for mobile gear such as scallop dredges, and static gear such as crab and lobster pots. It also supports a large number of recreational users, including sea anglers and divers. Since 2001, some areas of the Lyme Bay reefs have been protected through voluntary agreements with local fishermen. The size of these areas was increased in However, following advice given by Natural England, the UK Government (Defra) closed a 60 nm 2 area in July 2008 to bottom towed fishing gear under a Statutory Instrument to provide protection against damage to the seabed. Consequently scallop dredgers and demersal trawlers are no longer permitted to fish within the closed area, but it remains open to fishers using pots and nets, sea anglers, scuba divers, and other recreational users. The bay has also now been put forward as a candidate Special Area of Conservation (csac) by Natural England under the EC Habitats Directive. Aims and Objectives There are a multitude of factors (both ecological and socio-economic) which are affected by this type of fisheries closure. A consortium of scientists, lead by the University of Plymouth Marine Institute, is carrying out a comprehensive study which aims to monitor both the ecological and socio-economic impacts of this closure. With these aims in mind the project has been designed around the following objectives: (1) To identify and select a number of representative species within the study area that could signify changes within the ecosystem. Selection of such indicator species should include representatives from the full range of life strategies used by benthic species in the study area (but selection of species should consider their wider application for monitoring of MPAs); (2) To develop a cost-effective sampling design for the monitoring of benthic recovery within the closed area of Lyme Bay; (3) To quantify the recovery of the indicator species within the closure compared to areas which continue to be fished using bottom towed gear;

11 (4) To quantify the effects of the closures on reef-associated nekton, compared to areas which continue to be fished using towed bottom gear; (5) To assess the long-term effects of fishery area closures on long lived and sessile benthic species; (6) To collect and store samples of selected benthic species for future DNA analysis; (7) To quantify and assess any effects on adult scallop populations resulting from the closure; (8) To assess any socio-economic impacts (e.g. diversification, gear changes, changes to areas fished, effort changes) which result from the closure restrictions. The completed study will aim to provide valuable information on the effectiveness of MPAs at delivering conservation gains, and in determining the kinds of information that is essential to assessing their socio-economic implications. In addition, they can be used to provide further detail on where fisheries management and conservation objectives could be integrated. The project is now in its final year and will be completed in March This report outlines the work completed to date, and provides some preliminary analysis of the data collected. Detailed analyses are currently in progress and this will be presented once all datasets are complete in the final report. Structure of this report This report is presented in several sections. In general, they correspond to the objectives as outlined above; however, in some cases it was more logical and reader-friendly to cover several objectives within a single part. Each part is intended to stand alone, but should be read in the context of this introduction, and in conjunction with the overall conclusions at the end of the report. The timing of this document falls just three months before the completion of the Final Report. To minimise repetition between reports and to focus resources and efforts on completing full analyses on time, final analyses will be presented and conclusions drawn mostly in the Final Report.

12 Part 1: Predicting the effect of fishery area closures on long-lived sessile species 1.1 Introduction It is not possible to assess the long-term effects of fishery area closures in Lyme Bay directly within the time frame of this project because, as they are often slow growing, the recovery time for many long-lived sessile species is substantial. The approach here was to make an informed assessment of the likely outcomes of fishery area closures using the best available knowledge from the scientific and grey literature. This comprised two components: (1) An investigation into the sensitivity and recoverability of the long-lived sessile species recorded in the study area of Lyme Bay using biological traits analysis (2) A review of scientific literature into the long-term effects of fishery area closures on benthic fauna at a national, regional (NE Atlantic) and global scale to put findings into wider context. In addition, this work was supported by predictive species distribution modelling of the pink sea fan, Eunicella verrucosa, to gain a spatial dynamic to the assessment of long term change and inform on priority areas for long-term monitoring. 1.2 Results The results are reported in detail in the Objective 4 report, but in brief, it was found that recoverability traits varied amongst the sessile species. Over a third of the sessile long-lived species in Lyme Bay were classified as fragile according to their life history traits. Many of these (> 66 %) have no regeneration capacity, meaning that their recovery is dependent on larval dispersal. Larval dispersal distance was categorised as short (< 0.1 km), medium (0.1 1 km) and long (> 10 km). Of the species lacking regeneration mechanisms, most could travel moderate to long distances as larvae which could enable recolonisation from outside the Bay. However, for species such as Amphianthus dorhni (sea fan anemone) which can neither regenerate nor travel far as a larvae; recoverability is low. Other traits that were considered in this analysis were growth and age at maturity, since these can determine the speed of recolonisation. Most of the species investigated here were slow growing with prolonged maturation. The analysis of studies reporting recovery in temperate reef communities following protection was constrained by the paucity of suitable studies that fulfilled the search criteria. While there is a body of literature on recovery (or lack of) in tropical reef

13 systems and also a significant amount of information available on the impacts of fisheries activity on benthic communities, there are few cases where the recovery of sessile benthic communities has been documented. Where there are studies that show recovery, it is often reported for mobile rather than sessile species. Findings are highly variable, with dramatic changes in benthic community composition in some areas (e.g. Southern Italy (Guidetti 2007)) but others have remained unchanged (e.g. Lundy, (Hoskin et al,. 2009)). The predictive modelling work on E. verrucosa compared Generalized Linear/Additive Model (GLM/GAM) and Maximum Entrophy (Maxent) results in terms of predictive accuracy and generated predictive maps of E. verrucosa distribution from the different modelling approaches. These were appraised in terms of the ecological insight gained from the modelling exercise and their applicability to future monitoring effort within the Lyme Bay closed area. All three approaches predicted that a large proportion of the closed area is suitable for supporting the pink sea fan. In reality, many of these areas are associated with absence records (false positives). Overall the Maxent model outperformed the other models in all but one of the model performance indicators and on face value one might use this model in preference to the GLM output to support spatial management measures.

14 Part 2: Field surveys of benthic species and assemblages 2.1 Introduction With the current increase in designation of MPAs there is a need to develop costeffective and innovative ways of monitoring changes in the biological assemblages to enable effective management to be implemented. With this in mind, the specific objectives of this monitoring program were: (1) To design and implement a cost-effective and low impact sampling regime to quantify abundance of benthic biota (2) To establish monitoring sites for small and large scale surveys (3) To collect and analyse base-line data as soon as practicable after the implementation of the closure (2008) (4) To repeat the data collection surveys annually for two years (2009 & 2010) The fieldwork aspect has now been completed (Table 2.1), and data analyses are underway. Preliminary results are presented here and full analyses will be presented in the Final Report. Table 2.1: Fieldwork dates for Diver Surveys & Towed Video Date Purpose Status Diver Surveys Completed Towed Video Completed Diver Surveys Completed Towed Video Completed Diver Surveys Completed Towed Video Completed 2.2 Methods Full methods have been reported in the 2009 Annual Report (Attrill et al., 2009), and Sheehan et al. (in revision) and have therefore only been summarized here.

15 Two main methodological elements were selected for the monitoring of change in benthic species abundances and assemblage structure over time. These were designed to provide quantitative, robust information at a range of scales: Annual towed High Definition HD (large scale) video transect sampling to quantify broad-scale changes of benthic assemblages over time. Annual surveys by divers using quadrat and fixed transects (small scale) for detailed and site specific documentation of change over time within a specific cobble reef habitat. Survey locations were selected following consultation with DSFC, the Marine Fisheries Agency (MFA, now MMO) and Devon Wildlife Trust (DWT) to ensure that locations controlled for habitat and fishing effort variability. Target areas were defined (Table 2.2), and from these, sites were determined during the 2008 field season using local knowledge and site investigations by divers. Table 2.2: Definition of treatments from which survey sites were selected Treatment New closure Closed controls Near open controls Far open controls Definition Previously fished, now closed to mobile ground gear Previously un-fished under voluntary agreement, continuing to be un-fished Previously fished, continuing to be fished, < 5km from closure boundary Previously fished, continuing to be fished, > 5km from closure boundary It was predicted that the initial baseline (2008) data would show the closed controls to be different from both open controls and the new closure. Over time, a recovery scenario predicts that species composition in the new closures will move to a state approximating that of the closed controls Towed video Towed video analysis was used to sample abundance of benthic taxa using a low impact, cost-effective methodology. A total of 64 sites were identified, with 16 sites surveyed per treatment (Figure 2.1). The survey has now been successfully completed in the summers of 2008, 2009 and 2010.

16 Figure 2.1: Locations of towed video transects in Lyme Bay Data extraction is comprised of two stages: (1) Quantification of the abundance of ten of the conspicuous indicator species, and all of the mobile benthic species from entire video transects. (2) Detailed frame grab analysis on a subset of 30 frames per transect where all species are identified and abundances recorded In the same week as this report was due, extraction of data from the video footage for all three years was completed. Initial analyses of this dataset are included in this report by means of a preliminary indication of the results to come, which will be presented in the final report. PERMANOVA was undertaken on the relative abundance (per unit area) for each pre-selected indicator species (Jackson et al., 2008) and all of the mobile benthic species observed to test for differences between years (2008, 2009, 2010), area (1, 2, 3 or 4, see Figure 2.2) and treatment, nested in area (CC, NC, NOC, FOC).

17 Figure 2.2: Area designations of sites within each treatment (1, 2, 3, or 4) for use in PERMANOVA analyses Data extraction from the frame-grabs is not yet complete and will be presented in the final report. With the two sets of data complete and a comprehensive dataset compiled of encrusting and sessile species from the frame grabs and the more conspicuous, less abundant and/or mobile species identified from the video, it will be possible to appropriately assess with confidence the effect of the SI on the species associated with the seabed in Lyme Bay, in the two years that it has been in place Random Quadrat and Fixed Transect Diver Survey To provide more detailed, site-specific data complementing the large scale towed video camera survey, a smaller scale diver survey was conducted, primarily through the use of quadrats, focussing on the mixed sediment (referred to as cobble reef ) habitat. Detailed surveys of change in species assemblage over time were carried out by SCUBA divers. During July 2010, Marine bio-images survey divers successfully relocated and resurveyed all ten fixed monitoring stations (Figure 2.3). As in previous years the diving

18 survey work was conducted from the 10 m, Lyme Regis based workboat Miss Patty, with skipper John Walker. The dive survey team (Colin Munro, Lin Baldock, Sean Lindsley-Leake and Katharina Brown) remained the same, ensuring maximum continuity in species identification. Figure 2.3: Location of diver survey sites in Lyme Bay All stations lay between 20 and 22 m chart datum in areas of level seabed with similar exposure to tidal streams and wave action. Their location was selected from areas of cobble reef to ensure habitat homogeneity. As in previous years, at each station, eight 0.5 x 0.5 m quadrats were dropped at random locations around the station markers, surveyed and photographed (Figure 2.4). Species from a predetermined list were recorded quantitatively, and a total species list was produced from four quadrats.

19 Figure 2.4: Diver surveying species present in a 0.5 x 0.5 m quadrat in Lyme Bay Each quadrat was photographed using a 10 megapixel DSLR and wide-angle lens (approximately 100 degree angle of acceptance allowing a camera-to-subject distance of about 0.4 m) to ensure image clarity. Images were collected as RAW files and have been given limited processing to improve contrast and resolution prior to being archived on CD as high quality JPEG files. An 8 x 2 m belt transect fixed between two markers at each station was also surveyed. This focussed on larger, more widely distributed species that are less likely to fall, or be accurately recorded within quadrats. The target species for which counts were performed were Eunicella verrucosa, Alcyconium digitatum, Pentapora foliacea, Cliona celata (raphus form only), Phallusia mamillata and all erect branching axinellid sponges over 3 cm in height (grouped as a single category). 2.3 Data analysis Data collection is now complete (Table 2.1) and analysis underway. Data presented here are preliminary, and full analysis will be included in the Final Report.

20 2.3.1 Towed video analysis Initial investigations into the changes in abundance of indicator species are giving results typical of an assemblage of organisms exhibiting various stages of recovery. This would be expected based on the fact that these species were selected to represent a range of life histories, tolerances to disturbance and abilities to recover from disturbance (Jackson et al., 2008). There also appear to be geographical differences between area (Figure 2.2), which will be formalized once post-hoc tests have been carried out. For example, E. verrucosa populations were significantly different between areas within and between treatments (PERMANOVA P < 0.05, see Appendix A). Figure 2.5: Mean abundance (number of individuals) of Eunicella verrucosa populations in Lyme Bay. Graphs represent abundance in different areas as determined in Figure 2.4. Error bars are Standard Error

21 Post hoc tests are required to formally explain results; however, it appears that there are geographical differences between the west and east of the bay within the New Closure (Figure 2.5, see Appendix). The abundance of pink sea fan appears to be increasing in sites on the eastern side, but not on the west (Figures 2.2 & 2.5, see Appendix). In areas which continue to be fished, pink sea fans continue to be mostly absent. Similarly, populations of the sea squirt Phallusia mammilata had significantly different abundances between treatment and area (P < 0.05 PERMANOVA, Appendix A) and showed no apparent change in fished areas, nor within tows to the far western area of the New Closure (Figures 2.2 & 2.6, Appendix A). Increases in abundance of this species however, appear to be occurring further east in the bay within the New Closure (Figures 2.2 & 2.6, see Appendix). Figure 2.6: Mean abundance (number of individuals) of Phallusia mammillata populations in Lyme Bay. Graphs represent abundance in different areas as determined in Figure 2.4. Error bars are Standard Error

22 Without appropriate post hoc tests, it is too early to draw any conclusions, but, on the basis of this investigatory dataset, there is likely to be an emerging trend for some species towards recovery. Although this is not statistically demonstrated here, there may also be a geographic effect, in that some species are showing apparent recovery in the east, but not in the west. The need for ongoing monitoring is clear, these emerging trends may be the beginning of a recovery phase, or they may not. We will not know for possibly several more years, so the opportunity exists for further benthic monitoring to provide the first robust data on recovery of such temperature reefs that will be vital to inform future closures Random quadrat and fixed transect diver survey Preliminary analysis has been completed and initial results are presented below. Statistical analysis has not yet been conducted due to time constraints and therefore only basic observations can be presented at this stage. Figure 2.7 shows mean abundance and standard deviation for the six target species recorded by belt transects at sites within Open Controls, New Closures and Closed Controls in 2008, 2009 and a) Open controls

23 b) New closure c) Closed controls Figure 2.7: Mean abundance of target species from belt transects for 2008, 2009 and 2010 for sites a) within the open controls, b) new closure and c) closed controls. Error bars are standard deviation

24 These initial observations reveal that in the open controls, species abundance is low. P. foliacea is the most abundant species, and with the exception of A. digitatum which has a very low abundance for all three years, no other species is present consistently across sampling seasons. However, with the exception of C. celata in 2008 in the new closure, all six target species are present for all years in the new closure and closed controls. Repeated measures ANOVA will be used to look at the statistical significance of the data and allow trends to be examined, and full results and analyses will be presented in the final report.

25 Part 3: Field Surveys of reef associated nekton 3.1 Introduction In this study, we used the well established methods of static baited video sampling (e.g. Stobart et al. 2007) to quantify the diversity and structure of nektonic and mobile benthic faunal assemblages. The specific objectives were: (1) To establish baited video sampling stations for time-series monitoring of changes in species abundance and assemblage structure over time (2) To quantify differences between nektonic and mobile benthic species and assemblages between different treatment types, as defined in Part 3. (3) To quantify seasonal differences between nektonic and mobile benthic species and assemblages, in the context of different treatments (Attrill et al., 2009). 3.2 Methods The 2010 sampling followed the methods detailed in Attrill et al. (2009). Figure 3.1: Location of sites for baited video sampling

26 Six sites were surveyed per treatment (CC, NC & NOC) giving a total of eighteen, and each site consisted of 3 replicates (Figure 3.1). Data collection is now completed for this work (Table 3.1) and analysis is underway. Full methods and analysis for 2009 are presented in the 2009 Annual Report (Attrill et al, 2009). Findings confirmed that the baited video method is capable of detecting changes between treatments, and analysis of the species and higher taxonomic group levels showed that there are distinct suites of species characteristic of impacted or un-impacted sites (Attrill et al., 2009). Table 3.1: Fieldwork dates for Baited Underwater Video Date Purpose Status Baited Underwater Video Completed Baited Underwater Video Completed Baited Underwater Video Completed Baited Underwater Video Completed Analysis of the 2010 data will allow these trends to be further examined, and will provide an understanding of differences between nekton and benthic mobile species in terms of species diversity, abundance and assemblage structure between seasons, (spring, March, and summer, July), spatial treatment differences (CC, NC and OC), and temporal treatment differences which will show how the response variables have changed between 2009 and 2010 within treatments. If positive temporal differences are detected in the NC and CC, but not the OC, then we will be able to draw positive conclusions regarding the success of the SI for the recovery of mobile species associated with the sea bed in Lyme Bay.

27 Part 4: Scallops 4.1 Introduction At the start of this project it was asked that we undertake a scallop spat study to understand whether the SI will affect king scallop Pecten maximus populations over time. The study was commissioned too late in the year to set up scallop spat collectors and after some consideration it was also thought that the amount of effort necessary to detect this change far exceeded this project. Additionally, genetic analysis, to determine different scallop populations and to quantify where spat were coming from and going to, and scallop collection up and down the coast from Lyme Bay would need to be undertaken. As a compromise it was agreed that instead we would refocus the objective to concentrate on the adult populations and begin to look for differences in scallops inside and outside of the box using divers to collect them. The health of scallop populations could then be assessed and any changes over time detected. To make this economically feasible (as it was not part of the original study plan), dives which were necessary to collect scallops were incorporated into the quadrat work undertaken by Colin Munro during the first week of August 2009 (Attrill et al., 2009). Here we present the scallop collection methods to quantify changes in scallop populations as a result of the cessation of scallop dredging in the Lyme Bay SI. The analyses and results will be presented in the Final Report. 4.2 Methods Surveys to compare scallop populations were conducted over two consecutive summers (2009 and 2010). Scallop populations were measured in three of the four treatment areas, at sites as determined by the diver surveys (Figure 4.1). (1) New closure (previously fished, now closed to mobile ground gear) (2) Closed controls (previously unfished under a voluntary agreement, continuing to be unfished) (3) Near open controls (previously fished, continuing to be fished, < 5km from closure boundary)

28 Figure 4.1: Map showing the location of scallop survey sites during the 2010 field season Sampling was undertaken by the dive team using SCUBA (nitrox), alongside the divers survey work from the vessel Miss Pattie. A shot line was deployed within a 200 m radius of the permanent markers at each station to ensure that scallop work and diver survey work remained separate. Two divers then deployed a 10 m transect north from the shot (replicate 1) with 1 diver length between the shot and the start of the transect to ensure independence of the replicates. A 2 m pole was held perpendicular to the transect line between the divers to standardise the area from where the scallops were collected (Figure 4.2). Every P. maximus found in the 2 m x 10 m transect was collected. This was then repeated east, south and west of the shot, with the scallops from each transect collected in different bags, giving a total of 4 replicates per site (Figure 4.2).

29 Figure 4.2: Diagram detailing the survey method for scallop collection (not to scale) The scallops collected were measured at the surface for width, length (Figure 4.3a) and height (highest point on upper shell to lowest point on lower shell). They were then aged by counting their growth rings, and damage to their shells was recorded (present/absent). a) b) Figure 4.3: Photographs of P. maximus showing a) dimensions used for width and height measurements, and b) clear growth rings on a 3 year old specimen The age of P. maximus is determined by counting rings that are laid down annually (Allison et al., 1994). A thumb placed at the hinge end of the shell represents one

30 year s growth, and from there the growth rings can be counted starting from year 2 (Figure 4.3b). By inspecting these growth rings it is also possible to determine if the scallop shell has been damaged. A uniform set of growth rings curving across the shell indicates no damage, whereas an uneven ring with obvious abnormalities is likely to have been damaged (Figure 4.4). Figure 4.4: Evidence of damage in the growth ring of two P. Maximus specimens Damage to the growing edge of the upper shell was ignored as this may have occurred during collection. Conspicuous epibionts, with the exception of algae, attached to the scallop shells were also identified to Class level and recorded (Figure 4.5a & b). Figure 4.5: The underside of 2 P. maximus shells showing the attachment of a) bryozoans and b) numerous Crepidula fornicata

31 A subsample of 4 individuals from each transect was sacrificed so that total body mass and gonad weight could be measured. All other scallops were returned at sea. Prior to weighing the whole scallop any large aggregations of Crepidula fornicata were removed, but all other epibionts were left on the shell. Each scallop was opened by cutting the adductor muscle from the lower shell, the internal organs were removed and the gonad was cut anterior to the foot and subsequently weighed (Figure 4.6a & b). Figure 4.6: P. maximus a) after lower shell has been removed and b) showing where the gonad was cut prior to weighing (dotted line) and the location of the foot. 4.3 Data analysis Data collection is now complete and analysis is underway. This will be reported in full in the Final Report in March 2011 and will include the scallop abundance data derived from the towed video footage.

32 Part 5: Socio-economic implications 5.1 Introduction As conservation theory and practice moves away from excluding resource users and towards creating partnerships with them, it is becoming increasingly clear that conservation of marine ecosystems is as much about understanding people as it is about understanding ecological processes. Social and economic factors can influence whether and how individuals and communities exploit resources or cooperate to conserve them. Integrating high quality social science at conservation sites can help to adapt and refine management strategies to reflect the needs and desires of the stakeholders. It also enables the selection of strategies that are appropriate for local conditions, and ensures that scarce resources are used more wisely by targeting specific strategies at the segments of the population where they are most needed. Objective 7 therefore focuses on the socio-economic implications of the 60 nm 2 closure in Lyme Bay to scallop dredging and bottom trawling. The specific objectives of this socio-economic assessment were to: (1) Quantify the socio-economic changes resulting from the closure for: a. Fishermen, such as diversification and gear changes, changes in areas fished, landings and fishing effort; b. Tourism and recreational activities; c. Supporting industries e.g. fish merchants and processors; and d. Enforcement agencies (2) Examine the perceptions, and changes in attitudes to the closed area amongst local and wider communities 5.2 Methods The socio-economic impacts of the closure on the various stakeholder groups have been assessed using a combination of primary and secondary data Primary data Primary data collection has mainly employed surveys. Seven questionnaires have been developed and used to obtain socio-economic details of the main user groups of Lyme Bay including commercial fishermen, sea anglers, dive businesses, divers,

33 charter boat operators, owners of local hotels and fish merchants. A combination of interview methods has been used to collect data on costs, income and perceptions of the various stakeholders, including online surveys, face-to-face, postal and telephone interviews. A full explanation of the methods used to survey each stakeholder category and the selection of respondents is presented in our earlier report (Mangi et al., 2009). During the second phase of the survey which was completed in April this year (2010), we invited the same people to participate as in the first survey i.e. 157 commercial fishermen, 10 dive businesses, 57 charter operators, 62 UK angling clubs, 180 dive clubs, 68 local hotels and 7 fish processors. Data analyses have focused on comparing results of the first survey which was conducted immediately after the closure was implemented, and the second survey that was conducted one year later. Given that only demersal mobile gear is restricted in the closed area, analyses have been completed with data pooled into either towed or static gear types. Data on the perceptions of fishermen towards changes in income, costs, travel time to fishing sites, and fishing duration are reported based on the proportion of fishermen who participated in the survey. We have also completed interviews with various stakeholder groups (including static and towed gear fishermen, sea anglers, charter boat operators, dive businesses and divers) aimed at assessing the social impacts of the closure. The focus of these has been changes in stakeholder behaviours and conflicts that could be attributed to the closure Secondary data Data on the volume of species landed by different gear types have been obtained from the MMO for each vessel that has fished in ICES statistical rectangles 30E6 and 30E7 from 2005 to 2009 (for a map on the ICES rectangles and position of closure please see our earlier report Mangi et al 2009). The catch data includes the wet weight and value of landings reported by fishermen and fish merchants to the MMO at various ports around the South West of England. We understand that these data could be underestimating the actual landings and fishing effort since a high proportion of inshore fishing activities do not report their catches. We have, however, used these data sets as they present the official landings and fishing effort. Based on information from enforcement agencies and data on sightings collected by the DSFC using their patrol boat, daily catches for each vessel were matched to the corresponding location of the vessel on the date when fishing was done. Officers of the DSFC patrol the waters around the coast of Devon to monitor byelaws and in the process record positions of fishing vessels within the 6 mile limit. The assumption was that the catch of each vessel came from the location at which the vessel had been sighted. This is not true for all vessels especially the big ones and therefore

34 was only applied to vessels that were sighted and those that the DSFC officers were sure that they would only fish in certain areas e.g. because they were less than 10m and would therefore only fish up to the 2 mile limit. This underestimates the value of catches coming from the various areas but because we could not get disaggregated data using a combination of expert judgements (officers from SFCs), the sightings data (air, navy patrol and SFCs patrol boat) together with the landings data has allowed us to make such comparisons. This is however a first step in this analysis and will be improved as more information becomes available. The fishing locations were categorised as either inside or outside the closed area and the value of landings from each were then plotted and compared based on the gear types used. To study changes in fishing effort following the closure, the number of vessels and number of trips made per month was used. To explore changes in areas fished, data on sightings of fishing vessels have been obtained from the DSFC and the MMO. These data are based on sightings made via surveillance aircraft and patrol boats. Air and sea surveillance for the closed area follows an enforcement procedure which confirms the exact position of the vessel and its observed activity to a level of evidence that is sufficient for prosecution if appropriate. The sightings data set includes the position of the vessel (latitude and longitude), the activity (fishing or steaming) and the ICES rectangle used for all vessels (both under and over 15 m). Sightings data from 2005 to 2009 were imported into ArcGIS and overlaid on a base map of the Lyme Bay area. Only vessels sighted fishing were mapped according to the fishing gear used whilst vessels sighted steaming were removed from the analysis. Annual comparisons from (using a July to June year) were made based on grouped sightings data to reflect annual variation before and after the closure. Data on the costs of enforcing the closure restrictions have been obtained from the MMO and DSFC. Enforcement costs were gathered from the deployment of surveillance aircraft and Royal Navy fisheries protection vessels by the MMO, and a patrol vessel by DSFC. At the time of reporting, no infringements of the Lyme Bay closed area have been detected by the enforcing authorities. 5.3 Main results Impacts on commercial fishermen a) Diversification and gear changes Four fishermen indicated that they have changed gear as a result of the closure. The majority are still using their preferred gear type while two fishermen have changed

35 gear type, but not as a consequence of the closure. For example, one sold his fishing vessel because of restrictions to catch quotas. During the social interviews however, some fishermen suggested that the number that have changed gear may possibly be as high as nine or ten. We are currently investigating this issue further. b) Perceived changes to costs and incomes The majority of fishermen (73 %) who use towed gear claim that their income has decreased (Table 5.1). This is a view shared by 40 % of static gear fishermen, while 52 % of claim that fishing incomes have remained at similar levels to before the closure (Table 5.1). Between 68 and 83 % of all fishermen in both surveys claimed that total costs have increased (Table 5.1). The reasons provided for this increase include a reduction in scalloping, an increase in fuel costs, and increased duration of fishing. Static gear fishermen also claim that the fall in income is due to the displacement of towed gear fishermen into fishing grounds traditionally used by static gear fishermen. Another reason given was that the quality of scallops harvested from outside the closed area is lower and hence they fetch lower prices. Over 75% of towed gear fishermen have seen increases in the time taken to travel to fishing sites, while most of the static gear fishermen have seen no change as their fishing grounds have remained the same (Table 5.1). Table 5.1: Perceived percentage change in income, total costs, travel time to fishing sites, number of fishing trips made and trip duration for towed and static gear fishermen a) immediately after the closure (towed, n = 15, static, n = 25), and b) one year after closure (towed, n = 12, static, n = 18) in Lyme Bay a) Immediately after closure Perceived changes to: Income Total costs Travel time to fishing sites Number of trips per month Fishing duration Gear Increased (%) Decreased (%) Same (%) No response (%) Towed Static Towed Static Towed Static Towed Static Towed Static

36 b) One year after closure Perceived changes to: Income Total costs Travel time to fishing sites Number of trips per month Fishing duration Gear Increased (%) Decreased (%) Same (%) No response (%) Towed Static Towed Static Towed Static Towed Static Towed Static Both towed and static gear fishermen still make the same number of fishing trips per month, but fishing duration has increased for most towed gear fishermen due to the need to access more distant fishing sites (Table 5.1). Fishermen were asked if they had any other sources of income in order to determine their level of dependence on fishing, in particular fishing in Lyme Bay. Most of them claimed that they had no other income and attributed 98 to 100 % of their monthly income to fishing in Lyme Bay. c) Changes in wet weight and value of landings The value of landings for static gear fishermen from July 2007 to June 2008 (one year before the closure) was very similar to the value of landings from July 2008 to July 2009 (one year after the closure) at around 2.2 million (Figure 5.1b). Similarly, the total value landed by mobile gear including scallop dredging one year before the closure was very similar to the value of landings one year after the closure at 1.1 million.

37 Figure 5.1: Comparisons based on a) wet weight, and b) value of landings one year before and one year after the closure for all species landed by static gear (pots, nets), towed gear (scallop dredgers and demersal trawlers), and scallops from vessels that had fished in ICES rectangles 30E6 and 30E7 Landings for scallops indicate a 26.7 % increase from 560,610 the year before closure to 710,844 afterwards (Figure 5.1b). These landings data reveal that the majority of the catches for both static and towed gear fishermen have been coming from outside the closed area (Figure 5.2).

38 Figure 5.2: Value of landings ( ) for fishing vessels that use static gear and those that use towed gear comparing the value of landings when fishing had been conducted inside or outside of the closed area. Fishing effort data show that the number of vessels fishing inside the closed area using static gear has remained between 28 and 31 vessels per month one year before and after the closure (Table 5.2). The number of vessels using static gear fishing outside the closure remained the same one year before and after the closure. Similar results are evident for fishing vessels using towed gear. The number of trips

39 however rose for both those fishing inside and outside of the closed area from 246 to 281 (Table 5.2). Table 5.2: Changes in number of vessels and number of trips one year before and after the closure for static and towed gear showing the number fishing inside or outside the closed area based on sightings data. Towed gear is not allowed inside the closure hence the blanks. Static inside Static outside Towed inside Towed outside Mean SD Mean SD Mean SD Mean SD Number of vessels One year before closure One year after closure Number of trips One year before closure One year after closure d) Changes in areas fished and distribution of fishing effort Analyses of vessel density on the sightings data from 2005 to 2009 showed that fishing intensity in the ICES rectangles 30E6 and 30E7 fluctuated widely prior to the closure (Figure 5.3). The number of fishing vessels using static gear in the now closed area remained fairly similar from 2005 to 2008 but went up after the closure was introduced. These activities have spread to new areas inside the closure as most fishermen are deploying more pots. According to the DSFC the number of pots deployed per fisherman has doubled inside the closure (B. Lawrence, Pers. Comm.). Between 2005 and 2008, fishing vessels using towed gear dominated the area which is now closed, but vessel numbers fluctuated throughout the year. Spatial distribution of fishing effort by towed gear fishermen indicates that the most intensively dredged areas after the introduction of the closure are now the inshore waters around Exmouth (Figure 5.3).

40 a) Static gear b) Towed gear Figure 5.3: Raw sightings data records from collected by DSFC for a) static, & b) towed. Positions are patrol boat sightings normalised with patrol boat effort. Dates clockwise from top left: Jan 05 June 06, July 07 June 08, July 06 June 07 & July 08 Dec 09