378 research outputs found
The importance of rebuilding trust in fisheries governance in post-Brexit England
No full textThe sustainable management of common pool resources, like fisheries, relies heavily on trust and reciprocity between managers and stakeholders (fishers). The UK Fisheries Act of 2020 and the Joint Fisheries Statement of 2022 seek to reinvent post-Brexit fisheries governance and the economic and environmental sustainability of the sector. Management of the fisheries sector through Fisheries Management Plans (FMPs) is still under development but changes in governance arrangements are likely to significantly impact fishers’ livelihoods. This highlights a need for improved collaboration between fishers and the governing institutions. Using a novel survey design, representatives of the English fisheries sector were surveyed to capture their level of different forms of trust (rational, affinitive, system-based) towards national and regional governing institutions. Overall, low levels of trust were found, although regional institutions (i.e., Inshore Fisheries and Conservation Authorities) were more trusted than national institutions (i.e., Department for Environment Food and Rural Affairs and Marine Management Organisation). Exploring different forms of trust revealed nuance between the institutions and distinctive regional differences. To build on this, interviews were conducted revealing feelings of apathy and conflict towards the governing institutions rather than inclination towards collaborating. Trust has a role in fostering more resilient fisheries management and fishers discussed the need for sustained institutional efforts to rebuild trust post-Brexit through greater transparency, face-to-face interaction, and meaningful consultation. Our research also reveals that FMPs will need to factor in geographical differences and that current institutions will need to work more collaboratively in order to foster local adaptive management
The future of marine fisheries management and conservation in the United Kingdom: lessons learnt from over 100 years of biased policy
No full textMarine wild-capture fisheries depend on the capacity of the ocean to provide a flow of harvestable resources to sustain the industry. Paradoxically, conventional fishing often undermines these resources by degrading the environment and overexploiting fish stocks. Many UK fisheries have declined for over a century due to a biased focus on their social-economic value and lack of recognition that they are social-ecological systems and need to be managed as such. With the UK’s recent transition to an independent coastal state, the Fisheries Act (2020) and associated Joint Fisheries Statement provide an opportunity to correct this. Focusing on the ecological foundations, a more sustainable future for UK fisheries may be achieved by: (1) implementing a conservative quota setting system based on Maximum Sustainable Yield (MSY), defined as that which would occur when the biomass of a population of the target species is at 50% of that estimated at carrying capacity, to set catch limits rather than targets. The biomass of fish stocks should be allowed to regenerate to a minimum of 120% of that which will achieve MSY to provide a buffer against the uncertainty in ecological response to climate change. (2) Fishing capacity should be reduced while redistributing a greater share of the quota to sectors of the fleet that are demonstrably more sustainable; recognising that short term compensation may be required by some to mitigate the impacts of displaced activity until the benefits of stock recovery are realised. (3) Greater restrictions should be applied to ensure the most damaging fishing techniques (e.g. bottom trawling and dredging) are prohibited as appropriate in the network of marine protected areas. Protection should be enforced to promote the regeneration of degraded habitats and restoration of fish populations to help achieve the objectives as set out in the Act
Future advances in UK marine fisheries policy: Integrated nexus management, technological advance, and shifting public opinion
No full textHaving left the European Union, the UK Fisheries Act (hereafter referred to as the Act) provides a framework that may advance sustainable marine resource management. This requires the bias towards social-economic concerns to be recognised, and greater emphasis to be placed on securing the natural capital to support fisheries. A Joint Fisheries Statement (JFS) to be published in 2022 by the UK’s devolved fisheries authorities will set out how the objectives of the Act will be achieved. While recognising the value of principles of the Act, this article challenges the current management framework in light of the wider challenges in fisheries practice. It argues for more emphasis on ecological and fisheries regeneration, and maximising societal benefits rather than yields. Three recommendations are provided: (1) an integrated and more holistic Fisheries-Energy-Environment Nexus resource management approach would better utilise systems thinking to optimise trade-offs and synergies between competing domains to achieve fisheries, conservation and other environmental goals (e.g. delivering the national net zero strategy); (2) the use of best available technologies as is reasonably practicable to monitor compliance and facilitate enforcement should be a regulatory requirement under the JFS; (3) the fisheries and marine conservation science community should work with other stakeholders to change the media narrative, public opinion, and political direction away from a “business-as-usual” model that risks long-term degradation of the marine fisheries resource
Evaluation of Brazilian woods as an alternative to oak for cachaca aging in cask - their antioxidant ability:chapter 25
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A 3-D data smoothing algorithm
No full textThe algorithm presented in this report is designed for use in smoothing 3-D data at NUWES. It uses fourth-order sequential differences to screen the data for outliers and then a special form of least-squares smoothing is performed to select an appropriate low-order polynomial and fit it to seven-pont data segments. (Author)N0025381WR70012NAResearch and Engineering Department, Naval Undersea Warfare Engineering Station, Keyport, Washingtonhttp://archive.org/details/3ddatasmoothinga00tys
Graduate School of Architecture, Class of 1999
No full textFront row (left to right): Tania A. Tully, Cherise J. Bell, Natalie Pugh Stewart, Pop Aaron Chayovan, Jim Agutter, Tak-On Sze, Ashley G. Lemon, Kuo-Ching Liao, Eric Browning, Matthew Thomas. Middle row (left to right): Carmen Aroztegui, Mary E. Willis, Daniel Clavin, Erik Tuomy, Beatrice Lufkin, Robert Anthony Fabri, Hans Cerny, Ed Merrill, E. Benjamin Rogers, Bryce Allison, J. Jason Foster, Hans Hoffman. Back row (left to right): Eric Petersen, Matthew B. Anderson, Benjamin Allred, Stefan Richter, Robert Fornataro, Brian David Parker, Terance B. White, David D. Cox.Portraits -- Group portraits; Photographs -- Positives -- Photographic print
Interactions between piscivorous coral reef fish and their prey
No full textPredation appears to play an important role in the regulation of populations and communities of coral reef fish. Interactions between piscivorous coral reef fish and their prey have rarely been studied, however. The aim of this thesis was to examine how piscivorous coral reef fish respond to fluctuations in the abundance of their prey and to use this information to predict their impact on prey populations. In the first part of this thesis a broad suite of piscivorous species at Lizard Island on the Great Barrier Reef were studied, while in the second part I concentrated on the influence of prey abundance on the ecology of two common piscivores, the rock-cods, Cephalopholis cyanostigma and C. boenak (Serranidae).
The distribution, abundance and community structure of piscivorous fish at Lizard Island was examined initially. Central to this was the trial of a new baited census technique used to bring cryptic species into view. Traditional census methods (strip transects) were found to underestimate the abundance of cryptic piscivores by approximately 50%. In contrast, the baited technique accounted for approximately 90% of cryptic fish. Strip transects were found to be more appropriate for conspicuous, mobile species, however, as the baited method attracted mobile fish from an unknown area. By combining the baited method for cryptic species with the transect method for mobile species a relatively accurate picture of the piscivorous fish community at Lizard Island was obtained. Abundance of piscivores varied at both a large scale (between different zones of exposure kilometres apart) and a local scale (between sites hundreds of metres apart). This variation may have implications for the impact of piscivores on prey.
The abundance of piscivores and their prey was then monitored over an 18 month period in two different habitats, patch and contiguous reef. This allowed two hypotheses to be examined: (1) that piscivores would aggregate in areas of high prey abundance and (2) this aggregation would cause density-dependent mortality of prey. The abundance of both piscivores and prey was consistently higher on patch reefs than on contiguous reef. There were also strong positive relationships between prey and piscivore abundance within sites throughout the study. Mortality of prey was density-dependent over the 6 month period it was monitored. Mortality of prey was positively related to piscivore abundance but was also positively related to the ratio of prey to piscivores. This suggested piscivore abundance only partly explained patterns of prey mortality. Recruitment patterns did not explain the relationship between prey and piscivore abundance, suggesting post-settlement processes were responsible. Tagging of Cephalopholis cyanostigma and C. boenak was used to examine the contribution of movement. Movement between sites or habitats was rare for both species, however, suggesting it did not explain large-scale patterns of abundance. In contrast, at a local scale territory size was inversely proportional to prey density and a change in current direction caused a corresponding small-scale movement of both piscivores and prey. Hence, although the mechanisms could not be fully determined, the abundance of piscivores and their prey appeared to be strongly linked.
At the same sites and times as above the influence of prey abundance on the dietary composition, prey selection and feeding rates of Cephalopholis cyanostigma and C. boenak was examined. Gut contents were collected mainly from regurgitated samples, to allow the same populations to be monitored over time. Both species were found to be over 90% piscivorous with prey fish of the families Apogonidae, Pomacentridae and Clupeidae dominating the diet. The interacting effect of fluctuations in prey abundance and patterns of prey selection caused diet to vary both temporally and spatially. Mid-water schooling prey belonging to the family Clupeidae were selected for over other families. In the absence of these prey apogonids were selected for over more reef-associated pomacentrids. Feeding rates of both rock-cods were much higher in summer than winter and in summer they concentrated on small, recruit sized fish. There was little variation in feeding rates between patch and contiguous reef, however, despite apparent differences in prey abundance. The combination of high densities, high feeding rates and selection for certain sizes and types of prey suggested the two rock-cod species were having a considerable impact on populations and communities of their prey.
The life history characteristics and population structure of Cephalopholis cyanostigma and C. boenak on patch and contiguous reef were also examined over a 2 year period. Knowledge of these patterns can provide indirect evidence of different processes limiting populations and the mechanisms that determine these effects. Tetracycline injection of tagged fish allowed for validation of annual increments in the otoliths of both species. Estimates of growth rate could therefore be obtained from both size-at-age data and recaptured tagged fish. Both species were relatively long-lived (32 years for C. cyanostigma and 16 years for C. boenak) and slow growing. Size-at-age curves of both species were almost identical on the two reef types, although growth of tagged C. boenak was slightly higher on patch reefs. Growth of tagged C. cyanostigma was significantly higher in summer than spring but this may have been due to either water temperature or prey abundance. Age and size-at-maturity also showed no difference between patch and contiguous reef. Age and size structures were similar on the two reef types for C. cyanostigma but there were more small / young C. boenak on patch reefs. C. boenak may undergo an ontogenetic shift from patch to contiguous reef. Based on longevity, mortality of both species was also similar on the two reef types. Sex ratios of C. boenak indicated they were monogamous on patch reefs but polygamous on contiguous reef. This may have been due to increased predation pressure on patch reefs. Overall, despite apparent differences in prey abundance there were few differences in the life history and population structure of the rock-cods on patch and contiguous reef. Differences in prey abundance appeared to be compensated for by territory size and the abundance of competitors and predators of the rock-cods themselves.
The behavioural and developmental responses of Cephalopholis boenak to variation in prey abundance were further examined in a field experiment. Two hypotheses were tested: (1) that C. boenak would move from areas of low to high prey density and (2) that feeding and growth rates of C. boenak would be higher in areas of high prey density. Small patch reefs, which were equivalent in terms of habitat type, isolation and competitor and predator density, were used in the experiment. Over the 6 months of the experiment 31% of tagged C. boenak moved between patch reefs, all from reefs of low to high prey density. Feeding rates were also higher on patch reefs of higher prey to piscivore ratio. Due to few recaptures of tagged fish on reefs of low prey density, growth rates could not be compared within the experiment. Both feeding and growth rates on the experimental reefs, however, were much higher than on natural patch reefs over the same period. These patterns corresponded with much higher prey densities on experimental reefs. Hence these results suggest that growth of C. boenak was food-limited on natural patch reefs studied and that C. boenak responds both behaviourally and developmentally to variation in prey abundance.
In summary, this study provided considerable evidence that piscivorous coral reef fish are limited by the availability of prey and are therefore likely to be in competition for this resource. This food-limitation appeared to cause numerical, behavioural and developmental responses of piscivores to variation in prey abundance. These responses may also have a stabilising effect on prey populations and communities. Predation by piscivorous fish is therefore likely to have been at least partly responsible for recent observations of density-dependent mortality of coral reef fish. This study has therefore supplied further support for the regulatory role of predation in coral reef fish communities
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