Risks to North Sea Fish Stocks and Wildlife if Post-Brexit Fishery Negotiations Fail to Reach Agreement on Quotas and Access to UK Waters : Summary Report

"Taking back control of fisheries" became one of the totemic issues uniting supporters of the campaign to leave the EU. Having left, the issue is again high on the agenda in the 'future relationship' negotiations. The UK Government has indicated that getting a better deal for UK fishermen is a "red line" in the negotiations. This includes increases in quota for UK vessels, and restrictions on access to UK waters by foreign vessels. However, the EU has linked access to UK waters and maintenance of quotas enshrined in the Common Fisheries Policy (CFP) with securing tariff-free trade in fish and other products. This report focuses on the North Sea and provides an assessment of the risks to stock and ecosystem conservation associated with the post-Brexit fisheries negotiations. The report first sets out the history behind the allocation of quota shares (Relative Stability) and compares the UK shares with those under proposed alternative rules based on the distribution of fish ("zonal attachment"). Unless a negotiated agreement can be reached to resolve these different views on quota allocation there is a risk that unilateral actions will result in the combined catches by all states exceeding the levels required for long-term maximum sustainable yields. The report sets out a narrative for the impact of such unilateralism on harvesting rates, and then presents results from models which show the risks that these would pose for key fish stocks and wildlife

Risks to North Sea Fish Stocks and Wildlife if Post-Brexit Fishery Negotiations Fail to Reach Agreement on Quotas and Access to UK Waters : Extended Technical Report

"Taking back control of fisheries" became one of the totemic issues uniting supporters of the campaign to leave the EU. Having left, the issue is again high on the agenda in the 'future relationship' negotiations. The UK Government has indicated that getting a better deal for UK fishermen is a "red line" in the negotiations. This includes increases in quota for UK vessels, and restrictions on access to UK waters by foreign vessels. However, the EU has linked access to UK waters and maintenance of quotas enshrined in the Common Fisheries Policy (CFP) with securing tariff-free trade in fish and other products. This extended technical report focuses on the North Sea and provides an assessment of the risks to stock and ecosystem conservation associated with the post-Brexit fisheries negotiations. The report first sets out the history behind the allocation of quota shares (Relative Stability) and compares the UK shares with those under proposed alternative rules based on the distribution of fish ("zonal attachment"). Unless a negotiated agreement can be reached to resolve these different views on quota allocation there is a risk that unilateral actions will result in the combined catches by all states exceeding the levels required for long-term maximum sustainable yields. The report sets out a narrative for the impact of such unilateralism on harvesting rates, and then presents results from models which show the risks that these would pose for key fish stocks and wildlife

Comment on "Fisheries Management"

The recent article by O’Leary et al. (2011) raises an important question about the relationship between science and those who manage fisheries. They contend that fishery managers do not give due cognisance to scientific advice and consistently set Total Allowable Catches (TACs) above values advised by scientists (which they define as ‘‘political adjustment’’). The authors claim that the consequence of this is that there is a high probability of stock collapse in the next 40 years. They use a simulation model to argue that this probability may exceed 80% at the mean level of political adjustment adopted by managers, depending on the degree of environmental variability and life history strategy of the fish

Grey seal predation mortality on three depleted stocks in the West of Scotland : what are the implications for stock assessments?

The decrease in groundfish stocks in the North Atlantic since the mid-1900s coupled with increases in grey seal populations is responsible for an enduring controversy between fishers and conservationists regarding the role seals have played in stock declines. We used a Bayesian state-space model to investigate stock trends in the presence of grey seals and associated MSY reference points in the West of Scotland. This study provides new estimates of seal predation mortality on haddock and whiting and updates the estimates for cod, which together form the traditional main components of the mixed demersal fishery in this area. Grey seal predation mortality is greatest on cod resulting in estimates of total natural mortality higher than those used in the current ICES assessments. Seal predation mortality is low for haddock and whiting. Considering seal predation in stock assessments changes the scale of biomass and fishing mortality estimates for the three stocks. The estimates of F0.1 and FMSY are sensitive to seal predation for cod and whiting but not for haddock. In all cases MSY decreases with increased seal predation

Grey seal predation impairs recovery of an over-exploited fish stock

Grey seal predation has been blamed by fishers for the decline of Atlantic cod stocks and has led to calls for seal culls. In the West of Scotland, estimates of cod consumption by seals have exceeded reported catches and spawning biomass, focussing attention on the interaction between fishers and seals. Bayesian models making different assumptions about seal predation were used to estimate the size of the West of Scotland cod stock between 1985 and 2005 and the mortalities due to fishing and seal foraging. A simple population model was used to identify the likely direction of cod population change at recent mortality rates. All model configurations suggest that the total mortality of cod has remained fairly stable and high for many years regardless of the assumptions on seal predation. The high mortality explains the long-term decline of the stock. The best-fitting model suggests that mortality due to fishing reduced substantially in the decade up to 2005, but has been replaced by increased seal predation mortality on a smaller cod stock. Given total mortality estimates, the stock is unlikely to recover even at present reduced levels of fishing. Synthesis and applications. Our model offers a method of estimating seal predation mortality as part of routine stock assessments that inform fishery management. The analysis shows that predation by seals can be an important component of the total stock mortality. It also shows that assuming invariant natural mortality, as adopted in many standard fish stock assessments, may lead to incorrect perceptions of fishing mortality, over-estimating the benefits of reducing fishing mortality when there is density-dependent predation. It is essential to consider predation by top predators when formulating appropriate advice for managing the fishery

Trematoda (Platyhelminthes) of the Gulf of Mexico

First paragraph: The platyhelminth class Trematoda, consisting of the subclasses Aspidogastrea and Digenea, contains individuals referred to as digeneans, trematodes, or flukes. Aspidogastreans, not digeneans in the strict sense2 number about 80 species in total (Rohde 2005), but adults in the Gulf of Mexico of 4 species have been reported from teleost and chondrichthyan fishes (Hendrix and Overstreet I 977) and one from a turtle (Wharton 1939). Consequently, this chapter deals with trematodes rather than just digeneans, even though all the records but the 5 refer to digeneans. Trematoda is the largest group of platyhelminths, and trematode adults, other than exceptional cases in both Aspidogastrea and Digenea, occur in vertebrates. Rather than being totally restricted to a lumen like members of its sister group Eucestoda (tapeworms), trematode species occur in a variety of sites, exhibiting rather restricted site specificity for each species or higher group. The intriguing situation about trematodes is that they have a molluscan first intermediate host. The larval stage of the aspidogastreans (cotylocidium) does not undergo asexual replication in the mollusk like it does for the digenean counterparts. Digeneans have a series of asexual stages reproducing large numbers of individuals originating as the larva (miracidium) from a single egg that assure transmission and dispersal to a series of one to 3 different, necessary intermediate hosts. With the exception of a few aporocotylids (fish blood flukes) that have larvae developing in polychaetes and maturing in fish, all species in the approximately 17 S families n:quire the molluscan first intermediate host. Of the approximately 18,000 nominal Trematoda. After Overstreet 1973. trematode species worldwide, including well over 5,000 of those from fishes alone (Cribb 2005b), perhaps the largest group of internal metazoan parasites (Cribb et al. 2001), almost all are highly specific for at least the first, second, or final host. On the other hand, at one or more of those 3 stages many digenean species infect several different species of hosts. The number of named or accepted species is low, primarily because of the lack of attention paid to this difficult group of mostly tiny soft-bodied worms. This chapter provides an initial attempt to document records. We do not agree with all, are sure several have been unintentionally omitted, and are sure the lists present a woefully incomplete record because of a paucity of collections and the fact that we have many new records that are not included for lack of time at present

Population trends of bycatch species reflect improving status of target species

Synthesis studies of fish stocks worldwide suggest improving status of mainly target species that are fully assessed. Other analyses, primarily based on catch data alone, but which include a wider range of species as well as bycatch, present a different view. Catch only analyses could be more robust if fishery independent data were used and discards accounted for. We develop a model that uses only survey biomass at length and landings data to estimate fishing mortality, spawning stock biomass (SSB) and discards. An analysis of species from the North Sea shows the model results compare well with most fully assessed stocks. When applied to bycatch species with limited data, trends in fishing mortality and SSB typically reflect those of the target species. In the last decade mean fishing mortality rates have tended to decline while mean spawning stock biomass (SSB) has increased. Despite increasing SSB, recent mean recruitment appears to have been lower than previously which may limit future biomass recovery. Species usually associated with more northerly distributions appear to show the greatest effect of weaker recruitment which may be linked to climate. Estimated discards have tended to decline in magnitude as a result of reduced fishing mortality and associated lower total catches. The model offers a simple way to use both landings and survey data to obtain more detailed population trends for data limited species

Discovery of Five New R Coronae Borealis Stars in the MACHO Galactic Bulge Database

We have identified five new R Coronae Borealis (RCB) stars in the Galactic bulge using the MACHO Project photometry database, raising the total number of known Galactic RCB stars to about 40. We have obtained spectra to confirm the identifications. The fact that four out of the five newly identified RCB stars are ``cool'' (T(eff) 6000 K) suggests that the preponderance of warm RCB stars among the existing sample is a selection bias. These cool RCB stars are redder and fainter than their warm counterparts and may have been missed in surveys done with blue plates. Based on the number of new RCB stars discovered in the MACHO bulge fields, there may be ~250 RCB stars in the reddened "exclusion" zone toward the bulge.Comment: 16 pages, 5 figures, AJ in press High resolution versions of Figures 1 and 2 can be downloaded from http://morpheus.phys.lsu.edu/~gclayton/figs.pdf (more typos corrected

Rate-limiting transport of positively charged arginine residues through the Sec-machinery is integral to the mechanism of protein secretion

Transport of proteins across and into membranes is a fundamental biological process with the vast majority being conducted by the ubiquitous Sec machinery. In bacteria, this is usually achieved when the SecY-complex engages the cytosolic ATPase SecA (secretion) or translating ribosomes (insertion). Great strides have been made towards understanding the mechanism of protein translocation. Yet, important questions remain – notably, the nature of the individual steps that constitute transport, and how the proton-motive force (PMF) across the plasma membrane contributes. Here, we apply a recently developed high-resolution protein transport assay to explore these questions. We find that pre-protein transport is limited primarily by the diffusion of arginine residues across the membrane, particularly in the context of bulky hydrophobic sequences. This specific effect of arginine, caused by its positive charge, is mitigated for lysine which can be deprotonated and transported across the membrane in its neutral form. These observations have interesting implications for the mechanism of protein secretion, suggesting a simple mechanism through which the PMF can aid transport by enabling a 'proton ratchet', wherein re-protonation of exiting lysine residues prevents channel re-entry, biasing transport in the outward direction

Bioeconomic modelling of grey seal predation impacts on the West of Scotland demersal fisheries

The role grey seals have played in the performance of fisheries is controversial and a cause of much debate between fishers and conservationists. Most studies focus on the effects of seal damage to gears or fish and on prey population abundance but little attention is given to the consequences of the latter for the fisheries. We develop a model that quantifies the economic impact of grey seal predation on the West of Scotland demersal fisheries that traditionally targeted cod, haddock and whiting. Three contrasting fishing strategy scenarios are examined to assess impacts on equilibrium fleet revenues under different levels of seal predation. These include status quo fishing mortality (SQF, steady state with constant fishing mortality), open access fishing (bioeconomic equilibrium, BE) and the maximum economic yield (MEY). In all scenarios, cod emerges as the key stock. Large whitefish trawlers are most sensitive to seal predation due to their higher cod revenues but seal impacts are minor at the aggregate fishery level. Scenarios that consider dynamic fleet behaviour also show the greatest effects of seal predation. Results are sensitive to the choice of seal foraging model where a type II functional response increases sensitivity to seal predation. The cost to the fishery for each seal is estimated