Mapping Fishing Effort through AIS Data

Several research initiatives have been undertaken to map fishing effort at high spatial resolution using the Vessel Monitoring System (VMS). An alternative to the VMS is represented by the Automatic Identification System (AIS), which in the EU became compulsory in May 2014 for all fishing vessels of length above 15 meters. The aim of this paper is to assess the uptake of the AIS in the EU fishing fleet and the feasibility of producing a map of fishing effort with high spatial and temporal resolution at European scale. After analysing a large AIS dataset for the period January-August 2014 and covering most of the EU waters, we show that AIS was adopted by around 75% of EU fishing vessels above 15 meters of length. Using the Swedish fleet as a case study, we developed a method to identify fishing activity based on the analysis of individual vessels’ speed profiles and produce a high resolution map of fishing effort based on AIS data. The method was validated using detailed logbook data and proved to be sufficiently accurate and computationally efficient to identify fishing grounds and effort in the case of trawlers, which represent the largest portion of the EU fishing fleet above 15 meters of length. Issues still to be addressed before extending the exercise to the entire EU fleet are the assessment of coverage levels of the AIS data for all EU waters and the identification of fishing activity in the case of vessels other than trawlers.JRC.G.3-Maritime affair

Sustainability now or later? Estimating the benefits of pathways to maximum sustainable yield for EU Northeast Atlantic fisheries

8 pages, 3 figures, 3 tables, supporting information http://dx.doi.org/10.1016/j.marpol.2016.06.015Most countries have the goal to manage their fisheries to achieve a combination of biological, economic, social, and political objectives [1] and [2]. This is also the case for the EU's Common Fisheries Policy (CFP). According to Article 2 of the CFP [3]: “The CFP shall ensure that fishing and aquaculture activities are environmentally sustainable in the long-term and are managed in a way that is consistent with the objectives of achieving economic, social and employment benefits, and of contributing to the availability of food supplies”. [...]Peer Reviewe

Mass flow and variability in screw feeding of biomass powders – relations to particle and bulk properties

Biomass powders are often cohesive, have low bulk density and poor material flow characteristics which causes interruptions and variations in feeding systems. In this study, a range of biomasses - commercial charcoal, torrefied Norway spruce stem wood, non-treated Norway spruce stem wood, and reed canary grass - was milled (screen size: 1 mm) using two different milling methods; cutting mill and hammer mill, to form eight types of biomass powders. Powders were analyzed for loose density, Hausner ratio, compression ratio, angle of repose and for size and shape distributions. Size and shape were determined by mechanical sieving and optical particle size and shape analysis. Additionally, yield loci and wall yield loci were determined through standard bulk solids testing methods. Screw feeding properties of the eight biomass powders were determined by feeding the materials in a twin screw feeder - at constant rpm and at a constant feeding rate of 1 kg/h. Correlation analysis and principal component loadings were used to describe relations between material properties and feeding characteristics. When materials were fed at a constant rpm, feeding variability was closely correlated to the powders’ angle of repose (long time step) and Hausner and compression ratio (short time step)

The mouthpiece chamber vacuum pattern indicates the cessation of milk flow and suits as an indicator to reduce teat end vacuum at a quarter level.

We investigated the suitability of the quarter mouthpiece chamber vacuum (MPCV) as an indicator for cessation of quarter milk flow to potentially adjust the teat end vacuum at a quarter level. We tested the hypothesis that a MPCV increase is a clear indicator of quarter milk flow cessation. In addition, we tested if a quarter individual vacuum reduction at MPCV increase reduces the mechanical impact on the teat. Ten dairy cows were milked twice daily with a quarter specific vacuum supply with continuously high (51 kPa; TRT51) or low vacuum setting (41 kPa; TRT41), or high vacuum setting combined with a quarter specific vacuum reduction by 10 kPa immediately after the quarter specific MPCV increase (TRT51/41). Whole udder milk flow was continuously recorded. Each treatment was repeated at 4 subsequent milkings. The high vacuum settings (TRT51; TRT51/41) reached higher values in peak flow rate and average milk flow and consequently shorter machine-on time. The time from start of milking until the steep increase of the MPCV was shorter in front than rear quarters, and hence the time from start of MPCV increase until end of milking was longer in front than rear teats. Teat condition of the right front teats was measured for teat wall diameter by ultrasound and teat tissue thickness by cutimeter at 5 and 20 min after each experimental milking. The teat measurements were taken at the teat tip (distal barrel) and 2 cm above the teat tip (proximal barrel). The proximal teat wall diameter tended to be higher in TRT51 than in TRT41, both 5 and 20 min after milking. The distal teat wall diameter at 5 min was greater in TRT51 than in TRT41. In TRT51/41 the teat wall diameter at both locations was intermediate, not significantly different from either TRT51 or TRT41. The distal teat tissue thickness was greater in TRT51 than in TRT41, and tended to be greater in TRT51/41 than in TRT41 at 5 min (P = 0.08). The proximal teat tissue thickness at 5 min was higher in TRT51 and TRT51/41 than in TRT41. The teat tissue thickness decreased from 5 to 20 min only in the proximal barrel. The quarter individual MPCV increase appears to be a suitable indicator of the cessation of milk flow. The lack of a significant reduction of mechanical impact on the teat by a reduced vacuum of 41 kPa indicates that the vacuum level chosen may be still too high under conditions of a separate vacuum supply for each quarter which prevents a vacuum drop caused by the whole udder milk flow

Infrared Thermography and Ultrasonography to Indirectly Monitor the Influence of Liner Type and Overmilking on Teat Tissue Recovery

Eight Danish Holstein cows were milked with a 1-mm thick specially designed soft liner on their right rear teat and a standard liner mounted under extra high tension on their left rear teat. Four of the animals were overmilked for 5 min. Rear teats were subjected to ultrasound examination on the first day and to infrared thermography on the second day. Teats were submersed in ethanol 20 min post-milking on the second day. Ultrasonography measurements showed that teat canal length increased by 30–41% during milking. Twenty minutes after milking, teats milked with modified standard liners still had elongated teat canals while teats milked with the soft liner were normalized. Overmilking tended to increase teat wall thickness. Approximately 80% of variability in teat canal length, from before teat preparation to after milking, could be explained by changes during teat preparation. Thermography indicated a general drop in teat temperature during teat preparation. Teat temperature increased during milking and continued to increase until the ethanol challenge induced a significant drop. Temperatures approached pre-challenge rather than pre-milking temperatures within 10 minutes after challenge. Teat temperatures were dependent on type of liner. Mid-teat temperatures post-challenge relative to pre-teat preparation were dependent on overmilking. Thermography and ultrasound were considered useful methods to indirectly and non invasively evaluate teat tissue integrity

The Resource Rent in Sweden's Fishery

The report is an analysis of the resource rent in the Swedish fishery, produced as a contribution to the new strategic plan for the Swedish fishery in the years 2007-2013 according to the draft EU regulation for the EFF (European Fishery Fund). A model has been produced based on linear programming. The study originates from the situation in 2004 and with this basis different scenarios are calculated for the coming years. Special emphasis has been put on the optimal resource rent and the maximum number of employed persons within the sector. The actual current situation points to great deficits, and also to a fishery overcapacity. This is due to too many vessels sharing a resource too small. The fixed costs of the overdimensioned fishing fleet turn potential profits into great losses. The effects of restructuring the fishing fleet could be large. An optimal economic scenario suggests that more that 50% of the fleet should be restructured, and that more than 40% of these should even be scrapped, i.e. removed from the fleet altogether. The optimal scenario further suggests that only one-fifth of the total quotas should be landed; catching the remaining four-fifths is not profitable. The goal of utilizing the fish resource is not only to maximize profits, but also for example to spread the use regionally or to maximize employment. The resource rent is expected to be zero at a maximized level of employment. The results show that a restructuring can increase employment as well, even with half of the current utilization of the resource, i.e. with half of the current total catch. The net- and hook segment and the small pelagic vessels are winners from an employment perspective. This is not only due to low incomes per fisherman (which is absolutely not true for the small pelagic vessels), but also to that the profits in these segments can be used to increase total capacity, i.e. the number of vessels. The future is uncertain. Technological development and increasing prices and costs are some of the potential changes that can be expected to take place, but the calibers of these changes are unpredictable. The Baltic Sea seal population is another threat worth considering. A likely future scenario does nevertheless look bright from an economic perspective. The results indicate that restructuring can make the fishing fleet generate a relatively large profit without overexploiting the resource

Report on the Workshop on Transversal Variables. (Linking economic and biological effort data (call) design). 19th -23rd January 2015

The Workshop on the Transversal Variables took place in Zagreb from the 19th to 23rd of January, 2015 mainly to tackle the issues related to the increasing need of having fisheries fleet economic data and fisheries biologic data on a level of disaggregation that would allow a proper interoperability between datasets to underpin bioeconomic modelling. For that, several analyses were carried out and conclusions taken. These analyses were : 1. comparison of economic and biological effort data calls both with respect to their level of resolution and the landings and effort values obtained from equivalent aggregations was performed. This was compared to what would be needed in order to undertake bioeconomic modelling for a chosen management plan. 2. The description of how MS are calculating effort variables and a proposal on the way forward to harmonize approaches, 3. Conclusions on how to harmonize levels of resolution, the variable definitions and the codification in use amongst data calls, in order to make them comparable and based on coherent standard codifications.JRC.G.3-Maritime affair