Résultats de la recherche

1. Comparison of two methods to assess fish losses due to depredation by killer whales and sperm whales on demersal longlines

   to 2013), accounting for spatial variations of depredation levels. In the first method, fishing data ... second method used the differences in the proportion of grenadiers (Macrourus spp.) between non ... conservation issues. However, estimating the amount of resource depredated can be especially challenging when ... depredation occurs on fish in the marine environment. This is the case for killer whales (Orcinus orca) and ... standard errors of the mean loss of CPUE in the presence of odontocetes were multiplied by the total ... 679 ± 74 tonnes were depredated. The second method used the differences in the proportion of ... consider- ably harder to estimate in the marine environment where the initial state of the depredated ... (Ramos- Cartelle and Mejuto, 2008). In the context of declining world fisheries (Pauly et al., 2005 ...

   Science Journal Paper : CCAMLR Science, Volume 22 (CCAMLR Science, Volume 22) : 1–14 : Auteur(s): Gasco, N., P. Tixier, G. Duhamel and C. Guinet

2. Investigations of required sampling regimes for environmental parameters

   / Description:  The sensitivity of different sampling regimes in identifying inter-annual changes in ... monthly mean temperature over two years with a significance α of 0.05 and a power P of 0.8. Sampling wind ... monthly mean log-transformed wind speed α of 0.05 and P of 0.9. File:  35-Agnew.pdf ... Paper Title:  Investigations of required sampling regimes for environmental parameters Abstract ... errors are especially important in studies affecting conservation issues, where the penalty of not ... day) would be sufficient to identify changes of 10% in log mean wind speed. The analysis above does ... necessary to distinguish between changes in the monitored system induced by harvesting of particular ... in particular the presence of cyclic phenomena. Subsequently, sensitivity analyses were performed on ...

   Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/7 (Selected Scientific Papers, SC-CAMLR-SSP/7) : 561–573 : Auteur(s): Agnew, D.J.

3. Line weights of constant mass (and sink rates) for Spanish system Patagonian toothfish longline vessels

   with seabirds. The weights typically used are collections of rocks enclosed in netting bags. During ... the option of substituting steel weights for rock weights while remaining in compliance with the sink ... rates associated with the line-weighting provisions of Conservation Measure 25-02. Both the Spanish ... relationship between the sink rates of longlines equipped with bags of rocks (4, 6 and 8 kg) and those with ... . Significant conservation benefits obtained from the use of a new fishing gear in the Chilean Patagonian ... collections of rocks enclosed in netting bags. During fishing operations the netting bags abrade on the ... modified version of the former method to avoid fish loss by toothed whales) were tested in the experiment ... exceeded those of the Spanish system, ranging from 0.68 m s–1 (4 kg rocks) to 1.31 m s–1 (8 kg steel) in ...

   Science Journal Paper : CCAMLR Science, Volume 15 (CCAMLR Science, Volume 15) : 93–106 : Auteur(s): Robertson, G., C.A. Moreno, E. Gutiérrez, S.G. Candy, E.F. Melvin and J.P. Seco Pon

4. Selectivity of standard Polish commercial trawl codends on Antarctic fishing grounds

   Abstract / Description:  Selectivity studies were carried out for two types of steelon codends used in ... of 4.2 mm. The studies covered 6 major fish species. It appears from the study that Antarctic icefish ... and bumphead notothenia are subject to selection during trawling, although the effectiveness of this ... process- especially in the latter case- is not satisfactory. Scotia Sea icefish, Chaenodraco wilsoni, and ... mean length "Iw" of fish inside the codend in percent; the value of this index gives some idea as to ... in the cover "mo" to mean weight of fish inside the codend "mw" expressed in percent; the value of ... this index illustrates the weight of fish escaping from the codend in comparison with the mean weight ... mesh size in the cod ends tested Parameter Nominal No. of mesh sizes codend Mean mesh size (mm) 80 ...

   Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/5 – Part II (Selected Scientific Papers, SC-CAMLR-SSP/5 – Part II) : 107-142 : Auteur(s): Zaucha, J.

5. A risk-management framework for avoiding significant adverse impacts of bottom fishing gear on Vulnerable Marine Ecosystems

   . Temporal scales must be matched to the recovery scale of VMEs, which are probably in the order of many ... measure in 2007 to ensure that significant adverse impacts of bottom fishing gear on Vulnerable Marine ... Ecosystems (VMEs) are avoided. Due to the high levels of uncertainty surrounding both the evidence of VME ... presence and the consequences of interaction with different types of gear, a risk-management framework is ... must be matched to the recovery scale of VMEs, which are probably in the order of many decades or even ... activities in marine areas beyond national jurisdic- tion has grown considerably over the course of the 21st ... would thus be viewed as VMEs in the context of their particular disturbance regimes. In 2005, UNGA ... progress with a view to further recommendations (UNGA, 2005). In response, a report on the impacts of ...

   Science Journal Paper : CCAMLR Science, Volume 16 (CCAMLR Science, Volume 16) : 177–193 : Auteur(s): Martin-Smith, K

6. Acoustic data analysis and models of krill spatial distribution

   / Description:  Acoustic data obtained on 4-5 January 1987 aboard the R/V Professor Siedlecki were used in three ... descriptors of krill spatial aggregation: power spectra for krill biomass fluctuations in space, semivariogram ... (spatial autocorrelation of krill biomass) and the frequency distribution of krill biomass estimate. The ... wavenumber spectrum resembles a white noise at scales of 2-20 km, although at scales smaller than 1 km the ... obtained on 4-5 January 1987 aboard the RN ProfesSor Siedlecki were used in three descriptors of krill ... the techniques of spectral analysis to examine the spatial scale dependence of variability in ... temperature, phytoplankton (chlorophyll-a) and krill biomass in the Antarctic Ocean south of Africa. They ... of krill biomass. In other words, the spectra of temperature and chlorophyll appeared very similar ...

   Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/5 – Part I (Selected Scientific Papers, SC-CAMLR-SSP/5 – Part I) : 311–329 : Auteur(s): Morin, A., A. Okubo and K. Kawasaki

7. Sensitivity analysis for parameters of predatory species CCAMLR Ecosystem Monitoring Program

   such a treatment of data obtained at the Magnetic Island Adélie penguin colony in Prydz Bay in the 1987 ... Program Abstract / Description:  Following the request of the Scientific Committee of CCAMLR to conduct ... Paper Title:  Sensitivity analysis for parameters of predatory species CCAMLR Ecosystem Monitoring ... /88 and 1988/89 breeding seasons. The data on the following parameters were analyzed: adult weight on ... with normality (K-S; p > 0.235 in all cases)(Figures 4a to 4d) and the mean fledging weights of the ... decide what sample size would be necessary if we wished to detect a true fluctuation in the mean of any ... detecting differing degrees of change in the mean, at different levels of statistical significance and ... should reflect the importance of each five-day period in calculation of the annual mean. In this report ...

   Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/6 (Selected Scientific Papers, SC-CAMLR-SSP/6) : 411–432 : Auteur(s): Whitehead, M.D.

8. Fishing for toothfish using pots: results of trials undertaken around South Georgia, March–May 2000

   commercial viability of this fishing method for toothfish fisheries in the CCAMLR Convention Area. While the ... toothfish was notably lower than that achieved in the longline fishery. Importantly, the use of pots ... , March–May 2000 Abstract / Description:  During the period March to May 2000, the UK undertook trials of ... method successfully caught D. eleginoides, there was a large by-catch of crab species. The catch rate of ... achieved in the longline fishery. Importantly, the use of pots eliminated bird by- catch. To capitalise on ... with other areas in the Convention Area, still catches significant numbers of seabirds. Calculations ... incidental mortality of seabirds should be reduced as much as in toothfish fisheries in the Convention Area ... commercial toothfish pot fishing around South Georgia, the UK proposed to perform trials of this method in ...

   Science Journal Paper : CCAMLR Science, Volume 8 (CCAMLR Science, Volume 8) : 93–105 : Auteur(s): Agnew, D.J., T.M. Daw, G.M. Pilling and M.G. Purves

9. Spawning locations of mackerel icefish at South Georgia

   . There are also indications of a possible second spawning season in January, although the evidence is ... :  Historical information on the distribution of spawning and larval mackerel icefish (Champsocephalus gunnari ... inshore spawning at South Georgia during April within and close to the bays on the north side of the ... island. Some spawning almost certainly occurs over much of the island shelf, although is this appears to ... in Figure 1. The mean number of C. ~ I I I Z I I ~ Y ~ per net was very low during February and ... Rocks. There are also indications of a possible second spawning season in January, although the ... ) reported a catch of 4 000 C, giinnari in a single haul. With the exception of eight small specimens (67 ... spawning stock migrates into the fjords in March. In a study of several species on the South Georgia ...

   Science Journal Paper : CCAMLR Science, Volume 8 (CCAMLR Science, Volume 8) : 107–118 : Auteur(s): Everson, I., A.W. North, A. Paul, R. Cooper, N.C. McWilliam and K.-H. Kock

10. Length-based assessments revisited – why stock status and fishing mortality of long-lived species such as toothfish cannot be inferred from length-frequency data alone

    development. The failure of the tag-recapture program to provide robust assessments in many areas and doubts ... / Description:  In many of CCAMLR’s new and exploratory fisheries, stock assessment techniques are still in ... and fishing mortality from length-frequency data alone. In this paper, a number of length-based stock ... Paper Title:  Length-based assessments revisited – why stock status and fishing mortality of long ... : mean mean c L LZ K L L ¥ -= - (2) where only the mean length Lmean in a sample of fish above ... assessment techniques are still in development. The failure of the tag-recapture program to provide robust ... required for a standardisa- tion of catch rates and estimation of relative abun- dance. In addition, the ... effects of spatial variability in stock distribution and the non-random behaviour of fishing vessels are ...

    Science Journal Paper : CCAMLR Science, Volume 18 (CCAMLR Science, Volume 18) : 57–73 : Auteur(s): Ziegler, P.E., D.C. Welsford and A.J. Constable

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