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1. Status of krill target strength

   on aggregations of live euphausiids and should not be affected by a frequent cause of bias in single-animal ... there is an empirical basis. The theoretical estimates show a non-monotonic dependence of target strength on both animal ... size and transmit frequency, notwithstanding admitted shortcomings. Some recent single-animal ... of bias in single-animal measurements, namely thresholding. Theoretical estimates for the target strength ... at 30 and 20 kHz. Measurements at 30 kHz were performed near Bouvet Island in December 1979 on krill ... of this ! 108 article, a reasonable fixed value of radius of curvature for the animals is used. In order ... of target strength in the article involve aggregations of animals, it is useful to compare the results ... to thresholding effects discussed earlier in this article and differences in animal type), the structure ...

   Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/9 (Selected Scientific Papers, SC-CAMLR-SSP/9) : 101–126 : Author(s): Foote, K.G., D. Chu and T.K. Stanton

2. Target strengths of Antarctic krill (Euphausia superba)

   kHz TS (dB} at 120 kHz Event Mean no. - no. 1 7 1 9 20 26 28 30 36 37 43 47 50 52 54 ... SC-CAMLR-VII/BG/30 TARGET STRENGTHS OF ANTARCTIC KRILL ... all measurements on the animal of interest, E. superba. The work of K0geler et al. (1987) was noted ... of the object animal by laboratory measurements of density and longitudinal sound speed, among others, 266 ... and 120 kHz in a sheltered bay at South Georgia. The results indicate that the Target Strength values ...

   Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/5 – Part I (Selected Scientific Papers, SC-CAMLR-SSP/5 – Part I) : 265–279 : Author(s): Everson, I., D.G. Bone, J.L. Watkins and K.G. Foote

3. Surveys of breeding penguins and other seabirds in the South Shetland Islands, Antarctica, January-February 1987*

   to have been about 40% overall increase in the chinstrap population in the last 20-30 years, about three ... in the chinstrap population in the last 20-30 years, about three-fourths of the difference between our counts ... Memorandum NMFS Antarctic Marine Living Resources Program (AMLR)) File:  20-Shuford-and-Spear.pdf ... -30 years, about three-fourths of the difference between our counts and previous ones is due to more ... a jugula ire ait augmente globalement d'a peu pres 40% au cours des dernieres 20-30 annees, environ les ... 20-30 anos, aproximadamente tres cuartas partes de la diferencia entre nuestros recuentos y los ... rro rrpeAblAYlI\l1M OlleHKaM. XOTH, KaK Ka)KeTCH, 3a rrOCJIeAHl1e 20-30 JIeT o611\ee KOJII1QeCTBO ...

   Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/4 (Selected Scientific Papers, SC-CAMLR-SSP/4) : 449-451 : Author(s): Shuford, W.D. and L.B. Spear

4. Factors to consider in developing management measures for krill

   from year to year. The various techniques used to estimate the abundance of animal populations also ... OTKPbITbIX-3aKpbITbIX paHoHoB H ce30HOB. IIpe~RaraIOTc~ HeKOTopbIe MepbI no ynpaBReHHIO, KOTopbIe Mor RH ... in the past, and this raises the need for new approaches to fishery conservation. In any case, the problems ... and investment required to ensure that the conservation objectives of the Convention are being met ... Paper Title:  Factors to consider in developing management measures for krill Abstract ...

   Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/7 (Selected Scientific Papers, SC-CAMLR-SSP/7) : 175–187 : Author(s): de la Mare, W.K.

5. 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

   . 0 10 20 30 40 50 0. 0 0. 2 0. 4 0. 6 0. 8 1. 0 Immature selectivity Age (y) Se le ct iv ity ... 0 10 20 30 40 50 0. 0 0. 2 0. 4 0. 6 0. 8 1. 0 Truncated mature selectivity Age (y) 0 10 20 30 ... 2060 0. 0 0. 2 0. 4 0. 6 0. 8 1. 0 Year St oc k st at us 2000 2010 2020 2030 2040 2050 2060 ... 0. 0 0. 2 0. 4 0. 6 0. 8 1. 0 Year 2000 2010 2020 2030 2040 2050 2060 0. 0 0. 2 0. 4 0. 6 0. 8 1. 0 Year Immature ... / Description:  In many of CCAMLR’s new and exploratory fisheries, stock assessment techniques are still in ... development. The failure of the tag-recapture program to provide robust assessments in many areas and doubts ... and fishing mortality from length-frequency data alone. In this paper, a number of length-based stock ... assessment methods are revisited and some limitations in their ability to draw robust inferences about stock ...

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

6. Seabird interactions with longlining operations for Dissostichus eleginoides at the South Sandwich Islands and South Georgia

   . Pieces of the squid Illex argentinus were used for bait, with roughly 20-30 g/hook. Although expensive ... setting, hook vulnerability, CCAMLR INTRODUCTION In recent years, decreases in populations of several ... ). There is increasing evidence tha t these decl ines a re re la ted to inc identa l mortality associated ... % - representing a saving of $A4.9 million and 30 300 albatrosses annually. The Japanese tuna fishery ... mortality was seen and only one bird was caught on a hook; nevertheless many species in these aggregations ... of birds are clearly potentially vulnerable to setting operations in daylight hours. Several species ... grey-headed albatrosses, whose populations are in serious decline at South Georgia, were rare; their ... vulnerability to longlining operations in the South Sandwich Islands may, therefore, be low. Quantitative data ...

   Science Journal Paper : CCAMLR Science, Volume 1 (CCAMLR Science, Volume 1) : 143–153 : Author(s): Ashford, J.R., J.P. Croxall, P.S. Rubilar and C.A. Moreno

7. Estimating optimal observer coverage in the Antarctic krill fishery

   on board for about 30% of that season. They have achieved a rate of krill sampling equivalent to 18 ... , 20% of total season hauls sampled for krill and an equivalent or higher sampling proportion ... suggest that such strategies should be pursued for at least four years before the Scientific Committee ... on board for about 30% of that season. They have achieved a rate of krill sampling equivalent to 18 ... in the Antarctic krill fishery • a target coverage rate of >50% of vessels each year; • a target of >20 ... in g (% ) A ca m ar 20 02 30 7 A cr ux 20 02 35 4 C hi yo ... 46 3 22 4 13 7 61 56 30 41 12 Fe ol en t 20 05 43 1 43 6 32 6 75 ... 78 76 24 18 A tl an ti c N av ig at or 20 05 30 3 54 40 74 29 ...

   Science Journal Paper : CCAMLR Science, Volume 17 (CCAMLR Science, Volume 17) : 139–154 : Author(s): Agnew, D.J., P. Grove, T. Peatman, R. Burn and C.T.T. Edwards

8. An index of per capita recruitment

   recruitment (PCR) is proposed such that where R 1 is the proportion of age-l animals sampled in year ... that: (i) post-recruit mortality does not vary over age or between years; (ii) 100% of age-l animals spawn; (iii ... to recruits per spawner when mortality is constant over all ages and years, and when all age-l animals spawn ... -l animals sampled in year y and M is the post-recruit mortality rate. The intent of the index ... in this time series, first appearing as a large mode at 20 to 30 mm length and in subsequent years ... is the proportion of age-l animals sampled in year y and M is the post-recruit mortality rate. The intent ... or between years; (ii) 100% of age-l animals spawn; (iii) a representative sample of the population ... is constant over all ages and years, and when all age-l animals spawn. These conclusions are insensitive ...

   Science Journal Paper : CCAMLR Science, Volume 7 (CCAMLR Science, Volume 7) : 179–196 : Author(s): Hewitt, R

9. Interactions of Patagonian toothfish fisheries with killer and sperm whales in the Crozet Islands Exclusive Economic Zone: an assessment of depredation levels and insights on possible mitigation strategies

   on D. eleginoides fisheries at the Crozet Islands 0 10 20 30 40 50 60 70 80 90 100 2003/04 2004/05 2005 ... between 2003 and 2008. 0 10 20 30 40 50 60 70 80 A B C D E F G Fishing vessel In te ra ct io ... is described under ‘Methods’. Tixier et al. 188 –10 –5 0 5 10 15 20 25 30 2003/04 2004/05 2005/06 ... economIc zone: an assessment of dePredatIon levels and InsIghts on PossIble mItIgatIon strategIes ... Paper Title:  Interactions of Patagonian toothfish fisheries with killer and sperm whales in the ... pods were involved in 81.3% of the interactions. Significant variations of interaction rates with ...

   Science Journal Paper : CCAMLR Science, Volume 17 (CCAMLR Science, Volume 17) : 179–195 : Author(s): Tixier, P., N. Gasco, G. Duhamel, M. Viviant, M. Authier and C. Guinet

10. Integrating Count Effort by Seasonally Correcting Animal Population Estimates (ICESCAPE): a method for estimating abundance and its uncertainty from count data using Adélie penguins as a case study

    Paper Title:  Integrating Count Effort by Seasonally Correcting Animal Population Estimates ... animal count data to a common reference point of breeding chronology for species with a complex temporal ... function of sampling availability. ICESCAPE (Integrating Count Effort by Seasonally Correcting Animal ... Integrating Count Effort by Seasonally Correcting Animal Population Estimates (ICESCAPE): a method ... IntegratIng Count effort by SeaSonally CorreCtIng anImal PoPulatIon eStImateS (ICeSCaPe): a method ... for eStImatIng abundanCe and ItS unCertaInty from Count data uSIng adélIe PenguInS aS a CaSe Study J. McKinlay ... Canada Abstract This work describes a parametric bootstrap model for standardising animal count data ... availability. ICESCAPE (Integrating Count Effort by Seasonally Correcting Animal Population Estimates ...

    Science Journal Paper : CCAMLR Science, Volume 17 (CCAMLR Science, Volume 17) : 213–227 : Author(s): McKinlay, J., C. Southwell and R. Trebilco

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