Search results
-
Data from recent trawl surveys in the vicinity of Heard Island and McDonald Islands (Division 58.5.2), reveal an unusual cohort structure in the mackerel icefish (Champsocephalus gunnari) population
Abstract: Surveys of mackerel icefish, Champsocephalus gunnari, was undertaken in Division 58.5.2 ... in the vicinity of Heard Island during September 2010 and April 2011, to provide information on the ... population dynamics of this species, and to provide a basis for an assessment of short-term annual yield in ... the 2011/2012 CCAMLR season. This paper provides a preliminary assessment of yield for the area of ...
Meeting Document : WG-FSA-11/22 : Author(s): D.C. Welsford (Australia)
-
ACCURACY OF BENTHIC INVERTEBRATE BY-CATCH IDENTIFICATION BY OBSERVERS OPERATING IN THE HEARD ISLAND AND MCDONALD ISLANDS PATAGONIAN TOOTHFISH LONGLINE FISHERY
Abstract: As a means of testing the accuracy of observer identifications and to provide ... Antarctic Division (AAD). Observers displayed a high level of accuracy (89%) in the identification of ... longline invertebrate by-catch. Common taxonomic errors included the misclassification of stylasterids ... training in the classification of cnidarians (stony corals, soft corals and stylasterids) and coral-like ...
Meeting Document : WG-FSA-09/23 : Author(s): T. Hibberd (Australia)
-
Interannual variation in the diet of the Antarctic prion Pachyptila desolata at South Georgia
Abstract: The diet of the Antarctic Prion Pachyptila desolata was examined using food samples ... was mainly crustaceans, with a small proportion of myctophid fish and trace amounts of cephalopods ... copepods, especially Rhincalanus gigas and Calanoides acutus, in two years of low krill abundance ... . Differences in the prey species taken and observations of foraging behaviour suggest that in years of low ...
Meeting Document : WG-EMM-97/12 : Author(s): Croxall, J.P., Edwards, T.M., Reid, K.
-
Conditions for the precise measurement of fish target strength in situ
Abstract: Conditions for precise measurement of in situ fish target strength (TS) are empirically ... studied and two indexes are introduced for this purpose. One is the number of fish in the effective ... reverberation volume which contributes echo formation at a certain instant and the other is the percentage of ... the multiple echoes which is derived from a residual of the single echo extraction. With the decrease ...
Meeting Document : WG-Krill-94/35 : Author(s): K. Sawada and M. Furusawa (Japan), N.J. Williamson (USA)
-
Estimation of krill (Euphausia superba) mortality and production rate in the Antarctic peninsula region
Peninsula from 26 December 1989 to 14 January 1990. Results were compared with data of an identical survey ... exceeded a factor of 35 times, while interannual variability between available surveys reached only a ... factor of 1.6 times. Krill mortality was calculated by linearized catch curve analysis and resulted a ... rate of Z=0.88 (1989/90) and Z=0.96 (1987/88). Production was estimated and resulted a P/B ratio of ...
Meeting Document : WG-KRILL-91/15 : Author(s): Delegation of Germany
-
Using effective sample sizes to evaluate the efficiency of length samples collected by at-sea observers in the krill fishery in Subarea 48.1
. Although analyses in the past have looked to the optimal design of the observer program, in terms of levels ... of coverage of vessels and hauls (e.g., Agnew et al., 2009; 2010), less attention have been focussed ... characterise how many krill are measured by observers, and for how many hauls. We then simulate the impact of ... combination (effective sample size). The median number of krill measured per haul was around 200 (range 0-652 ...
Meeting Document : WG-SAM-16/39 : Author(s): N. Kelly, S. Kawaguchi, P. Ziegler and D. Welsford
-
On interim distribution of the trigger level in the fishery for Euphausia superba in statistical Subareas 48.1, 48.2, 48.3 and 48.4
Abstract: This text is revised version of earlier presented by Ukraine document WG-EMM-16/56 ... . Taking into account the current state of krill fishery in Area 48 and other important factors, Ukraine ... proposes to upgrade the Conservation Measure 51-07 in order to redistribute the trigger level of catch in ... 620 000 tonnes between Subareas in Area 48 in a new percentage limits. This revision of CM 51-07 ...
Meeting Document : CCAMLR-XXXV/30 : Author(s): Delegation of Ukraine
-
Integrated analysis of the by-catch data in the Ross Sea toothfish fishery
Abstract: The indices of exploratory toothfish fishery in the Ross Sea for the period of 2008 ... hooks) and normalized target catch ratio. There was evidence of distinct differences in the mean (and ... the flag States, should be considered as the primary cause of the observed variability in the ... target catch ratio in the Ross Sea. The observed influence of the longline gear types (Autoline ...
Meeting Document : WG-FSA-16/13 Rev. 1 : Author(s): S. Kasatkina
-
Preliminary tag-recapture based population assessment of Antarctic toothfish in Subarea 48.4
Abstract: The stock of Antarctic toothfish (D. mawsoni) in CCAMLR subarea 48.4 is estimated from ... tagging returns to be 982 tonnes in 2018. Applying the CCAMLR agreed precautionary assumption of average ... biomass across the time series and harvest rate of γ = 0.038, implies a 2018/19 yield of 37 tonnes ... the 48.4 Antarctic toothfish as a separate stock. Based on the biological characteristics of the ...
Meeting Document : WG-FSA-18/26 : Author(s): T. Earl and A. Riley
-
Outline for year 3 of the 3-year longline survey to determine toothfish population connectivity between Subareas 48.2 and 48.4
third and final year of an agreed 3-year longline survey, in the wider context of connecting the ... understanding of Dissostichus spp population structures in this region, and improving available data on ... bathymetry and associated distributions of benthic bycatch species. This paper reiterates the key points of ... collection and two-year data analysis plan leading towards the development of a stock hypothesis for the ...
Meeting Document : WG-FSA-18/31 : Author(s): G. Robson, P. Hollyman and C. Darby