Search results
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Potential nursery areas for fish in the Prydz Bay region
Paper Title: Potential nursery areas for fish in the Prydz Bay region Abstract / Description: A ... survey with a fine-meshed midwater trawl in Prydz Bay in January/February 1991 indicated the potential ... for the shelf area of the Bay to be a nursery ground for nototheniid and channichthyid fish. Nearly ... antarcticum. This species was abundant (up to 9 100 were caught in a 30 minute haul) especially near the shelf ... PRYDZ BAY REGION R. Williams* * Abstract A survey with a fine-meshed midwater trawl in Prydz Bay ... in January/February 1991 indicated the potential for the shelf area of the Bay to be a nursery ... were caught in a 30 minute haul) especially near the shelf break. The dominant size class was of 45 mm ... nursery grounds were identified, the whole of the Prydz Bay shelf area could be considered a nursery ...
Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/8 (Selected Scientific Papers, SC-CAMLR-SSP/8) : 369–380 : Author(s): Williams, R.
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Attribtuion of acoustic echoes to squid in the south Atlantic
: During a research cruise of the British Antarctic Survey ship RRS James Clark Ross in February 1996, more ... than 2 000 individuals of the ommastrephid squid, Martialia hyadesi, were caught in a single haul made ... by a pelagic trawl near the Antarctic Polar Frontal Zone in CCAMLR Subarea 48.3. This paper describes ... the analysis of acoustic data gathered during this haul and a survey of the immediate vicinity, in ... Cambridge CB3 OET, United Kingdom Abstract During a research cruise of the British Antarctic Survey ship ... , Mavtialia hyadesi, were caught in a single haul made by a pelagic trawl near the Antarctic Polar Frontal ... haul and a survey of the immediate vicinity, in order to characterise an acoustic signature that may ... traversed by the net. The trawl was restricted to a single depth zone which reduced the potential number ...
Science Journal Paper : CCAMLR Science, Volume 5 (CCAMLR Science, Volume 5) : 259–271 : Author(s): Goss, C., P. Rodhouse, J.L. Watkins and A.S. Brierley
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Estimates of circumpolar abundance of Antarctic krill based on recent acoustic density measurements
estimates and others can be explained by a number of factors such as: an underestimation of the range or the ... acoustic biomass estimates; the possibility of a large, undetected krill population; and the overestimation ... and total precautionary limits are still likely to rise as a result of new surveys because the method ... used to calculate precautionary limits uses a value of 11% of the estimated pre-exploitation biomass ... explained by a number of factors such as: an underestimation of the range or the acoustic biomass estimates ... ; the possibility of a large, undetected krill population; and the overestimation of the demand for ... precautionary limits are still likely to rise as a result of new surveys because the method used to calculate ... precautionary limits uses a value of 11% of the estimated pre-exploitation biomass. Additionally, the current ...
Science Journal Paper : CCAMLR Science, Volume 7 (CCAMLR Science, Volume 7) : 87–99 : Author(s): Nicol, S., A.J. Constable and T. Pauly
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Distribution of krill (Euphausia superba Dana) catches in the South Shetlands and South Orkneys
South Orkneys Abstract / Description: A set of concentric zones of 20 km width was defined around ... . Krill catches in these zones are shown to have a consistent pattern in Subarea 48.1 but an unpredictable ... distribution in Subarea 48.2, probably as a result of more variable hydrographic conditions. About 50% of the ... fishery may have to increase by a factor of 2 or 3 before ratios of catch to consumption approach maximum ... DANA) CATCHES IN THE SOUTH SHETLANDS AND SOUTH ORKNEYS DJ. Agnew* Abstract A set of concentric ... the South Shetland and South Orkney Islands. Krill catches in these zones are shown to have a ... consistent pattern in Subarea 48.1 but an unpredictable distribution in Subarea 48.2, probably as a result ... by a factor of 2 or 3 before ratios of catch to consumption approach maximum sustainable levels, any ...
Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/9 (Selected Scientific Papers, SC-CAMLR-SSP/9) : 287–303 : Author(s): Agnew, D.J.
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Geographical differences in the condition, reproductive development, sex ratio and length distribution of Antarctic toothfish (Dissostichus mawsoni) from the Ross Sea, Antarctica (CCAMLR Subarea 88.1)
Subarea 88.1) Abstract / Description: A number of morphological and reproductive measurements made ... study indicate measurable differences in a number of indices from toothfish found on the Ross shelf ... population had a unimodallength distribution at a consistent peak over all sampling seasons in comparison ... with the southern group (in which the distribution was multimodal), showed a consistent and ... @clear.net.nz Abstract A number of morphological and reproductive measurements made seasonally on Antarctic ... differences in a number of indices from toothfish found on the Ross shelf proper, as distinct from those ... the northern part of the Ross Sea showed that this component of the population had a unimodal length ... distribution at a consistent peak over all sampling seasons in comparison with the southern group (in which ...
Science Journal Paper : CCAMLR Science, Volume 13 (CCAMLR Science, Volume 13) : 27–45 : Author(s): Fenaughty, J.M
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Optimization of survey sampling design in the detection of interannual variability and prey size selectivity in the diet of penguins
results of a survey of prey size in Adélie penguins, sampling designs intended for the detection of inter ... recommended and a required sampling protocol is suggested. A table of minimal numbers of penguins to be ... sampled as a function of number of sampling dates and magnitude of the variance component is given, under ... to the variance component of ‘penguin-within-dates’ obtained from a previous study in Bahía Esperanza ... . Marschoff and B. Gonzalez* Abstract Based on the preliminary results of a survey of prey size in Adelie ... each level in nested ANOV A designs. The optimal numbers of penguins and krill to be used in the ... detection of interannual variability in the parameters concerned are recommended and a required sampling ... protocol is suggested. A table of minimal numbers of penguins to be sampled as a function of number of ...
Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/7 (Selected Scientific Papers, SC-CAMLR-SSP/7) : 551–559 : Author(s): Marschoff, E. and B. Gonzalez
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Surface water circulation in krill fishing areas near the South Shetland Islands
with a drogue attached at a depth of 30 m to assess flow patterns at the depth range where krill tended ... buoy tracks, the surface circulation to the north of the South Shetlands shelf was described as a slow ... sluggish southwest current with a series of small-scale circular and semi-circular flows in the shelf ... . Between these counter-flowing currents a shear current was found in the slope region. The direct current ... oceanic waters to the north of the South Shetland Islands. Each buoy was deployed with a drogue attached ... at a depth of 30 m to assess flow patterns at the depth range where krill tended to be most abundant ... surface circulation to the north of the South Shetlands shelf was described as a slow sluggish southwest ... current with a series of small-scale circular and semi-circular flows in the shelf region, whereas the ...
Science Journal Paper : CCAMLR Science, Volume 3 (CCAMLR Science, Volume 3) : 125–136 : Author(s): Ichii, T. and M. Naganobu
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Estimation of effective sample size for catch-at-age and catch-at-length data using simulated data from the Dirichlet-multinomial distribution
distribution of catch-at-age or catch-at-length frequencies using a multinomial likelihood when there is extra ... , with marginal class probabilities generated using a simple age-structured model incorporating fishing ... , including a method based on an approximate profile maximum likelihood estimate (PMLE) of the D-M dispersion ... used for CCAMLR fisheries while the other is a new method. The methods that use haul-level frequencies ... catch- at-length frequencies using a multinomial likelihood when there is extra-multinomial ... marginal class probabilities generated using a simple age-structured model incorporating fishing ... frequencies, including a method based on an approximate profile maximum likelihood estimate (PMLE) of the D-M ... existing CV model used for CCAMLR fisheries while the other is a new method. The methods that use haul ...
Science Journal Paper : CCAMLR Science, Volume 15 (CCAMLR Science, Volume 15) : 115–138 : Author(s): Candy, S.G
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Length- and age-at-spawning of Antarctic toothfish (Dissostichus mawsoni) in the Ross Sea
Ross Sea spanning the 2000–2009 fishing seasons. A characterisation of the oocyte developmental cycle ... least a 6–12 month period, resulting in a developed group of oocytes accumulating at the final ... spawn at a younger age with an A 50% of 12.8 years (95% CI 11.9–14.0) or 120.4 cm (95% CI 114.8–126.7 ... ) by length. Evidence of skip-spawning was observed for females only and results in a flatter, right ... seasons. A characterisation of the oocyte developmental cycle of D. mawsoni shows that once development ... oocytes are then recruited into the vitellogenic phase over at least a 6–12 month period, resulting in a ... 133.2 cm (95% CI 130.9–135.7) by length. On average, males spawn at a younger age with an A50% of 12.8 ... observed for females only and results in a flatter, right-shifted ogive, increasing the functional ...
Science Journal Paper : CCAMLR Science, Volume 17 (CCAMLR Science, Volume 17) : 53–73 : Author(s): Parker, S.J. and P.J. Grimes
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Quantifying vessel performance in the CCAMLR tagging program: spatially and temporally controlled measures of tag-detection rates
temporally controlled measures of tag-detection rates Abstract / Description: A reliable commercial fish ... tagging program is critical to the successful management of a number of toothfish fisheries in Antarctica ... and temporal confounding. This paper presents a method that utilised most of the data while also ... controlling for spatial and temporal variables using a case-control study design, and uses this method to ... significant differences in the relative performance between vessels. In this analysis a case-control study ... the rest of the fleet. The scaled number of tags recaptured by a given vessel (case) is divided by ... the number of tags recaptured by a subset of the data (con- trol). Scaling is carried out for each ... A. Dunn National Institute of Water and Atmospheric Research (NIWA) Ltd Private Bag 14901 ...
Science Journal Paper : CCAMLR Science, Volume 20 (CCAMLR Science, Volume 20) : 73–80 : Author(s): Mormede, S. and A. Dunn