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Some specific features of the USSR krill fishery and possibilities of applying fishery statistics to studies of krill biology and stocks
krill fishery, it is shown that the catch-per-haul variables are associated with the fishing regime of ... the vessel rather than with krill abundance in a certain area. During preparations for regular fishing ... operations very short hauls (under 15 minutes) are practised. Such fishing practice, together with ... -term behaviour patterns have an impact. All these factors limit the extent to which CPUE can be used in ...
Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/5 – Part I (Selected Scientific Papers, SC-CAMLR-SSP/5 – Part I) : 237–252 : Автор(ы): Dolzhenkov, V.N., T.G. Lubimova, R.R. Makarov, S.S. Parfenovich and V.A. Spiridonov
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The fishery for Patagonotothen brevicauda guntheri in CCAMLR Subarea 48.3
species. The small size of P.b. guntheri means that they can only be caught with net meshes so small that ... / Description: Fine-scale data supplied to CCAMLR for 1987/88 showed that the catches of P atagonotothen ... data and reports to the CCAMLR Working Group on Fish Stock Assessment indicated that this species was ... they would also catch undersized individuals of other, larger species. Survey results suggest that such ... . guntheri means that they can only be caught with net meshes so small that they would also catch undersized ... 1990). The catches from South Georgia that are reported to be of P.b. guntheri are not of that species ... that by-catches will be made it must be remembered that they are being made using gear designed for ... order to catch fish of this size it would be necessary to use a mesh considerable finer than that ...
Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/7 (Selected Scientific Papers, SC-CAMLR-SSP/7) : 275–283 : Автор(ы): Everson, I. and C. Mitchell
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Small scale krill surveys: simulations based on observed euphausiid distributions
that the coefficient of variation (CV) of mean krill density varies inversely with mean density, and is ... that with probability of Type I and Type II errors 0.1 and 0.2 respectively, about 100 transects would ... be required to detect changes of 40% in the mean if CVs are as high as those obtained in the ... on the power of surveys to reliably detect changes in mean density indicate that with probability ... , and do not generally have shapes that can be approximated by circles, the case that is usually ... swarms). Furthermore, Nicol (1986) shows that aggregations within an area may be elongated in one ... that are likely to be obtained in whole surveys of this nature, because of the very small scale of our ...
Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/8 (Selected Scientific Papers, SC-CAMLR-SSP/8) : 245–256 : Автор(ы): Agnew, D.J. and S. Nicol
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Can we use discriminant function analysis to sex penguins prior to calculating an index of a morphometric characteristic?
birds with greater than 80% success, the difference between the true and apparent mean is likely to be ... discriminant function with greater than 80% success may be used to derive statistically robust estimates of ... discriminant analysis can be used to determine the sex of individuals, it is only able to correctly sex a ... certain proportion of birds. Two overlapping normal distributions are used to show that there is a ... birds. Concern was expressed that it may be necessary to know the sex of birds with absolute accuracy ... , and that discriminant analysis may not be sufficient for this purpose (SC-CAMLR, 1991 - paragraphs ... 4.8 to 4.12). A suggestion was made that one way to avoid the problem of sex detennination would be ... that male and females should be combined when monitoring certain CEMP parameters, such as penguin ...
Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/9 (Selected Scientific Papers, SC-CAMLR-SSP/9) : 259–272 : Автор(ы): Agnew, D.J.
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Breeding numbers and success of Eudyptes penguins at Marion Island, and the influence of mass and time of arrival of adults
with that of females. Although both species had low masses on arrival after the El Niño Southern ... filholi) over 22 years, suggesting that overwintering conditions may influence the proportions of birds ... foraging range than rockhopper penguins when breeding, and may be more influenced at this stage by wider ... -scale environmental phenomena. For macaroni penguins, breeding success was significantly correlated with ... adults and chicks were marked with a harmless food colorant so that they would not be weighed a second ... correlated with that of females. Although both species had low masses on arrival after the El Niño Southern ... penguins at Marion Island from 1978/79 to 2004/05, and considers factors that may be influ- encing these ... were stronger for macaroni penguins, suggesting that, while breeding, this species may be more ...
Science Journal Paper : CCAMLR Science, Volume 13 (CCAMLR Science, Volume 13) : 175–190 : Автор(ы): Crawford, R.J.M., B.M. Dyer, J. Cooper and L.G. Underhill
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Characteristics of krill aggregations in the South Sandwich Islands subarea in January–February 2000
million tonnes. It was shown that the removal of biomass up to a recommended precautionary limit could be ... February 2000 it was observed that krill was present in non-aggregated and scattered forms, as well as in ... patterns of krill aggregations and distribution of krill biomass density were analysed with a view to ... detecting potential fishing grounds where the recommended precautionary catch limit could be taken. Such ... tonnes. It was shown that the removal of biomass up to a recommended precautionary limit could be ... aggregation characteristics. It should be noted that the improved technologies and methodologies of data ... , may be of interest to commercial fi shing. It was in these zones that the characteristics of krill ... 2000 are comparable with those observed for the krill fi shery in March 1983 (Table 4). It should be ...
Science Journal Paper : CCAMLR Science, Volume 9 (CCAMLR Science, Volume 9) : 145–164 : Автор(ы): Kasatkina, S.M., A.P. Malyshko, V.N. Shnar and O.A. Berezhinsky
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Precautionary spatial protection to facilitate the scientific study of habitats and communities under ice shelves in the context of recent, rapid, regional climate change
commercial fishing activities should not be permitted in these habitats, and suggests that areas under ... the loss of existing marine habitats and to the creation of new habitats, with consequent changes in ... existing ice shelves in Subareas 88.3, 48.1 and 48.5 should be preserved and protected for scientific study ... highlights why commercial fishing activities should not be permitted in these habitats, and suggests that ... - ed to be felt across the Antarctic as the ozone hole heals, with a predicted warming of about 3°C ... Antarctic shelf ecosystem, with high primary production during a short summer, are likely to be among the ... that form fol- lowing ice-shelf collapse will be susceptible to colonisation by species from areas ...
Science Journal Paper : CCAMLR Science, Volume 20 (CCAMLR Science, Volume 20) : 139–151 : Автор(ы): Trathan, P.N., S.M. Grant, V. Siegel and K.-H. Kock
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An assessment of the exploratory fishery for Dissostichus spp. on BANZARE Bank (CCAMLR Division 58.4.3b) based on fine-scale catch and effort data
analyses in other exploratory toothfish fisheries should be investigated, as this study indicates that ... depletion analysis of stratified catch and effort data indicate that there is strong evidence for depletion ... result, coupled with high estimated levels of illegal, unreported and unregulated (IUU) fishing, and ... evidence of poor recent recruitment, indicates that the stock is likely to have been overfished. Several ... period. Furthermore, IUU activity seems to be increasing, with catches estimated to have exceeded the ... likely to be low (Dunn et al., 2007; Welsford et al., 2007b), it is a rea- sonable assumption that each ... longlines failed to capture any D. mawsoni, compared with 485 long- lines (75% of total effort) that ... ( C ) lo ng lin es d ep lo ye d ) an d c at ch ( nu m be rs a nd w ei gh t fo r ...
Science Journal Paper : CCAMLR Science, Volume 15 (CCAMLR Science, Volume 15) : 55–78 : Автор(ы): McKinlay, J.P., D.C. Welsford, A.J. Constable and G.B. Nowara
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Abundance, size and maturity of krill (Euphausia superba) in the krill fishing ground of Subarea 48.1 during the 1990/91 austral summer
were generated, suggesting that hydrodynamic convergence might be responsible for accumulation of krill ... neritic and nearshore zones. This indicates that slope frontal features may be important for the formation ... in this zone. The total biomass over the survey area was estimated to be 1.59±0.45 million tonnes (95 ... + neritic + nearshore zones). Information from other studies indicated that krill biomass in this region had ... . This indicates that slope frontal features may be important for the formation of favourable conditions ... i-th zone Ni = number of transects in i-th zone t(Jl, a) = student's t-distribution with Jl ... ). This implies that the least favourable feeding environment might be responsible for the lower krill ... , comparing the two deeper zones (slope frontal and oceanic) the former zone may be more favourable in that ...
Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/9 (Selected Scientific Papers, SC-CAMLR-SSP/9) : 183–199 : Автор(ы): Ichii, T., H. Ishii and M. Naganobu
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Status of the coastal stocks of Dissostichus spp. in East Antarctica (Divisions 58.4.1 and 58.4.2)
participation in the fishery, with only some Small-scale Research Units (SSRUs, consisting of 10° longitude ... explores several methods for arriving at estimates of sustainable yields. Biological data suggest that ... there are two stocks in the area, one in Division 58.4.1 and one in Division 58.4.2, with the division ... between them being at about 90°E. The western stock may be centred around Prydz Bay, and appears to be of ... 58.4.2, with the division between them being at about 90°E. The western stock may be centred around ... critical that spatial variations in catch rate are accommodated. This is generally dealt with by spa ... - tially stratifying the data so that each area can be considered of constant biomass density. An overall ... for SSRUs that are cur- rently closed. Furthermore, limited research fish- ing (with a 10 tonne catch ...
Science Journal Paper : CCAMLR Science, Volume 16 (CCAMLR Science, Volume 16) : 71–100 : Автор(ы): Agnew, D.J., C. Edwards, R. Hillary, R. Mitchell and L.J. López Abellán
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