Примеры использования Krill abundance на Английском языке и их переводы на Русский язык
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There have been four large-scale acoustic surveys to measure krill abundance.
Krill abundance is actually estimated as a measure of biomass rather than as a count of the number of indivuals in the population.
The report documents survey methods and the krill abundance estimates for this year.
Based on this information and a set of equations,the echo signals will be converted to krill abundance.
Some Workshop participants noted particular enthusiasm for the krill abundance data layer derived from the data of Atkinson et al. 2004.
Data on krill abundance in the Ross Sea are available from Italian surveys and JARPA, and the report should be extended to discuss these sources of data.
The main purpose of these surveys was to gather data on krill abundance for catch limit estimates.
Unfortunately, no observer data are available from the very warm 2009 season,because the krill fishery moved away from South Georgia due to very low krill abundance.
It is important to maintain the current suite of time series to indicate krill abundance and the local processes that influence its variability.
The calendar also specified that krill abundance exhibited a step-change, and the model conditioning was conducted by assuming a 50% step-change in krill recruitment.
Day/night variability in krill backscatter andoptimal frequency for krill abundance estimation 2.14 Dr O.R.
The authors noted that there was no linkage between the krill abundance in the fishery and the subsequent larvae abundance; measuring the length distribution of the larvae was currently being conducted.
It is important that the index primarily comprises predators in locations where they respond to krill abundance(see also de la Mare and Constable, 2000);
Characterisation of the functional responses in these species to krill abundance is a very significant achievement, and provides direct evidence for the kind and extent of dependence of predators on krill availability.
The recruitment series for each predator was standardised for the age of recruitment so thatthe recruitment could be directly related to the krill abundance affecting recruitment.
The Working Group noted that because phenological changes can be a response to changes in krill abundance, further understanding of the factors driving phenology and their demographic consequences would be useful.
The last major review was in 2003(see SC-CAMLR-XXII) and included examination of the statistical power of the monitoring to detect any change, to detect change caused by fishing, andto estimate the response of indicators to local changes in krill abundance.
The Subgroup agreed that, in order touse the data collected along these nominated transects to investigate temporal variation in krill abundance, the transects should be sampled as frequently as possible during fishing Table 1.
Dr Constable cautioned that the available data on krill abundance may not support the conclusion for a decline in abundance in Area 48 given the CVs(which are often not reported) surrounding the historical estimates of krill abundance.
The Working Group recognised that, while the krill density data were from a local-scale survey,these data may well reflect changes in the variability in krill abundance over the feeding area of the population of southern right whales that calve in Brazil.
Since scientific information on winter krill abundance in all subareas in Area 48 is limited, the Working Group agreed that acoustic data collected by fishing vessels would help understand patterns of krill abundance in the areas fished.
WG-EMM-15/10 suggested that the experimental framework should focus on the relationships between oceanography, krill abundance and predator populations, and determine how krill fishing might modify these relationships.
The Working Group suggested that linking the analysis with acoustics data on the distribution of krill swarms collected from the krill fishing vessels would provide a means to expand the analyses to examine the relationship between fishery behaviour, krill abundance and catch rates.
The authors aim to estimate relative krill abundance from the annual CSVK surveys(carried out for 12 years) and undertake additional surveys with a design compatible with CCAMLR survey protocols to obtain an index of absolute krill abundance at a lower frequency.
The Working Group agreedwith these recommendations and also that, in order to use the data collected along these nominated transects to investigate temporal variation in krill abundance, the transects should be sampled as frequently as possible during the fishing season.
Early detection of systematic changes to krill abundance may be difficult with these relatively short and highly variable time series, but the probability of reliable detection will increase with the length of the time series, especially if the spatial replication is maintained.
The results are noteworthy because most CEMP indices are necessarily collected using land-based predators andthis study provides evidence of a significant correlation between krill abundance at South Georgia and reproductive success for a recovering cetacean species.
Comparison of the annual FPI with the krill biomass(from research surveys) and the combined standardised indices(CSIs) from CCAMLR Ecosystem Monitoring Program(CEMP) data suggests(at least qualitatively)some concordance between the performance of the fishery and krill abundance.
It was agreed that detailed information on survey design would be submitted with data from the first of these surveys to the next meetings of SG-ASAM(to consider the utility of the acoustic data for estimating relative and absolute krill abundance), WG-SAM(to assess the survey design, in particular the trade-offs between the primary goal of gathering information on cetaceans versus the secondary goal of gathering information on krill) and WG-EMM to review the results.
Spatial correlation of CEMP parameters 2.204 WG-EMM previously agreed that an analysis of spatial correlations between CEMP parameters was important for determining those parameters that might reflect local- andregional-scale changes in krill abundance SC-CAMLR-XXXI, Annex 6, paragraph 2.122.