Примеры использования Acoustic surveys на Английском языке и их переводы на Русский язык
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Other acoustic surveys in ccamlr waters 29.
General issues relevant to acoustic surveys in ccamlr waters.
It is important to quantify bias in both trawl and acoustic surveys.
This information could be provided through acoustic surveys and observations on board krill fishing vessels.
Data on Antarctic krill are available from both net and acoustic surveys.
Large-scale acoustic surveys have been conducted specifically to determine biomass in several CCAMLR statistical areas.
Fishery survey data including acoustic surveys.
It would be important to orient acoustic surveys aboard commercial vessels on data collection in relation to options paragraph 3.22(i)b.
Gunnari biomass andabundance indices from combining trawl and acoustic surveys;
Comparisons of results between trawl and acoustic surveys is a question of efficiency.
Its aggregating behaviour andsize makes it a suitable candidate for acoustic surveys.
Four basic sources of information were identified:net surveys, acoustic surveys, fisheries data and information from krill predators.
NORI was awaiting construction of a new deep-towed sonar system,which will be a key piece of equipment in acoustic surveys.
Decision rule to adjust catches up from the base Design acoustic surveys to be undertaken by fishing vessels.
The Convener of SG-ASAM clarified that the use of the dB difference method is recommended as part of the CAMLR standard method for scientific acoustic surveys.
She indicated the need to have acoustic surveys accompanied by net surveys more regularly within a year rather than a single survey in a year.
The Subgroup considered papers andpresentations outlining various methods for using krill fishing vessels to conduct acoustic surveys for Antarctic krill.
If this and target strength issues can be overcome then acoustic surveys may be more efficient than trawl surveys as they can provide greater spatial coverage in a shorter time span.
The two areas with contrasting levels of fishing should each have land-based predator monitoring, at-sea predator monitoring and acoustic surveys to assess ecological status.
The Working Group recalled that for biomass estimation from acoustic surveys, the important measure is the range of krill lengths in an associated biological sample, where the distribution between vessels was very similar.
The Working Group agreed that facilitating fisheries research that contributes towards development of FBM was important;e.g. requirements for fishing vessels to conduct acoustic surveys(paragraph 2.169), might necessitate careful consideration of temporal/seasonal catch limits.
It recognised that vessels which conduct acoustic surveys could be disadvantaged over other vessels that did not conduct such surveys, as they lost potential fishing time paragraph 2.39.
The calculations use conservative estimates of subarea biomass calculated as annual biomass estimates from local area acoustic surveys, scaled by the relevant estimate of subarea biomass from the CCAMLR-2000 Survey. .
Acoustic surveys may provide important information and the presenter discussed how to maximise the utility of research and fishing vessel acoustic data to support developing feedback management procedures.
WG-EMM-15/54 presented krill length-frequency distributions collected during the acoustic surveys that showed a strong year class in 2012 detectable as 25 mm cohort.
The Working Group noted the previous successful work to standardise survey requirements amongst CCAMLR Members, including developing standard methods for demersal fish trawl surveys(SC-CAMLR-XI,paragraph 3.20) and for acoustic surveys SC-CAMLR-XVII, paragraphs 5.4 to 5.14.
These included data from krill net sampling, krill acoustic surveys, CPR sampling, penguin foraging areas, seabird foraging tracking data, and East Antarctic pack-ice seal surveys. .
Marine mammal and seabird distribution andabundance 2.23 The Working Group discussed the recommendation by WS-SISO to consider the suggested design of a sampling regime to record air-breathing predators observed around krill vessels during fishing operations and during acoustic surveys carried out by the krill fishery(Annex 4, paragraphs 4.1 to 4.3), and how these data would progress the work of WG-EMM.
The meeting focused on the development of methodologies for acoustic surveys of icefish(Champsocephalus gunnari) and the review of the acoustic sampling protocols for krill(Euphausia superba) for use by CCAMLR-IPY projects.
Large-scale synoptic surveys have covered areas of the Southwest Atlantic and the Indian Ocean andthe most recent acoustic surveys(BROKE, CCAMLR-2000 and BROKE-West; see Table 1) have provided the largely comparable datasets that have been used by CCAMLR to set precautionary catch limits.