Effects of variable mean target strength on estimates of abundance: the case of Atlantic mackerel (Scomber scombrus)
Effects of variable mean target strength on estimates of abundance: the case of Atlantic mackerel (Scomber scombrus)
复制标题
可变平均目标强度对丰度估计的影响：以大西洋鲭鱼（鲭鱼）为例
DOI：
10.1093/icesjms/fsw212
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发表时间：
2017
期刊：
影响因子：
--
通讯作者：
P. Fernandes
中科院分区：
文献类型：
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作者：
B. Scoulding;S. Gastauer;D. MacLennan;Sascha M. M. Fässler;Phillip Copland;P. Fernandes
大西洋鲭鱼鲭鱼是一种小型中上层洄游鱼类，支持商业渔业。这些鱼类成群游动，可以用回声测深仪探测到，但对东北大西洋鱼类丰度的独立于渔业的估计没有考虑声学数据。平均目标强度（TS）的准确估计，目前限制回声集成调查提供有用的估计大西洋鲭鱼的丰度和分布。本研究提供TS估计原位鲭鱼从多频分裂波束回声测深仪测量。TS在18 kHz时为52.79 dB，在38 kHz时为59.60 dB，在120 kHz时为55.63 dB，在200 kHz时为53.58 dB，平均鲭鱼总长度为¼33.3 cm。这些值不同于目前假设的，这声学估计鲭鱼生物量的灵敏度周围的设得兰群岛，苏格兰，在2014年，TS的各种估计。置信限是使用地质统计学的覆盖范围和空间自相关会计。股票生物量，估计从38和200千赫的数据，相差10.5%，股票分布彼此相似，从一个独立的股票评估的估计。由于鲭鱼在38千赫的后向散射主要是从肉的回声，可能有相似之处，从鱼的鳔回声，并在200千赫的后向散射主要是相对稳定的回声从骨干，我们建议使用200千赫的数据估计大西洋鲭鱼生物量。
Atlantic mackerel Scomber scombrus is a small pelagic, migratory fish which supports commercial fisheries. These fish school and are detectable using echosounders, yet fishery-independent estimates of their abundance in the North East Atlantic do not consider acoustic data. Accurate estimates of mean target strength (TS) are presently limiting echo-integration surveys from providing useful estimates of Atlantic mackerel abundance and distribution. This study provides TS estimates for in situ mackerel from multi-frequency split-beam echosounder measurements. TS equals 52.79 dB at 18 kHz, 59.60 dB at 38 kHz, 55.63 dB at 120 kHz, and 53.58 dB at 200 kHz, for a mean mackerel total length¼33.3 cm. These values differ from those currently assumed for this the sensitivity of acoustically estimated mackerel biomass around the Shetland Islands, Scotland, in 2014, to various estimates of TS. Confidence limits were obtained using geostatistics accounting for coverage and spatial autocorrelation. Stock biomasses, estimated from 38 and 200 kHz data, differed by 10.5%, and stock distributions were similar to each other and to the estimates from an independent stock assessment. Because mackerel backscatter at 38 kHz is dominated by echoes from the flesh and may have similarities to echoes from fish with swimbladders, and backscatter at 200 kHz is dominated by relatively stable echoes from the backbone, we recommend using 200 kHz data for estimates of Atlantic mackerel biomass.