Survey : CLIO/7/1974 (part of CEFAS Historic surveys)

This survey was undertaken by Cefas as part of the CEFAS Historic surveys;

Station and biological data collected during research surveys carried out by
Cefas (formerly Directorate of Fisheries) in seas around the UK, mostly in the
North Sea, since 1902. The survey hauls are not laid out systematically as a
grid, as in current International Bottom Trawl Surveys (IBTS) and are widely
distributed over (especially) southern and central North Sea areas. Gears and
protocols were not standardised throughout, due to the long term nature of the
series. Surveys took place in each season. Data are lacking for the periods of
both World Wars. In some periods (e.g. the early 1900s), all species caught
were recorded, whereas in other periods (e.g. 1920s-30s), only the key
commercial species (e.g., Plaice, Sole and Cod) were recorded systematically.
Note that some surveys targeted particular species (notably Plaice).

Survey took place between 09/05/1974 and 30/05/1974 on Clione

Equipment used during this survey :

- Frame Trawl BoothBay Inverted 4 strops, 4 depressors, Fryma Net
- Granton 60mm Cod End No Chains Codend Catch

Survey operations were undertaken on 103 stations

32 different species were caught on this survey

此次调查由Cefas（前身为渔业管理局）负责实施，作为CEFAS历史调查的一部分。自1902年起，Cefas在英国周边海域（尤其是北海）进行了多项研究调查，收集了站点和生物数据。调查的渔获物并非按照系统化的网格排列，如当前的国际底拖网调查（IBTS）所采用的布局，而是在北海南部和中部区域广泛分布。由于该系列数据的长期性，设备和协议并未在整个调查过程中实现标准化。调查在每个季节都会进行。两次世界大战期间的数据缺失。在某些时期（例如20世纪初），记录了所有捕获的物种，而在其他时期（例如1920年代至1930年代），仅系统地记录了关键的商业物种（例如比目鱼、鳎鱼和鲭鱼）。值得注意的是，某些调查针对特定物种（特别是比目鱼）。1974年9月5日至5月30日，在Clione进行了调查。此次调查所使用的设备包括：
- Frame Trawl BoothBay Inverted 4 strops，4 depressors，Fryma网
- Granton 60mm无链鲭鱼网
调查在103个站点进行，共捕获了32种不同的物种。