Survey : GEBL/H/1929 (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 15/05/1929 and 22/05/1929 on GBligh

Equipment used during this survey :

- Otter trawl Codend catch

Survey operations were undertaken on 19 stations

0 different species were caught on this survey

本项调查由Cefas（前身为渔业管理局）组织实施，作为CEFAS历史调查的一部分；该调查涵盖了自1902年以来在英国周边海域（尤其是北海）进行的科研调查中收集的站点和生物数据。与当前的国际底拖网调查（IBTS）不同，调查捕获物并非以网格系统进行系统布局，而是广泛分布于北海的南部和中部区域。由于数据系列具有长期性，故在调查过程中未实现器械和协议的标准化。调查在每个季节均有所进行。两次世界大战期间的数据缺失。在某些时期（例如20世纪初），捕获的所有物种均被记录，而在其他时期（例如1920年代至1930年代），仅对关键的商业物种（例如比目鱼、鳎鱼和鲭鱼）进行系统记录。值得注意的是，部分调查针对特定物种（特别是比目鱼）。1929年5月15日至22日，在GBligh号上进行了调查。此次调查所使用的设备包括：

- 海獭拖网
- 鱼网捕获物

调查操作在19个站点进行。此次调查共捕获0种不同的物种。