Survey : GEBL/R/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 06/11/1929 and 13/11/1929 on GBligh

Equipment used during this survey :

- Otter trawl Codend catch

Survey operations were undertaken on 11 stations

0 different species were caught on this survey

本次调查由Cefas（前身为渔业局）实施，作为CEFAS历史调查的一部分。自1902年以来，Cefas在英国周边海域（尤其是北海）进行了多次研究调查，收集了站点和生物数据。与当前的国际底拖网调查（IBTS）不同，调查捕获物并未系统性地以网格形式排列，而是广泛分布于北海南部和中部地区。由于该系列数据的长期性质，工具和方法并未实现标准化。调查在各个季节均有所进行。两次世界大战期间的数据缺失。在某些时期（如20世纪初），记录了捕获的所有物种，而在其他时期（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、鳎鱼和鳕鱼）。值得注意的是，某些调查针对特定物种（特别是比目鱼）。1929年6月11日至11月13日，在GBligh号上进行的调查中，使用了以下设备：海獭拖网和网囊捕获物。调查在11个站点进行，共捕获了0种不同的物种。