PFA assistant scientist Lina de Nijs executed the first phase of a study into the potential fecundity of female mackerel in the northeast Atlantic Ocean
The Pelagic Freezer-trawler Association’s (PFA) assistant scientist Lina de Nijs executed the first phase of a valuable study into the potential fecundity of female mackerel in the northeast Atlantic Ocean.
Fecundity is the natural capability to produce offspring, measured by the number of eggs per female fish.
Through this research, the PFA is contributing important information to the international triennial mackerel egg survey that is taking place this year from February until August. Under supervision and instruction by scientists from Wageningen Marine Research (WMR) and PFA Chief Science Officer Martin Pastoors, Lina worked onboard a PFA freezer-trawler during two trips. She managed to measure 2,220 mackerel of which 379 could be sampled for gonads because the fish were in the right stage. These samples will later be further analysed in the WMR laboratory.
This type of collaboration between science and the fishing sector provides important data and expands knowledge.
On the research Lina de Nijs said:
“Working on scientific research in a commercial fishing environment was another step in my steep learning curve as a junior fisheries scientist! I thoroughly enjoyed the close collaboration with the crew onboard who were very helpful and supportive. I look forward to learning more about the next steps in this research process.”
Lina’s journey in numbers:
- 45 days at sea;
- 49 hauls from which mackerels were sampled;
- 2,200 mackerels were examined;
- 379 samples were taken.
The ICES Working Group on Mackerel and Horse Mackerel Egg Surveys (WGMEGS) coordinates the mackerel and horse mackerel egg survey in the Northeast Atlantic (NEA) and the mackerel egg survey in the North Sea. The working group plans and reports on these surveys, with recent attention focused on the execution of the surveys given the increasing demands related to covering the expanding survey area as well as balanced fecundity sampling. WGMEGS also addresses data quality assurance in mackerel fecundity and total annual egg production estimation.
Currently, there are 3 surveys in place which are carried out triennially and deliver standing stock biomass (SSB) indices:
(1) the survey for the western and southern stock components of the NEA mackerel
stock, as well as for the western horse mackerel stock,
(2) the survey for the NEA mackerel North Sea stock component, and
(3) the survey for the southern horse mackerel stock.