FRV Alba Na Mara 1821A
Cruise plan
| Cruise Info. | |
| Ship name (ship code) | FRV Alba Na Mara (74NM) |
| Cruise identifier | 1821A |
| Cruise period | 2021-12-06 — 2021-12-21 |
| Status | Completed |
| Port of departure | Leith, United Kingdom |
| Port of return | Fraserburgh, United Kingdom |
| Purpose | Research |
| Objectives | Objectives
1. To determine the abundance, length and age of sandeels in the sediment from regions east of the Firth of Forth and around Turbot bank. 2. To collect and preserve samples of A. marinus, from the different stations for further analyses and partners at UK-CEH. 3. To determine the sex and maturity stage of all sandeels selected for ageing. Procedure All required gear will be loaded onto the vessel on 3rd December, and scientists will be join the vessel on 5/6. December. Two regions of historical importance for sandeel fishing will be surveyed in the period 6 December - 21 December, weather permitting. In addition, new stations outside the closed area (stations 53-63) will be sampled to investigate the effect of fishing pressure on size and length distributions. A modified scallop dredge will be used to catch sandeels buried in the substrate at priority stations. Ideally five repeat tows will be conducted at each station although this may be reduced to a minimum of two if catch quantities are low or available time is limited. Dredge duration will be approximately ten minutes at a towing speed between two and three (ideally 2.5) knots. At each dredge station, all sandeels will be identified to species level, measured, and otoliths (5, 8 or 10 depending on length strata, per half centimetre) will be taken for age determination. All 0-group sandeels and some fish bycatch will be retained and frozen for later analysis. Sub-samples of 100 age-1 sandeel (size to be determined from age-length keys of sampled catches) A. marinus will be taken from the northerly (latitude > 57°N) and southerly (latitude < 57°N) sub-regions. Sandeels selected for ageing will be hand stripped and assigned a maturity stage based on a simple three-point scale (I = immature/indeterminate sex; MM= mature male; MF = mature female). Immature individuals will be individually frozen for further dissection and assigned to one of two stages (IM =Immature male or IF= Immature Female). All operations on board will be performed in compliance with the required regulations and guidance associated with the covid-19 pandemic. |
| Chief scientist | Thomas Regnier (Marine Scotland Aberdeen Marine Laboratory) |
| Cruise programme |  (0.35 MB) |
| Ocean/sea areas | |
| General | North Sea |
| Specific | East of Scotland |
