FRV Alba Na Mara 1321A
Cruise plan
| Cruise Info. | |
| Ship name (ship code) | FRV Alba Na Mara (74NM) |
| Cruise identifier | 1321A |
| Cruise period | 2021-09-30 — 2021-10-12 |
| Status | Completed |
| Port of departure | Troon, United Kingdom |
| Port of return | Troon, United Kingdom |
| Purpose | Research |
| Objectives | Objectives
1. To determine the abundance, length and age of sandeels in the sediment in a region extending from the North-East Lewis pMPA to the North to the Sea of Hebrides pMPA to the South. 2. To collect and preserve samples of A. marinus, specifically i) all 0-group sandeels (size to be estimated from age/length keys of sampled catches) not required for age determination; ii) 100 age-1 individuals from each of the northerly and southerly sub-regions. 3. To determine the sex and maturity stage of all sandeels selected for ageing. 4. To collect sediment samples using a Day Grab. Procedure All required gear will be loaded onto the vessel on 24 September. Scientific staff will join the vessel on 29 September in Troon. Stations in and near the newly designated MPAs will be surveye. Stations will be sampled following the protocol established in 1999. At first a grab sample will be taken to confirm seabed suitability and then, a modified scallop dredge will be used to catch sandeels buried in the substrate at priority stations. The dredge will be deployed only if the ground is suitable and the risk of affecting other PMFs is low. Ideally three to five repeat tows will be conducted at each station although this may be reduced to a minimum of 2 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 (five, eight or ten depending on length strata, per half centimetre) will be taken for age determination (objective 1). All 0-group sandeels will be retained and frozen for later analysis. Sub-samples of 100 age-1 (size to be determined from age-length keys of sampled catches) A. marinus will be taken (objective 2). 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) (objective 3). |
| Chief scientist | Thomas Regnier (Marine Scotland Aberdeen Marine Laboratory) |
| Cruise programme |  (0.16 MB) |
| Ocean/sea areas | |
| General | Inner Seas off the West Coast of Scotland |
