Abstract
This Technical Report has been prepared for Beatrice Offshore Windfarm Ltd (BOWL) as part of the Project Environmental Monitoring Programme (PEMP) required as part of the Section 36 Consent. This report describes the post-construction element of condition 27 of the PEMP in relation to cod spawning and satisfies condition 35 of BOWL’s Section 36 consent.
The report details the findings of the post-construction cod spawning survey undertaken between 1st March and 29th March 2021.
The objective of this survey was to characterise cod spawning within the BOWL site and adjacent areas in the Moray Firth. The overall survey methodology and survey equipment used replicated that previously agreed with Marine Scotland Science (MSS) and Marine Scotland Licensing and Operations Team (MS-LOT) for the undertaking of the preconstruction survey.
A total of 42 tows of 30 minutes duration were completed at 21 stations in two sampling trips between 1st March and 29th March 2021. Sampling was undertaken using a commercial rockhopper otter trawl with a 120 mm mesh cod-end, fitted with a 40 mm blinder. The length, sex and spawning condition of each cod was identified and recorded.
Cod were caught in 13 out of 42 tows undertaken, with a maximum of five individuals recorded at a single station (0T05, Trip 1). A total of 19 spawning cod were caught during the survey, 17 in Trip 1 and 2 in Trip 2. In line with the previous survey conducted in 2014, the number of cod by swept area (catch rate) were calculated using the net sensor data outputs.
During Trip 1 two stations had spawning cod catch rates considered to be indicative of the presence of a “spawning area”. During Trip 2, no stations recorded spawning cod catch rates indicative of the presence of a “spawning area”.
In addition, to cod, a total of 142,043 individuals of 30 commercial fish and shellfish species were caught in the survey. Haddock (Melanogrammus aeglefinus) and whiting (Merlangius merlangus) accounted for the majority of the total by-catch (82.2 % and 13.4 % respectively).
Comparison of the results of the pre- and post-construction surveys suggests that cod spawning occurred in the survey area pre-construction and that this continues to be the case post-construction. Both surveys found cod in relatively low numbers.