Flapper Skate protection: NatureScot advice to the Scottish Government

Annex 3 Further survey work

High resolution multibeam survey is required to adequately discriminate potential egg-laying habitat in the Inner Sound (scale to be confirmed but ~15-35 km² requiring 6-12-days). An initial, broad survey area would be identified. Surveying areas of comparable bathymetry and aspect on the opposite side of the deep channel to the SW of the Crowlins should also be undertaken.

On the basis of preliminary analyses of the acoustic datasets (informed by existing DDV where available), targeted remote camera sampling would then be undertaken across areas of potentially suitable habitat and transitional sedimentary slope areas (3-4 days). A subset of any observations of eggs from the remote video work could then be investigated by divers to get a better estimate of numbers / density, as well as checking shallower habitats to confirm upper depths of egg habitat (~5-6 days).

We estimated 3-4-days for completion of remote camera work in the Inner Sound as part of the NatureScot Alba na Mara vessel requirements submission for 2021/2022.

A subset of any observations of eggs from the remote video work could then be investigated by divers to get a better estimate of numbers / density. Divers could also pursue any supplementary science questions as required (samples for genetics etc.) as well as checking shallower habitats in the vicinity to confirm upper egg-laying depths. Lower depth limits would rely on the remote camera sampling although the transition to a mixed sediment slope may occur in most parts below ~35 m.

Additional aspects could be built into the programme as required (e.g. in relation to the distribution and status of other PMF seabed habitats and proposed management areas off Scalpay, Longay and Pabay, and further investigation of the deep channel which may be used by adult skate).

Assuming resumption of survey work spring 2021, it would be possible to complete the camera work in July with diving in August / September and analysis and reporting over winter 2021/22.