2004-2012 Bishop et al. Occurrence of non-native sessile invertebrates on the English coast

Quality Control

Internal QA procedure at the Marine Biological Association by John Bishop at al. The dataset has not been put through the NBN record cleaner since many of the species are NNS of which distribution not widely known.

Method steps

1. Rapid Assessment Survey; Fixed Panels; Targeted Collections. At each marina the available floating pontoons were allocated between 3 surveyors. Each surveyor spent 1 hour searching their allocated area, examining and scraping pontoon sides, and examining any other substrates accessible from the surface e.g. ropes, buoys, fenders, kelps etc. All 34 target NNS presence/absence were noted and abundance estimated (using an abbreviated and adapted SACFORN scale where A=SA, F=CF, R=OR, N=N). The majority of species were determined on site. Any other potential NNS, unidentified specimens, those requiring microscopical examination for species confirmation, and specimens to substantiate significant findings were relaxed, preserved and examined later in the laboratory.

Covers surveys from marinas around the country, form the River Wyre near Blackpool on the West coast all the way down the coast, along the South and up the East coast to Newcastle-Upon-Tyne in the North East. Most surveys were undertaken on the South and South East coasts of England.