Data set title:
Plymouth Marine Laboratory Benthic Survey macrofauna abundance and biomass data set from four sites in the Western English Channel surveyed bimonthly
from 2008 to 2010 containing the data from the samples analysed as at December 2012.

Name of data file:
macrofauna_survey_2008-2010.csv

Data set creator(s) and institute(s):
Sarah Dashfield & Louise McNeill, Plymouth Marine Laboratory

Data set period:
Cawsand         50° 19.81' N, 04° 11.50' W   2008-07-18 to 2010-09-09
L4 (Hilmars Box)50° 13.30' N, 04° 11.40' W   2008-08-17 to 2009-07-08
Rame            50° 17.75' N, 04° 16.00' W   2008-06-04 to 2009-03-19
Eddystone       50° 11.54' N, 04° 16.89' W   2008-05-21 to 2008-07-23

Data set abstract:
Macrofaunal abundance and biomass data from 0.1m2 sediment samples collected from four subtidal sites around Plymouth between May 2008 and September 2010. The sites sampled were Cawsand (50° 19.81' N, 04° 11.50' W), L4 (Hilmars Box) (50° 13.30' N, 04° 11.40' W), Rame (50° 17.75' N, 04° 16.00' W) and Eddystone (50° 11.54' N, 04° 16.89' W). The entire data set has not yet been fully identified and contains the abundance and biomass data for samples analysed as at December 2012.

Sampling methodology and description of analytical techniques:
Bimonthly samples were collected at L4 (Hilmars Box) and Eddystone using a 0.1 m2 box corer.  Five reps were taken at random locations within 500m of anchoring site; the entire sample was elutriated and sieved through a 0.5 mm mesh; the residue was checked; gastropods were removed and placed in magnesium chloride for 24 hours; the macrofauna were preserved in 10% formalin. All fauna were counted and identified to lowest taxonomic level possible using compound and dissection microscopes. Wet weights of each taxon were recorded after blotting.
Bimonthly samples were collected at Cawsand using a 0.1 m2 Day Grab. Five reps were taken at random locations within 500m of anchoring site; the entire sample was elutriated and sieved though 0.5 mm mesh; the residue was checked; gastropods were removed and placed in magnesium chloride for 24 hours; the macrofauna were preserved in 10% formalin. All fauna were counted and identified to lowest taxonomic level possible using compound and dissection microscopes. Wet weights of each taxon were recorded after blotting.
Bimonthly samples were collected at Rame using a 0.1 m2 box corer.  Five reps were taken at random locations within 500m of anchoring site; the top oxic layers (20-30 cm) elutriated and sieved though 0.5 mm mesh; gastropods removed and placed in magnesium chloride for 24 hours; the remaining core was broken up on the sieve table and large macrofauna removed; the macrofauna preserved in 10% formalin.  All fauna were counted and identified to lowest taxonomic level possible using compound and dissection microscopes. Wet weights of each taxon were recorded after blotting.

Data quality comments:
Faunal identification was checked for consistency between the macrofaunal analysts. Species were identified using the most up to date literature available.  The accuracy of the balance is professionally checked annually.

Data usage:
It is essential for all users of these data to establish and maintain contact with the nominated current data originators as well as fully consulting the metadata. While not impinging on free data access, this ensures that this dataset is being used in the correct way, and any potential issues with the data are clarified. As more samples are identified, a proper dialogue with these local experts on the series may enable, where appropriate the most recent dataset to be used.