University of Southampton: kept busy with macrofauna processing

The team at the University of Southampton have spent the last few months busily working away processing samples for macro fauna abundance and biomass.

They have completed winter mudflat samples from the Tillingham site in Essex and Warton Sands in Morecambe Bay, and are a third of the way through salt marsh samples for Tillingham and winter mudflat samples for Abbots Hall. They’ve also completed the total organic carbon analysis for winter and summer Tillingham mudflat samples and Warton winter mud samples and are about to embark on a month long drive to process the remainder of the mud flat and salt marsh samples.A particle size analysis on the left over sediment from the TOC samples will be undertaken by the CBESS team at Cambridge and will hopefully commence in the next few weeks.

Core samples collected from Morecambe sites
Core samples collected from Morecambe sites

The first of the species composition data has shown some interesting comparisons between our East and West regions. It appears that the Essex mud sites are primarily composed of polychaetes such as Pygospio elegans, Hediste diversicolor, Eteone longa, and molluscs including Abra tenuis and Hydrobia ulvae, with no crustaceans being present. Morecambe however is a mix of crustaceans (Corophium volutator, Corophium arenarium and Bathyporeia pilosa) and molluscs (Macoma balthica and Hydrobia ulvae), with much fewer polychaetes present. Nematodes have been found at both locations, with Morecambe displaying the highest numbers.

 

In terms of overall number of individuals Morecambe wins. So far the sites have been less diverse in Morecambe compared to Essex, but the individual numbers have been high.

Southampton have also been working towards their commitment to investigate bioturbation, undertaking another winter campaign in Morecambe earlier this year, where 66 intact cores were collected from each of the three sites. These cores have been incubated back in their labs and the images and macrofauna are being processed by a team of students. These results will be communicated later in the year when all the samples and images have been fully analysed.