WTT Blog - Tagged with sea trout

Hopefully a few sea trout have found a bit of water (not round here mind) and are starting to return to our rivers at the moment. Fitting then to hand over the blog to Angus Lothian, a PhD student at Durham University (see his first blog here) to reflect on a new network for sea trout research.

Salmo trutta is a truly fascinating ‘species’, with such varying life history strategies and showing large phenotypic plasticity, exemplified by their key characteristic of partial-migration.  It is not yet fully known what drives partial-migration, with a component of a population of trout smolting and emigrating from rivers to sea, and the rest remaining river-resident.  Although the trout has often played second fiddle to Atlantic salmon, recent surges in the interest of trout ecology and biology, and in particular sea trout, has led to a rise in the number of scientists and PhD students researching this field.

I’ve just had the pleasure of hosting two MSc students from Queen Mary University of London (co-supervised with Dr Chris Eizaguirre), partly for the WTT Annual Get Together, and partly to undertake some fieldwork specifically for Charlotte Pike’s project. I alluded to their research projects in a former post and now I have the pleasure of handing over to them to update you.

Charlotte’s project focuses on the use of stable isotopes to determine the success of river restoration. I will be analysing samples from pre and post intervention works against an unimpacted control site on the same river to see how the restoration has affected the ‘architecture’ of the food web. Hopefully it should be more like the control! The intervention works have been carried out by the Ribble Rivers Trust at two locations; Bashall Brook and Towneley Hall. At Bashall Brook, a riparian zone has been created where banks of the river were previously bare; essentially livestock exclusion fencing now removes the impacts of grazing and poaching. This strip of vegetation acts as a buffer to reduce nutrient run-off from farmland, keeps the ground more stable and resilient to flood damage to reduce soil erosion, and provides necessary refuge for wildlife. At Towneley Hall, a partial weir removal and a rock pass re-instates the connectivity of the River Calder allowing fish to move between formerly fragmented habitats. These interventions have been conducted to improve the quality of the habitat at these two sites, and it’s my job to find out what changes have occurred as a result!