At the cannon netting session on 19th February the group took part in a shelduck research project which aims to identify the risks to migrating individuals from collisions with offshore wind farms. The research is being carried out by Ross Green from the BTO.
Shelduck don't perform the classical spring and autumn migrations between breeding and non-breeding sites like most migrant birds. Instead they migrate in summer – from mid-June to early August – to large estuaries to moult before moving on to wintering sites, which may or may not be near their breeding areas. All the known offshore migration routes pass through areas that may have offshore wind farms in future. The likelihood of interaction is therefore high, but it is unclear if the interactions will have any effect at the population scale, or an impact on migratory routes in the long term.
GPS data shows that these ducks mostly fly at night, and at heights above sea level that put them at risk of collision with turbine blades.
Isotopes in the feathers of shelduck may be site specific and so it is hoped that each moult site will have a unique chemical signature. Analysis of feather samples could help to identify the movements of shelduck.
Our group collected small fragments of secondary feathers at our cannon session and these will help the project by showing where our birds go.
GPS data has been unable to establish where birds go after they've moulted, so this feather analysis will help to fill that knowledge gap. This method is also considerably cheaper than GPS tracking.
Robin Pearson
