What causes the long-term decline of the Bewick's swan in the Netherlands?

The Netherlands are an important wintering area for menay northern breeding birds, including the Bewick's swan Cygnus bewickii, with up to 70% of the total population witering in the Netherlands. The Bewick's swan is a Natura 2000 target species and therefore the Netherlands have international responsibility to maintain a favourable conservation status of the species. During the past two decennia the number of Bewick's swans wintering in the Netherlands has been halved and its coservtaion status is now unfavourable.

Within this project we investigate a number of factors that may contribute to the decline of the Bewick's swan during various stages of the annual cycle. Ultimately, we aim to explain the causes of the negative population trend and give recommendations that policymakers can use to increase the conservation status of the species. To reach this goal, we will build an integrated population model that uses counts as well as resightings of individually marked birds to estimate demogarphic parameters. In addition, we wil use GPS-transmiters to track Bewick's swans during their migration. We will also investigate the possibility of a re-distribution of wintering birds as a cause for a apparent decline. Such a re-disribution is plausible given recent rapid changes in climate and land-use.


NIOO-KNAW, Vogeltrekstation, Sovon, IWWR-RUN

Financed by: 

Nederlands Polair Programma - NWO


Bart Nolet, Rascha Nuijten