Old Reunions!
This weekend, hundreds of swan enthusiasts will be heading out to wetland sites and other swan hotspots across Europe to take part in an international age census of Bewick’s swans. Their main task, aside from trying to stay warm (!), will be to determine the number of cygnets and adults arriving at wintering sites in north-west Europe. This valuable information will enable us to assess whether or not the Northwest European population has had a good breeding season. Early indications from ornithologists in different countries (as reported by our human swan Sacha Dench) suggest that there are low numbers of cygnets in flocks this autumn so it will be interesting to see whether the census reveals this to be the case for the population as a whole.
Annual assessments of breeding success and survival rates provide important data which can help us to explain population trends. Our most recent research suggests that there has been no sudden drop in cygnet numbers that could explain the worrying population decline in the Bewick’s swan. The count is co-ordinated by Dutch ornithologists Wim Tijsen and Jan Beekman.
As temperatures have dropped, more swans have arrived with up to 90 attending the 4pm swan feeds at Slimbridge every day. This week Steve Heaven, our swan research assistant, has reported some nice reunions amongst our Bewick's at Slimbridge. Last year two well known swans, Kaji and Lucius Two, sadly arrived without their long-term mates but this year they have refound their mates and Kaji has arrived back with Ponting and Lucius Two is back with Aoki.
We were also pleased to see long term pair Riddler and Riddles reunited last night. When Riddler arrived at WWT Slimbridge a week ago without Riddles we were a little worried so we were pleased to see her arrive safely.
Such temporary splits are a relatively rare occurrence. Where possible, Bewick’s swans tend to have strong long-term partnerships - our longest pairing recorded at Slimbridge was between a pair called Limonia and Laburnum who were together for 21 years! Fortunately, the swans tend to have great site fidelity and so pairs that are accidentally separated during migration are sometimes able to find each other again, whether it be at wintering, staging or breeding sites.
Many more swans are on their way to the UK with up to 3,000 expected to arrive on the Ouse Washes and 300 at Slimbridge during the course of the winter. Thousands remain further east - 1,200 Bewick’s swans were recorded by the Flight of the Swans team and ornithologist Heiko Rebling at Dohren in Germany last week!
