Swans flood in!
Swan Lake has been completely transformed with the arrival of 75 new birds, including 24 cygnets, over the weekend! On Saturday night alone, 50 swans dropped down, in the biggest ‘swan-fall’ for seven years! As I write, 100 swans are swimming, preening, feeding, fighting and sleeping outside of my window, the sound of their calls almost deafening as birds re-unite and establish their territories.
The north-easterly winds and clear skies provided the perfect migratory conditions for them to push on to the UK and this weather looks set to continue for the next few days at least.
There are so many interesting characters to tell you about that I don’t quite know where to begin! I should probably start with the ‘divorcee’ Saruni who arrived yesterday with mate of two years, Sarune and four cygnets, having been spotted in northern Holland by Wim Tijsen last week!
Saruni, ringed 525, made heads turn two winters ago when she appeared to separate from old mate Sarindi. Both Saruni and Sarindi arrived with new partners that winter and had little to do with each other. It was only the second time in 50 years of research involving the study of 4,000 swan pairs, that a ‘divorce’ had been recorded at Slimbridge!
Bewick’s swans usually have very strong loyalties to one another, and tend to mate for life, although will re-pair if their partner dies. The longest partnership ever recorded was between Limonia and Laburnum who stayed together for 21 years! Grounds for Saruni and Sarindi’s divorce remain unclear although such an unusual event may be connected to a lack of breeding success. Perhaps this line of thought is plausible given that Saruni and Sarune have made it back with four strapping youngsters this winter.....
The arrival of Teapot and Teabag has restored our faith in long-term partnerships however, as they flew in for their sixteenth winter together!
So why do swans ‘mate for life’? Well, our research has shown that breeding success increases with the number of years that a pair has been together. This may be partly due to an improvement in co-operative parental care with experience and an improved ability to fight competitors! Over the years, The Teaparty has brought back 14 cygnets, some of which still visit the reserve.
The large number of cygnets now at the reserve certainly looks encouraging as we welcomed back old-timers Kirov and Kolguyev with their three cygnets, new birds Kaji and Kaju with two cygnets and Lucius and Aoki, also with two cygnets. Lucius is the father of Crinkly, a swan that beat the odds to return to Slimbridge for five years, despite having a deformity in her neck making her quite un-aerodynamic! Although we haven’t seen Crinkly for over two years, we are hoping that she has switched wintering sites after finding a mate and that she will return again one day.
