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The swans are departing: they leave us as the weather turns more wintery.

 

The migration stop-over of Bewick’s swans in Estonia starts in October; halfway into November the last travellers have usually left. They can only reach the rhizomes of their pondweeds (Potamogeton) or stoneworts (Chara algae) in waters just over half a metre deep, and the changes in water level in autumn are quite large in our coastal waters. Wintering areas are the wetlands, polders or fields of the Netherlands, Great Britain, Ireland, Germany and Denmark. Only some twenty or thirty remain to winter together with the whooper swans in Estonian waters.

 

The departure of the whooper swans comes a few weeks later and passing swans from the north come by even in December. Whooper swans are common winterers in Estonia, mainly in northern Estonia and western Saaremaa. Depending on the severity of the winter and the ice conditions the number of winterers varies. In mild winters nearly a thousand whooper swans winter here, in severe conditions only one or two hundred.

 

The autumn migration passage of the best known swan, the mute swan, ends in December when the shallow sea bays start getting an ice cover. The largest gatherings are seen at the coasts of western and northern Estonia, and ever more by each year also at Lake Peipus where the migrants from north-east and east gather. Wintering areas are in the southern part of the Baltic - Sweden, Denmark, Poland, Germany, the Netherlands - but also Great Britain.

 

The most frequented wintering area for mute swans in Estonia is in north-eastern Saaremaa, in the Kudema bay, where more than a couple of thousand birds winter. Many  also winter around Saaremaa and at the coasts of the Gulf of Finland.