Modern distribution, new breeding and moulting places of the Mute Swan (<em>Cygnus olor</em> Gmelin) in the Leningrad region in 2005–2015

The article presents new data on nesting and moulting places of Mute Swan Cygnus olor Gmelin in the Leningrad region, observed in 2005–2015, describes the current status of its breeding and moulting places in the region, discovered in previous decades. An analysis of the spatial and landscape distribution of this species and the nature of its changes in recent years is given. The analysis shows that a significant increase in the number of breeding sites and moulting of the Mute Swan in the Leningrad region has not led to a marked increase in the local population. New places are populated primarily by solitary nesting pairs and small groups of moulting individuals, unlike some of the previously populated centers of mass reproduction and moult on Kurgalsky Peninsula and Seskar archipelago, where initially there was a high density of breeding and moulting birds. It may be characterised as a very low territorial expansion of the nesting area, but mainly as the colonization of empty loci in its old borders. Such type of colonization along with strong inter-seasonal local population dynamics depending on weather conditions, show the presence of climatical limit of the distribution of the this species in the region. Refs 58. Figs 6. Tables 1.