Distribution and numbers of wintering waterbirds in Sweden in 2015 and changes during the last fifty years

Leif Nilsson,Fredrik Haas

doi:10.34080/os.v26.21854

Abstract

The International Waterfowl Census started in Europe in 1967, in Sweden already in 1966. In Sweden, country-wide surveys of the inshore coastal areas were undertaken in 1971–1973, 2004 and 2015 in addition to the annual sample counts. In 2015, the entire coast between the Norwegian border and the northern part of the Stockholm archipelago was covered. The total estimate was 616,000 (excluding seaducks such as Long-tailed duck and scoters), a slight increase since 2004 and a large increase since 1971–1973. Long-term significant increase or little change was recorded for all species but the Longtailed Duck which decreased significantly. The distribution showed marked changes for several species, with larger proportions being found in the Baltic archipelagos in later years. In all EU the seaducks declined whereas most other species were stable or increased. In four diving ducks an increases in Sweden and other northern areas was balanced by decreasing numbers for countries to the south and southwest. Thus population changes in Sweden could be related to milder winters in the northern part of the wintering area.

Highlights

Coordinated midwinter counts of waterbirds have been undertaken on a European scale since January 1967, when the midwinter counts of the International Waterfowl Census (IWC) were started in a number of countries including Sweden (Atkinson-Willes 1969, Nilsson 1975, Gillisen et al 2002; see Nilsson 2008 for more references)
Soon realized that international cooperation was needed and the IWC was initiated by Wetlands International
The IWC aims to provide background information for international agreements relating to management of wetland birds such as the Ramsaar convention and AEWA (African Eurasian Waterfowl Agreement)

Summary

Introduction

Coordinated midwinter counts of waterbirds have been undertaken on a European scale since January 1967, when the midwinter counts of the International Waterfowl Census (IWC) were started in a number of countries including Sweden (Atkinson-Willes 1969, Nilsson 1975, Gillisen et al 2002; see Nilsson 2008 for more references). Sweden and some other countries had been running specific national programs for a number of years (AtkinsonWilles 1963, Owen et al 1986, Nilsson 1968, 1976). It was, soon realized that international cooperation was needed and the IWC was initiated by Wetlands International. The IWC aims to provide background information for international agreements relating to management of wetland birds such as the Ramsaar convention and AEWA (African Eurasian Waterfowl Agreement). For general information about IWC and the international results of the Midwinter Counts, see www.wetlands.org

Objectives

Methods

Findings

Conclusion