International Single Species Action Plan for the ... - AEWA

AEWA Technical Series No. 36
Land abandonment
Staging and wintering grounds
Importance: Medium
Abandonment of traditional agricultural land-management practices is a strong trend in many
countries of central and eastern Europe and Central Asia (e.g. Kazakhstan), and has been a
significant factor in parts of Fennoscandia. In some cases, such as the decline in mowing of
coastal and sub-alpine meadows at staging sites around the Baltic Sea, this may lead to
deterioration and loss of key Lesser White-fronted Geese feeding habitat due to the
progressive encroachment of shrubs and trees. However, the situation has improved
markedly in the Baltic region over the last ten years and most actual and potential staging
meadows are managed by grazing/mowing thanks to EU agri-environmental payments (J.
Markkola, pers. comm.). In Kazakhstan, the period from 1955 to 1990 was one of intensive
grain production and the littoral and near-littoral areas of all key lakes were regularly
cultivated and sown with grain. During the last 10 to 15 years, however, much of this land has
been abandoned and the distances to the main goose feeding areas have increased to 10-20 km
or more (S. Yerokhov, pers comm). In Sweden, hay cutting in Norbotten county has declined
from 200,000 ha in 1927 to about 1,000 ha nowadays. Most of the land formerly managed for
hay was located along the river-valley migration routes once used by Lesser White-fronted
Geese (M. Björkland, pers comm).
Overgrazing
Breeding grounds
Importance: Local
Over-grazing of tundra vegetation by semi-domestic Reindeer Rangifer tarandus may
threaten the quality of breeding habitat for the Fennoscandian population, though impacts
appear to vary from country to country. For example, data from the Swedish county of
Norbotten do not indicate any increase in overall reindeer numbers during the period when
the Lesser Whitefront population crash occurred (M. Björkland & S. Gylje, pers comm),
while in Finland, reindeer numbers doubled between the 1970s and 1990s and the adverse
effects on vegetation can clearly be demonstrated (T. Lehtiniemi/BirdLife Finland, pers.
comm.).
Pollution of wetlands/waterbodies
Staging and wintering grounds
Importance: Local
Point-source and/or diffuse pollution of wetlands and water bodies may be a locally important
cause of habitat degradation, but there are few if any documented cases that relate specifically
to Lesser White-fronted Geese.
(d) Potential genetic introgression of White-fronted Goose, Barnacle Goose
and/or Greylag Goose DNA into the wild Fennoscandian population from
captive-bred, supplemented/reintroduced birds.
Genetic studies have shown that a proportion of individuals within the captive breeding
populations used for the Finnish and Swedish supplementation/reintroduction programmes are
carrying DNA of other goose species, notably Greater White-fronted Goose 6 (Ruokonen et al.
2000, Ruokonen 2001, Ruokonen et al. 2007). The percentage of captive-reared birds
carrying alien genes in the Swedish captive stock was estimated at 36% (Ruokonen et al.
2007). Combining his breeding notes and genetic data, Tegelström assumed that the
6 Lesser White-fronted Goose individuals found to be carrying genes of Greylag Goose Anser anser have never
been used for reintroduction in Sweden (T. Larsson, pers comm).
International Single Species Action Plan for the Conservation of the Lesser White-fronted Goose 33