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 The
recently published study by a team of scientists from the
Royal Society for the Protection of Birds (RSPB)
and the BirdLife
European Division indicates alarming trends
showing that migratory bird species, flying between the
continents of Africa and Europe, suffered a sustained and
often severe population decline in the last 30 years. The
research also compared migrant and resident birds with similar
characteristics. It was evident, that trends of inter-continental
migrants were significantly more negative than those of
short-distance migrants or residents. This negative trend
appeared to be largely, although not entirely, due to declines
in species wintering in dry, open habitats in Africa.
There are many reasons for these dramatic
long-term population declines but ascertaining the cause
of any population decline is difficult. Different factors
or combinations of factors may be implicated for different
species. The reasons range from climate change, habitat
loss or deterioration on the wintering and/or breeding grounds,
loss of staging areas, hunting pressure to climate change.
The scientists are calling for more research into the causes
for the declines and to halt the loss of biodiversity.
The roll call of affected species in this
study is long. Fifty-four percent of 121 long-distant migratory
birds studied showed high rates of losses or had even become
extinct since 1970. Some of these long-distance migrants
covered by AEWA are: the Little Bittern (Lxobrychus
minutus), the Garganey (Anas
querquedula), the Corncrake (Crex
crex), the Black-winged Pratincole (Glareola
nordmanni), the Great Snipe (Gallinago
media) or the Sandwich Tern (Sterna
sandvicensis). Although AEWA together with its
Contracting Parties engages in a wide range of conservation
actions we agree with the authors that more research is
needed to better understand the causes of the decline in
migratory birds species.
Source: “Long-term
population declines in Afro-Palearctic migrant birds.”
Fiona J. Sanderson et al., 2006, Biological Conservation
131 (2006) 93-105
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