Conclusions
The population trends of the 15 breeding passerines analysed in
the Valbormida wind farm are similar to national trends; in particular
the increasing population trends found at national level have been
recorded also in the wind farm areas, although there was no possible
to define a population trend due to lack of data for some species.
It is also interesting to note that among the 15 species considered,
12 of them have a decreasing trend between 2008 and 2009;
in fact only Eurasian Blackcap, Common Chaffinch and Common
Chiffchaff do not show this trend, probably related to the construction
of the wind farm which probably have caused a disturbance
to nesting birdlife.
Considering these 12 species, 10 of them (the 83%) show a clear
population increase in the years following the construction of the
wind farm (2010 and 2011).
Most likely, this trend would presume that the species
“disturbed” by the wind farm construction return to the old nesting
sites when the construction phase is completed.
Overall it can be said that the construction of the analyzed wind
farm did not affect the conservation of the breeding passerine
populations.
These results confirmed other important studies, such as the
results obtained by Researchers from the Royal Society for the
Protection of Birds (RSPB), Scottish Natural Heritage and the
British Trust for Ornithology (BTO) [31]: looking at 10 bird species
at 18 wind farm sites in the UK, they established that wind
farms provoke minimal impact on birds from flying into rotating
turbines, even if the same study recognized that some bird
species suffer harm while wind farms are being built.
Moreover, due to their mobility, responsiveness to environmental
changes and sensitiveness to anthropogenic changes [32],
bird species are important ecological indicators for the conservation
of other kind of biodiversity [33]. Therefore the population
trends of the monitored nesting passerines constitute also a useful
tool for the assessment of the environmental and ecosystem health
[34] as well as species richness and endemism patterns [35].