Data from: Wind farms affect the occurrence, abundance and population trends of small passerine birds: the case of the Dupont's lark

1.The assessment of the effects of wind farms on bird populations is
commonly based on collision fatality records. This could undervalue the
effect of wind farms on small-sized birds. We evaluate the effect of wind
turbines on occurrence, abundance and population trends of a threatened
small passerine species, the Dupont's lark Chersophilus duponti. To
our knowledge, this is one of the first studies addressing the effect of
wind farms on population trends using time series data from multiple wind
farms. 2.We estimated population trends by fitting a switching linear
trend model with the software TRIM (Trend & Indices for Monitoring
data). We used multiannual data surveys of five populations in the
presence of wind farms and nine in their absence (2008–2016 period).
Furthermore, we fitted a logistic and a negative binomial regression model
to test the effect of wind farm proximity on species occurrence and
abundance in 2016, respectively. We incorporated local connectivity and
habitat availability estimates in both models as predictors. 3.Results
showed a negative trend overall, but that was significantly more
regressive in the presence of wind farms: 21.0% versus 5.8% average annual
decline in the absence of wind farms. 4.Dupont's lark occurrence and
abundance in 2016 were negatively affected by measures of population
isolation and positively affected by the distance to wind farms. 5.These
results highlight the negative effect of isolation and wind farm proximity
on Dupont's lark population parameters. Taking into account the
metapopulation structure exhibited by the species in the study area, this
work established a 4.5 km threshold distance from wind farms, beyond which
Dupont's lark populations should be unaffected. 6.Synthesis and
applications. This work highlights the negative impact of wind farms on
small-sized birds and provides a 4.5 km threshold distance that should be
taken into account in the design of future wind energy projects. Moreover,
we suggest an analytical approach based on population trends, species
abundance and occurrence variation in relation to wind farms, useful for
the assessment of wind farm impacts on small-sized birds.