Habitat selection and breeding ecology of lesser kestrels Falco naumanni : implications for conservation
Through an understanding of the lesser kestrel Falco naumanni habitat preferences and
breeding ecology it is possible to determine the causes responsible for the species decline
and suggest conservation measures. This study was conducted in the Iberian Peninsula
during the lesser kestrel breeding period.
Unlike Spain, nest site availability was found to be a constraint for the lesser kestrels in
Portugal. The model for selection of buildings indicated that this species prefer buildings
with many roof and wall cavities and surrounded by extensive agriculture. In Portugal
and Spain, the villages selected by lesser kestrels had many old buildings and
monuments, were located in areas with few rivers, and low percentage cover of cereals,
olive groves and forest.
Habitat preferences were determined using telemetry and transect count data and the two
methods provided similar results. The effectiveness of radio tracking and visual sighting
transect data was compared and the costs and benefits of each technique were assessed.
Telemetry resulted in a larger number of significant differences between the habitats, but
the costs were higher. Telemetry also required more effort to set up and collect the data.
Transects were a cheaper technique but telemetry allowed areas with no roads to be
Findings indicate that lesser kestrel conservation is strongly dependent on the
maintenance of extensive agriculture characterised by a rotation of cereal and grazed
fallow. Abandonment of traditional agriculture and the recent changes in the agrienvironmental
programme support, which favour afforestation and intensification, are
jeopardising the future of cereal steppes and the lesser kestrel. Telemetry data indicated
that lesser kestrels prefer to forage close to the colony. In steppe habitats, the protection
of such foraging habitats within 3-km from the colonies could be an effective