Lesser Kestrel in urban SPAs: improving the conservation status of its habitat

Habitat loss associated with changes in land use, together with the intensification of agriculture, has lead to a decline in many species of invertebrates, and this in turn has lead to a reduction in populations of the Lesser Kestrel (Falco naumanni).One of the main drawbacks in promoting diversity and increasing the density of invertebrates is the lack of knowledge about their biology, ecological requirements and specific sampling methods. The aim of this project was to study the main feeding areas of the lesser kestrel in 3 urban SPAs in Extremadura (Spain), in order to study its habitat, the preferred invertebrates in its diet and their ecological requirements. The ultimate goal was to improve the conservation status of the lesser kestrel and its prey through habitat management.  In 2018, Terra Naturalis, carried out the following actions: 1) capture, marking and monitoring of individuals; 2) characterization of the species feeding habitat; 3) analysis of the composition of its diet; 4) ecological characterization of the main prey species and 5) analysis of chemical contaminants in infertile eggshells and invertebrates. 18 feeding areas were detected at a distance of 700 m-16 km from the colonies. In a number areas, the habitat around the colony was found to be unfavorable for the lesser kestrel. These areas were zones of harvested cereal, wastelands, grasslands, broom, thistles and scattered grasses. More than half of the prey identified in the diet were Orthoptera, representing 77% of the ingested biomass. These insects selected their suitable habitat on the basis of vegetation structure and the microclimate, showing preference for areas with greater diversity of plants and height heterogeneity.The results of the toxic substance analysis in eggshells and invertebrates were negative.

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