Abstract :
We estimated the breeding population size and assess the habitat relationships of Black-bellied
Sandgrouse in the Eastern Canary Islands (Fuerteventura, Lanzarote and La Graciosa, Spain) by
means of a survey based on 1,787 0.5-km line transects and distance sampling done in 2005 and
2006. The population comprised 2,906 individuals (90% CI: 2,363–3,562), which is much higher
than the numbers estimated in previous reports based on partial surveys, and constitutes 20% of
the total Spanish population. Sandgrouse in the Canaries are currently restricted to Fuerteventura,
where 70%of the population gathers in four areas that encompass just 16.7%of the island
and are largely within Special Protection Areas classified under the EU Birds Directive (except the
area of Tefia-Ampuyenta, first in absolute number of individuals). The environmental characteristics
that maximize the probability of occurrence of the sandgrouse in Fuerteventura (probability
5 0.196) are: treeless non-cultivated areas of sandy soils without bare bedrock, with a rock cover
less than 44%, located in non-coastal areas with an average terrain slope less than 27.5%, at more
than 400 m from the nearest urban area, with less than 795 m of dirt roads per 20 ha, with at least
0.9% of shrub cover and a NDVI index higher than 53. Sandgrouse were closer to human
settlements in midsummer than in March, perhaps being attracted to artificial pools surrounding
villages. Similar habitat characteristics exist in nearby Lanzarote, where the species could
hypothetically reach densities as high as 4–5 birds km2. Possible reasons for the absence of
sandgrouse in this island are discussed.
