Foraging use of cultivated fields by the Houbara Bustard Chlamydotis undulata fuertaventurae Rothschild and Hartert, 1894 on Fuerteventura (Canary Islands)

Abstract

SummaryThe Houbara Bustard on Fuerteventura uses cultivated fields (gavias) as feeding sites, finding in these a high-level resource of easy access. A total of 521 visits were observed during this study, 81 to abandoned gavias, 139 to cultivated, and 301 to ploughed ones. This use was correlated with the total vegetation cover, as well as with cover by herbaceous plants and by alfalfa Medicago sativa. The relationship with invertebrate abundance was negative. Cultivated gavias were selected in relation to their alfalfa cover, abandoned gavias in relation to their herbaceous cover, and ploughed gavias were selected in relation to total vegetation cover, cover of herbaceous plants, Launaea arborescens and Salsola vermiculata cover, and vegetation height. Figs, present in ploughed gavias only, were a highly favoured food resource. Of the three study localities, Lajares was most visited by Houbaras (357 visits), followed by Triquivijate (105) and Tefía (59). This use was not correlated with the population of Houbaras in each locality but with the resources that were found in them. The gavias were used in all seasons of the year, mainly in summer, and less so in spring. In summer, use was correlated with herbaceous plant cover and associated to the presence of figs, and in winter with herbaceous cover; in autumn there was no overall selection for variables; in spring, selection was negative with respect to invertebrate availability. This predictable food resource is a real advantage for the maintenance of Houbara populations and contributes to the conservation of the species on Fuerteventura.