A neglected opportunity for bird conservation: The value of a perennial, semiarid agroecosystem in the Llanos de Ojuelos, central Mexico

Perennial, low-input, dry-farmed agroecosystems, especially those focused on fruit production, offer important opportunities to conserve biodiversity in semi-arid lands where fragmented natural habitats are unlikely to be restored. We studied the use of nopal orchards by birds and the effect of neighboring vegetation (shrubland, grassland, and annual rain-fed cropland) in the Llanos de Ojuelos, in the south-center of the Mexican Altiplano. Orchards were as rich as shrublands in terms of bird species, and richer than grasslands and croplands, and this did not depend on the adjacent habitat. Some bird species were more frequent in orchards and shrublands, but there was no typical orchard-shrubland bird assemblage, nor a grassland or cropland assemblage. Nopal orchards provided habitat for shrub-loving birds, and for birds typically found in grasslands of good condition, which are now uncommon in the area. Variation among orchards is not a function of the habitat to which they are adjacent, and it does not follow a geographical pattern; rather, it reflects the physical conditions (soil, rainfall of a particular year) and the idiosyncrasies of the owners regarding orchard and edge constitution and management. This work reaffirms that nopal orchards could be a valuable habitat for biodiversity conservation in this area.