The diet of the azores bullfinch Pyrrhula murina and floristic variation within its range Original Research Article

Information on plant-food resources is crucial for assisting the conservation of the Azores bullfinch Pyrrhula murina. This bird is confined to part of the native cloud forest in eastern S. Miguel (Azores), which is currently facing considerable changes. The diet is described and the time of food scarcity identified. Floristic variation in areas with and without birds is examined. The diet presents marked seasonal variations, from invertebrates and herbaceous and fleshy-fruit seeds in summer and autumn to fern sporangia, tree seeds, fern fronds and flower buds in winter and spring. The bird needs a mosaic of vegetation types, and seems heavily dependent on flower buds of Ilex perado at a time of food scarcity. Areas without birds have significantly lower densities of the food plants that are consumed during this period. Large-scale invasions of exotic species are threatening some of the forest mosaics. The implications for understanding the distribution and abundance of the Azores bullfinch are discussed and conservation measures proposed.