Azores Bullfinch

The Azores bullfinch, or São Miguel bullfinch, known locally as the priolo, is a passerine bird belonging to the true finch family. This plump bird, with its shorter wings and longer tail, is endemic to the island of São Miguel in the Azores. It measures 15–17 cm in length and weighs around 30 grams, with males being marginally larger than females. The plumage is more subdued than its Eurasian counterpart, featuring a black cap, face, wings, and tail, with the remainder of the body in shades of grey or pale grey-brown.

Identification Tips

Males and females are almost indistinguishable, though males may show a faint pinkish hue on the belly and flanks. The Azores bullfinch can be recognized by its melancholic, flute-like whistle, which serves as its contact call.

Habitat

This bird is found primarily in native laurisilva forests at elevations of 300–800 meters above sea level, particularly in the Serra da Tronqueira range and, seasonally, around Salto do Cavalo.

Distribution

The Azores bullfinch is confined to São Miguel Island in the Azores, with its presence notably absent from the western end of the island.

Behaviour

The species exhibits seasonal movements within its range, tracking the availability of food sources throughout the year.

Breeding

Breeding occurs from mid-June to late August. Nests are constructed within dense vegetation in the laurel forest, similar in structure to those of the Eurasian bullfinch, and are situated up to 3 meters off the ground. The exact clutch size remains unknown, and fledging of young birds takes place from mid-July, with adults molting from September.

Diet and Feeding

The Azores bullfinch's diet is predominantly herbivorous, consisting of seeds, fruits, flower buds, fern sporangia and fronds, moss tips, and some invertebrates. Native vegetation is preferred, and the lily of the valley tree plays a significant role in its diet, despite being considered an exotic species.

Conservation status

Classified as Vulnerable, the Azores bullfinch has experienced a decline in both population and range since the 1920s due to habitat destruction and invasive species. Current estimates suggest a population of around 775 individuals. Conservation efforts focus on protecting and restoring the laurel forest, with the entire range of the species designated as a Special Protection Area under European Union legislation.