Azores bullfinch (Pyrrhula murina)
|Also known as:||priôlo, São Miguel Bullfinch|
|Size||Size: 17 cm (2)|
The Azores bullfinch is classified as Endangered (EN) on the IUCN Red List (1). Also included in the Portuguese Red Data Book and Annex I of the EU Wild Birds Directive (3).
The Azores bullfinch (Pyrrhula murina) has an exceedingly small range, being confined to the island of São Miguel in the Azores, Portugal (3). This medium-sized, plump bird has a dullish-coloured plumage, and is characterised by relatively short wings and a long tail. The wings, tail, face and cap are black, the back is brown, and the upper-tail coverts, nape of the neck and a distinctive wing bar are grey. Underparts are a pinkish-brown (2). Males are significantly larger than females (4) but the sexes are alike in terms of colour, although males have slightly pinker abdomens (2) (3). The contact call has been described as a plaintive ‘phew’ sound (2).
Found only in eastern São Miguel in the Azores archipelago, Portugal (3). Practically the whole population resides on slopes around Pica da Vara, although juveniles are regularly observed at Salto do Cavalo. Locally abundant in the 19th century, numbers of the Azores bullfinch began to rapidly decline after the 1920s, reaching a critically low number of just 30 to 40 pairs in the late 1970s. The most recent survey in 2004 estimated there to be a declining population of around 203 individuals (2).
Found from 300 to 800 metres above sea level, with seasonal variation in vegetation occupation. In summer (May to November), these birds choose bare ground with short vegetation (less than two metres high) and forest margins (3). Exotic vegetation such as plantations of Japanese Red Cedar (Cryptomeria japonica) and copses of Pittosporum undulatum, within 200 metres of native forest are also used during summer (2) (3). During winter (January to April) the Azores bullfinch appears to be limited to a 5.8 square kilometres area of native vegetation (2).
The diet of the Azores bullfinch comprises at least 37 different plants, and appears to show marked seasonal variation (3). In summer, birds take herbaceous seeds; in autumn, seeds of fleshy fruits; in winter, tree seeds and fern sporangia; and in spring, flower buds, fern sporangia, fern fronds and moss tips (4). The birds move from area to area following the fruiting availability of food plants (3).
Courting behaviour begins in May, extends through to early June, and involves bill caressing and twig displays (4). Breeding occurs from mid-June to late August (2). Clutch size is unknown (3) but studies suggest that two young are usually raised (4). Young fledge from mid-July and adults moult from September onwards (4).
The major causes of the decline of the Azores bullfinch are loss of native forest and large-scale invasion by exotic plants, some of which are now so widespread that they have become naturalised. In particular, laurel forest has been cut for grazing and agriculture, and lost due to afforestation by Japanese red cedar (Cryptomeria japonica) (3). Food shortages are now a cause for concern throughout the year, but most severe in late winter. The species has been left with an extremely small population and restricted range on just one island. The resulting reduced genetic variation may make it vulnerable to random environmental changes, and inbreeding may reduce reproductive output (2). In addition, predation by feral cats and rats is a potential problem, although their impact is currently unknown (2) (3).
The Azores bullfinch is protected under Portuguese law, and the area in which it is found in Pico da Vara has been designated a Natural Forest Reserve by the Regional Government of the Azores (2) (4). It was also designated a Special Protection Area by the Azorean Government under the EU Wild Birds Directive (4).
Although it is thought to be virtually impossible now to eradicate the exotic plants that threaten the species, efforts are being made to control them, whilst at the same time remaining patches of native vegetation are being restored and enlarged (3) via the planting of native species raised in nurseries, which began in early 1995 (4). An Action Plan for the species was published in 1996 and a current project aims to restore 300 hectares of laurel forest to increase suitable habitat and food availability for the species (2). However, native plants are often slow-growing and the positive effects of such efforts may only be seen in the long term (3).
An important five year project, headed by SPEA (BirdLife in Portugal) and the RSPB (BirdLife in the UK), is also underway to save this rare bird from extinction (5). The project aims to enlarge the current Special Protected Area (SPA), produce a site management plan, and implement a number of governmental policy measures that will benefit the Azores bullfinch habitat and help deal with the general problem of introduced plants (5). Most of the proposed management initiatives involve the further clearance of exotic invasive plant species and the planting of native species in the core area and buffer zones (6). In addition, the project aims to plant fruit tree orchards at lower altitudes to improve food availability in the end of the winter (one of the limiting factors presently affecting the Azores bullfinch population), and also to raise public awareness on the plight of this rare bird (6). This follows a short booklet on the species, its habitat, diet, feeding behaviour and conservation that has already been distributed to schools in São Miguel (2) (3). This is helping to raise awareness of the fragile position the bird is in, and hopefully encourage local support for the ongoing conservation measures needed to save this rare, endemic species.
For more information on the Azores bullfinch:
European Commission, Environment: Action Plan for the Azores Bullfinch (Pyrrhula murina):
Authenticated (19/07/2006) by Jose Tavares, Country Programmes Officer for Turkey, Portugal and Greece, The Royal Society for the Protection of Birds (RSPB).
- Afforestation: the establishment of forest by natural succession or by the planting of trees on land where they did not grow formerly.
- Coverts: small feathers that cover the areas where the primaries (wing feathers) attach to the wings and the retrices (tail feathers) attach to the rump.
- Endemic: a species or taxonomic group that is only found in one particular country or geographic area.
- Naturalisation: an exotic species that, once introduced into an area, has the capacity to adapt to the new environment, survive in competition with the endemic floral and faunal populations, reproduce itself and establish itself as a persistent part of the plant community.
IUCN Red List (May, 2011)
Birdlife International (January, 2006)
European Commission, Environment: Action Plan for the Azores Bullfinch (Pyrrhula murina) (April, 2006)
African Bird Club (April, 2006)
RSPB (July, 2006)
SPEA LIFE project: Azores bullfinch habitat recovery in Pico da Vara/Ribeira do Guilherme Special Protection Area: Summary of the project (July, 2006)