Monteiros Storm-petrel (Oceanodroma monteiroi)

Monteiros Storm-petrel

[order] PROCELLARIIFORMES | [family] Hydrobatidae | [latin] Oceanodroma monteiroi | [authority] Bolton et al., 2008 | [UK] Monteiros Storm-petrel | [FR] Guit-guit brillant | [DE] Not found | [ES] Not found | [NL] Monteiro Stomrvogeltje


Genus Species subspecies Region Range
Oceanodroma monteiroi AO Azores


Storm-petrels are rather small and often dark colored tubenoses with a world wide distribution. All have fine black bills with very pronounced tubes. Storm Petrels are separated in two groups: the long legged, Southern Hemisphere birds subfamily Oceanitinae and the shorter legged species of more northern seas the subfamily Hydrobatinae. The first groups shows more morphological differences than the second. The genera are characterised on colour patterns, the condition of the nasal tubes, tail shape, structure of claws and proportions of the leg bones. The genus Oceanodroma consists of medium-sized petrels; plumage dark or greyish, often with pale rumps; tail more or less forked; tarsus short , middle toe with claw and scutellate; claws narrow.

Physical charateristics

Iris dark brown; bill, legs and feet black. Entire head, mantle, scapulars, back and upper rump and upper tail sooty brown-black. Nape, mantle and scapulars, back and upper rump with grey wash in good light. Longest scapulars thinly edged very pale grey. Upper tail coverts white (white feather shafts) forming a white rump band c. 15 mm wide in the centre and c. 20 mm wide at the sides. Lower 10 mm of upper tail coverts tipped black, concolorous with upper tail. Bases of outer three tail feathers white, extending 33 mm from feather base on outmost tail feather. Underparts: Chin and throat slightly paler than upper headparts. Breast, belly, upper flanks, central undertail coverts noticeably browner than upperparts. Lower flanks and bases of outer undertail coverts white, forming a contiguous white band with rump, so the white rump ?wraps around’ the flanks, but not joining ventrally. Underside of tail feathers brown-black (very similar to underparts) with silvery sheen. Undertail coverts extending almost to tail tip centrally. Wing: Lesser coverts, carpal coverts, primary coverts, primaries and secondaries uniformly sooty brownblack Noticeable Light-Drab diagonal wing bar extending from tertials (and inner secondary), across the greater and median coverts, to the outer lesser coverts, almost reaching the leading edge of the wing. The outer three greater coverts have outer lower edge concolorous with the primary coverts. It was not possible to carry out a detailed examination of the underwing, but it appeared wholly dark, similar in colour to underparts.

wingspan min.: 74 cm wingspan max.: 82 cm
size min.: 16 cm size max.: 19 cm
incubation min.: 0 days incubation max.: 0 days
fledging min.: 0 days fledging max.: 0 days
broods: 0   eggs min.: 0  
      eggs max.: 0  


Atlantic Ocean : Azores. Monteiro’s Storm-petrel is known only from the Azores islands


Pelagic, but seems to stay around the Azores all year


This species breeds during the ‘hot season’; females lay eggs between May and early June, incubating a single egg until as late as early August, with the first chicks hatching in early June and fledging in early October

Feeding habits

Its diet is poorly known, but thought to consist of small fish and squid, and it generally feeds on prey of a higher tropic level than O. castro


This newly-split species is listed as Vulnerable as is has a very small population which is restricted to breeding on just two islets. It is therefore highly susceptible to stochastic events, and remains at risk of mammalian introductions.
Threats include high predation rates by Long-eared Owls Asio otus that are resident in the Azores; up to 40 adults are killed in some seasons. A vagrant Short-eared Owl Asio flammeus heavily impacted the population on one islet during the winter of 2002-2003. Both breeding islets are curently free of ground predators, but their close proximity to Graciosa and the large numbers of visitors to one islet in the summer means that the introduction of rodents is a continuing threat. Both islets lie within 2 km of the main shipping route for large passenger ferries and container ships docking on Graciosa. A cargo ship containing livestock ran aground on one of the breeding islets in 2000, leading to concerns over pollution and rodents escaping ashore.
Monteiros Storm-petrel status Vulnerable


The distribution of Monteiro’s Storm-petrel outside the breeding season is currently unknown, although the capture of two individuals on Praia Islet in late October and a further individual on Vila Islet in mid November suggests that it remains in the vicinity of the breeding grounds, rather than dispersing into the western Atlantic, as does the Madeiran Storm-petrel.

Distribution map

Monteiros Storm-petrel distribution range map

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