Madeira storm-petrel (Oceanodroma castro)

Also known as: band-rumped storm petrel, band-rumped storm-petrel, Harcourt's petrel, Harcourt's storm-petrel, Hartcourt's petrel, Hartcourt's storm petrel, Hawaiian petrel, Madeira petrel, Madeiran petrel, Madeiran storm petrel
  
French: Pétrel de Castro
KingdomAnimalia
PhylumChordata
ClassAves
OrderProcellariiformes
FamilyHydrobatidae
GenusOceanodroma (1)
SizeLength: 19 - 21 cm (2)
Wingspan: 44 - 46 cm (2)
Weight29 - 56 g (2)

The Madeira storm-petrel is classified as Least Concern on the IUCN Red List (1).

The Madeira storm-petrel (Oceanodroma castro) is a rather large storm-petrel (3), a group of delicate seabirds which are recognised by their strongly hooked beak, pronounced tubular nostrils and steep forehead (4). Like other storm-petrels, the Madeira storm-petrel has overall blackish-brown plumage with a sharply-defined, narrow white band across the rump that extends slightly onto the under-tail coverts. This species also has a slightly paler, brownish-grey wing-bar across the upper-wing coverts. The tail is vaguely forked, the wings are fairly pointed and the legs are short (2) (5). 

The Madeira storm-petrel may be further identified by its undulating flight, consisting of shallow wingbeats interrupted with short glides on a zigzag trajectory (6). Due to its similarity to other storm-petrels, there is a degree of confusion regarding the taxonomy of this species. Until recently it was considered conspecific with Monteiro’s storm-petrel (Oceanodroma monteiroi) (7), and there is some evidence to suggest that there are several more species of storm-petrel in the Atlantic Ocean alone, meaning the Madeira storm-petrel may be further split into additional species (8).

The Madeira storm-petrel is found in the Pacific and eastern Atlantic Oceans. It breeds on remote islands of Japan, the Hawaiian Archipelago and the Galapagos, and on small eastern Atlantic islands off the coasts of Spain and Africa (5) (9).

This marine species is usually found far out at sea, feeding over deep, warm waters and rarely coming to land, except when breeding (9). It nests in burrows on remote islands, often in inaccessible places such as cliffs (5).

Returning to its colonies at night, the Madeira storm-petrel feeds during the day on a variety of small fish and squid. It feeds on the wing by dipping its bill into the water and seizing prey at the surface, often with the feet pattered over the water. It often feeds in groups around concentrations of prey, and may also feed on scraps discarded by other predatory seabirds (10). 

The Madeira storm-petrel returns to its breeding colonies around two months before egg laying takes place. The timing of breeding is highly variable, and some populations may have a distinct single breeding season, while others may breed in one of two seasons in the year (10). Once a suitable nesting site is found, breeding pairs excavate a burrow or remove debris that has fallen into an old burrow, using the bill to break up the substrate and the feet to push out excess soil. Breeding pairs often use the same nest year after year (5). 

A single egg is laid, and incubated for around 42 days. The male takes the first and longest stint of incubation, but thereafter both adults share the incubation duties in stints of around six days. The chick is brooded in the nest for around seven days, after which it may begin to explore its surrounds, often entering other nests for up to four days at a time. The chick is fed on regurgitated food, and upon the return of the adults it will call and nibble at the head and bill of the adult to receive the food (5). The chick fledges at 64 to 73 days, and individuals may live for up to 11 years (2).

Accurate data on the population size and conservation status of the Madeira storm-petrel has proved difficult to obtain, in part because of its nocturnal and burrow-nesting habits, which make surveys challenging (5). However, population declines have been observed in some areas, such as in Europe, where its breeding population underwent a moderate decline between 1970 and 1990 (11), and in Japan, where one colony was reduced from 25,000 pairs in the mid-1960s to only 800 pairs by 1994. The cause of these declines was likely to be a combination of human exploitation and habitat degradation (5). 

The Madeira storm-petrel has long been hunted for food. In the Eastern Atlantic, human predation on seabirds occurred until recently, especially in the Azores and on Saint Helena, and is likely continue to a small degree in Madeira. On large islands, habitat degradation has also severely reduced populations, meaning most now occur on small, isolated offshore islets. Continued development and degradation on the larger islands prevents recolonisation, thus leaving populations restricted to small patches of habitat with limited numbers of breeding sites. The development of artificial structures, such as buildings, also causes collisions, especially where there are bright lights to attract birds. This is thought to be a significant cause of juvenile mortality in the Madeira storm-petrel (5). 

On some islands, the Madeira storm-petrel is further threatened by predation by introduced mammals such as rats and cats (2) (5). Introduced sheep and goats may also trample burrows and, along with introduced rabbits, can overgraze vegetation, leading to erosion and landslides and causing burrows to collapse (5). 

A key conservation measure for the Madeira storm-petrel is the protection of the islands on which it breeds, as populations are unlikely to increase until this is undertaken. Some islands are already managed as reserves, including several islands in Hawaii, where introduced predators are controlled and development is restricted. Shielding man-made light sources on buildings would also benefit the Madeira storm-petrel by reducing juvenile mortality, and the provision of nesting boxes on Ascencion Island has improved the breeding success of this species (5).

In addition, the Madeira storm-petrel is currently listed as a Candidate Species by the U.S. Fish and Wildlife Service, meaning that its populations may receive future protection under the Endangered Species Act (12). 

Find out more about the Madeira storm-petrel and other birds:

Find out more about the conservation of albatrosses and petrels:

This information is awaiting authentication by a species expert, and will be updated as soon as possible. If you are able to help please contact:
arkive@wildscreen.org.uk

  1. IUCN Red List (March, 2011)
    http://www.iucnredlist.org/
  2. del Hoyo, J., Elliott, A. and Sargatal, J. (1992) Handbook of the Birds of the World. Volume 1: Ostrich to Ducks. Lynx Edicions, Barcelona.
  3. U.S. Geological Survey - Band-rumped storm-petrel (March, 2011)
    http://www.mbr-pwrc.usgs.gov/id/framlst/i1062id.html
  4. Perrins, C. (2003) The Encyclopedia of Birds. Oxford University Press, Oxford.
  5. Slotterback, J.W. (2002) Band-rumped storm-petrel (Oceanodroma castro). In: Poole, A. (Ed.) Birds of North America Online. Cornell Lab of Ornithology, Ithaca. Available at: 
    http://bna.birds.cornell.edu/bna/species/673a/articles/introduction
  6. Madeira Birdwatching - Madeiran storm-petrel (Oceanodroma castro) (March, 2011)
    http://www.madeirabirds.com/madeiran_storm_petrel_oceanodroma_castro
  7. Bolton, M., Smith, A.L., Gomez-Diaz, E., Friesen, V.L., Medeiros, R., Bried, J., Roscales J.L. and Furness, R.W. (2008) Monteiro's Storm-petrel Oceanodroma monteiroi: a new species from the Azores, Ibis: 150(4): 717-727.
  8. Ramos-Ordoñez, M.F., Rodríguez-Flores, C., Soberanes-González, C. and Arizmendi, M.C. (2010) Band-rumped storm-petrel (Oceanodroma castro). In: Schulenberg, T.S. (Ed.) Neotropical Birds Online. Cornell Lab of Ornithology, Ithaca. Available at:
    http://neotropical.birds.cornell.edu/portal/species/overview?p_p_spp=104956
  9. BirdLife International (March, 2011)
    http://www.birdlife.org/datazone/speciesfactsheet.php?id=3979
  10. Brooke, M. (2004) Albatrosses and Petrels across the World. Oxford University Press, Oxford.
  11. Burfield, I. and van Bommel, F. (2004) Birds in Europe: Population Estimates, Trends and Conservation Status. BirdLife International, Cambridge, UK.
  12. U.S. Fish and Wildlife Service - Band-rumped storm-petrel (March, 2011)
    http://ecos.fws.gov/speciesProfile/profile/speciesProfile.action?spcode=B08V