Oceanodroma castro
Silhouette: Richard Crossley · PhyloPic
In 3 days ~30% in a week ~50%
The band-rumped storm petrel, Madeiran storm petrel, or Harcourt's storm petrel (Hydrobates castro) is a species of storm petrel in the family Hydrobatidae. The band-rumped storm petrel is 19–21 cm (7.5–8.3 in) in length with a 43–46 cm (17–18 in) wingspan, and weighs 44–49 g (1.6–1.7 oz). It is mainly brownish black with an extensive white rump. Similar to Leach's storm petrel with the forked tail, long wings, but Leach's has a more deeply forked tail, a differently shaped (V-shaped or triangular) white rump, and a 'tern-like' flight, whereas the band-rumped storm-petrel has a more 'shearwater-like' flight.
The species breeds on islands in the warmer parts of the Atlantic and Pacific Oceans. These include the Berlengas (a few tens of kilometres off mainland Portugal), the Azores, Madeira, Canary Islands and Saint Helena in the Atlantic, and in the Pacific off eastern Japan, on Kauai, Hawaii, and on the Galápagos Islands. In 2016, the species was reported to have also started breeding on the Mauna Loa volcano on the island of Hawaii.
Birds nest in colonies close to the sea in rock crevices and females lay a single... Wikipedia →
Recording0:35
Spain · 2024
© Adrián Pina · iNaturalist · CC BY-NC 4.0
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Galápagos Islands | 🇪🇨 Ecuador | |
| 2 | Isla del Coco National Park | 🇨🇷 Costa Rica | |
| 3 | Cabo Blanco Absolute Nature Reserve | 🇨🇷 Costa Rica |
With luck
About 10% of wildlife watchers report a Band-rumped Storm-Petrel sighting in Galápagos Islands on a given day, based on 964 verified sightings from GBIF citizen-science data from 2019 to 2026. It is the 51st most-seen of the 114 birds we can rate there. Over three days the chance rises to about 30%, and over a week to about 50%, if each day is a fresh chance.
June
In that month about 20% of wildlife watchers report a Band-rumped Storm-Petrel in Galápagos Islands on a given day, against under 5% in September, the lowest month. That is one of Galápagos Islands's driest months, with almost no rain against 50 mm in March.
Between 10 am and 1 pm
Across all the parks we cover, that three-hour window holds the most Band-rumped Storm-Petrel sightings with a recorded time, and about 9 in 10 of them come between 6 am and 6 pm: it is a daytime animal.
Yes
Of the 3 parks where we can rate Band-rumped Storm-Petrel sightings, Galápagos Islands has the highest daily chance: about 10%. Next come Isla del Coco National Park (Costa Rica, under 5%) and Cabo Blanco Absolute Nature Reserve (Costa Rica, under 5%).
GBIF citizen-science records
It is estimated from how often the Band-rumped Storm-Petrel is recorded against all the birds logged in Galápagos Islands (964 verified sightings from 2019 to 2026), calibrated against known sighting rates. Figures are rounded to the nearest 10% because citizen-science data supports honest approximations, not decimals, and months with records from fewer than five people show "—". How it works.
