page_title: European storm petrel
section_title: Breeding
hierarchical_section_title: European storm petrel / Behaviour / Breeding
caption_attribution_description: Deutsch&#x3a;&#32; Ei von Sturmschwalbe (Art). Jacques Perrin de Brichambaut.English&#x3a;&#32; Egg of Boyd's shearwater. Jacques Perrin de Brichambaut.Français&#x202f;&#x3a;&#32; Œuf de Océanite tempête. Jacques Perrin de Brichambaut.
context_page_description: The European storm petrel, British storm petrel, or just storm petrel is a seabird in the northern storm petrel family, Hydrobatidae. It is the only member of the genus Hydrobates. The small, square-tailed bird is entirely black except for a broad, white rump and a white band on the under wings, and it has a fluttering, bat-like flight. The large majority of the population breeds on islands off the coasts of Europe, with the greatest numbers in the Faroe Islands, United Kingdom, Ireland, and Iceland. The Mediterranean population is a separate subspecies, but is inseparable at sea from its Atlantic relatives; its strongholds are Filfla Island, Sicily, and the Balearic Islands.
  The storm petrel nests in crevices and burrows, sometimes shared with other seabirds or rabbits, and lays a single white egg, usually on bare soil. The adults share the lengthy incubation and both feed the chick, which is not normally brooded after the first week. This bird is strongly migratory, spending the Northern Hemisphere winter mainly off the coasts of South Africa and Namibia, with some birds stopping in the seas adjoining West Africa, and a few remaining near their Mediterranean breeding islands.
context_section_description: The storm petrel is sexually mature at age 4–5 years, with the Mediterranean subspecies typically breeding a year earlier than the Atlantic form. Breeding happens in colonies and normally begins in late May or June. Pairs have a repeated nocturnal display flight in which the male chases the female, the chase being accompanied by flight calls. Some near-adult birds may pair up and occupy a hole at the same time, prior to breeding in the following year.
  Storm petrels normally nest in crevices between or under rocks, or burrow in the soil. When they make their own tunnels, they loosen the earth with their bills and kick out the debris with their feet. The birds less commonly nest in walls, under buildings, or down rabbit burrows. Disused or occupied burrows of Atlantic puffins and Manx shearwaters are sometimes used, and the petrel pair may share a common entrance with those seabirds, rabbits, or other pairs of its own species. Where other occupants are present, the petrels dig a side burrow or use an existing low-roofed tunnel which the larger birds or rabbits cannot easily enter. Even so, puffins and shearwaters sometimes access and destroy nests, and adult petrels may be killed by their larger neighbours. Human-made plastic nesting tubes are readily used, and may provide protection against predators. Birds usually mate for life and use the same hole every year.
  The nest tunnel is 10–300 cm (3.9–118.1 in) long and 5–8 cm (2.0–3.1 in) across, with a slightly narrower entrance. The nest chamber is typically unlined, although pairs may bring in some grass, bracken, or seaweed. Although the storm petrel is generally not territorial when breeding, a pair defends the nest chamber itself after the eggs have been laid.
  The clutch is a single egg, usually pure white, sometimes with some reddish brown spots that soon disappear. The average size of the egg is 28 mm × 21 mm (1.10 in × 0.83 in), and it weighs 6.8 g (0.24 oz), of which 6% is shell. If an egg is lost early enough, a replacement may be laid on rare occasions. This is very unusual for tubenoses. The eggs are incubated by both parents for 38–50 days, the longer periods arising when the eggs have become chilled through adult absence. One adult typically spends three days at a time on the egg while its partner feeds at sea. The chicks are altricial and covered with silver-grey down, and are fed by both parents with their regurgitated oily stomach contents. The adults do not normally stay with the chick after the first week, visiting only to bring food. After about 50 days, the chicks are fed less regularly, sometimes with gaps of several days, and the parents may stop visiting completely shortly before the chick leaves the nest. The chicks fledge about 56–86 days after hatching, and receive no parental support after leaving the nest hole.
  Tubenoses have smaller egg clutches and much longer and more variable incubation and fledging times than passerines with similarly sized eggs, resembling swifts in these developmental factors. Tubenoses and swifts have generally secure nest sites, but their food sources are unreliable, whereas passerines are vulnerable in the nest but food is usually plentiful. In the particular case of the storm petrel, it has a body temperature perhaps 3 °C lower than other small birds, and this may also contribute to the lengthy incubation.
  The adult petrel's annual death rate is 12–13%, and the typical life span is 11 years. Longevity records established from bird ringing recoveries include a bird aged 31 years 11 months 9 days, and another aged more than 33 years.
caption: Egg of European storm petrel
   (coll.MHNT)
exif: {"Image ImageDescription": "Hydrobates pelagicus MHNT ZOO 2010 11 42 - Ile Calseraigne", "Image Make": "NIKON CORPORATION", "Image Model": "NIKON D800E", "Image Orientation": "Horizontal (normal)", "Image XResolution": "300", "Image YResolution": "300", "Image ResolutionUnit": "Pixels/Inch", "Image Software": "Adobe Photoshop CC (Windows)", "Image DateTime": "2017:05:20 08:25:43", "Image Artist": "Didier Descouens", "Image ExifOffset": "2428", "Image XPTitle": "[72, 0, 121, 0, 100, 0, 114, 0, 111, 0, 98, 0, 97, 0, 116, 0, 101, 0, 115, 0, ... ]", "Image XPAuthor": "Didier Descouens", "Image XPKeywords": "[77, 0, 117, 0, 115, 0, 233, 0, 117, 0, 109, 0, 32, 0, 100, 0, 101, 0, 32, 0, ... ]", "Image Padding": "[]", "Thumbnail Compression": "JPEG (old-style)", "Thumbnail XResolution": "72", "Thumbnail YResolution": "72", "Thumbnail ResolutionUnit": "Pixels/Inch", "Thumbnail JPEGInterchangeFormat": "5534", "Thumbnail JPEGInterchangeFormatLength": "2742", "EXIF ExposureTime": "1/60", "EXIF FNumber": "20", "EXIF ExposureProgram": "Manual", "EXIF ISOSpeedRatings": "100", "EXIF SensitivityType": "Recommended Exposure Index", "EXIF ExifVersion": "0221", "EXIF DateTimeOriginal": "2017:05:03 15:01:50", "EXIF DateTimeDigitized": "2017:05:03 15:01:50", "EXIF ShutterSpeedValue": "5906891/1000000", "EXIF ApertureValue": "540241/62500", "EXIF ExposureBiasValue": "-2/3", "EXIF MaxApertureValue": "7/2", "EXIF MeteringMode": "CenterWeightedAverage", "EXIF LightSource": "Unknown", "EXIF Flash": "Flash did not fire, compulsory flash mode", "EXIF FocalLength": "105", "EXIF SubSecTime": "80", "EXIF SubSecTimeOriginal": "80", "EXIF SubSecTimeDigitized": "80", "EXIF ColorSpace": "Uncalibrated", "EXIF ExifImageWidth": "2902", "EXIF ExifImageLength": "3083", "EXIF FocalPlaneXResolution": "16780511/8192", "EXIF FocalPlaneYResolution": "16780511/8192", "EXIF FocalPlaneResolutionUnit": "3", "EXIF SensingMethod": "One-chip color area", "EXIF FileSource": "Digital Camera", "EXIF SceneType": "Directly Photographed", "EXIF CVAPattern": "[2, 0, 2, 0, 0, 1, 1, 2]", "EXIF CustomRendered": "Normal", "EXIF ExposureMode": "Manual Exposure", "EXIF WhiteBalance": "Auto", "EXIF DigitalZoomRatio": "1", "EXIF FocalLengthIn35mmFilm": "105", "EXIF SceneCaptureType": "Standard", "EXIF GainControl": "None", "EXIF Contrast": "Normal", "EXIF Saturation": "Normal", "EXIF Sharpness": "Normal", "EXIF SubjectDistanceRange": "0", "EXIF BodySerialNumber": "6011792", "EXIF LensSpecification": "[105, 105, 14/5, 14/5]", "EXIF LensModel": "105.0 mm f/2.8", "EXIF Padding": "[]"}