Red-footed Booby (Sula sula)

Red-footed Booby

Description

The red-footed booby (Sula sula) is a large seabird of the booby family, Sulidae. Adults always have red feet, but the colour of the plumage varies. They are powerful and agile fliers, but they are clumsy in takeoffs and landings. They are found widely in the tropics, and breed colonially in coastal regions, especially islands. The species faces few natural or man-made threats, although its population is declining; it is considered to be a least-concern species by the International Union for Conservation of Nature (IUCN). The red-footed booby is the smallest member of the booby and gannet family at about 70 cm (28 in) in length and with a wingspan of up to 152 cm (60 in). The average weight of 490 adults from Christmas Island was 837 g (1.845 lb). It has red legs, and its bill and throat pouch are coloured pink and blue. This species has several morphs. In the white morph the plumage is mostly white (the head often tinged yellowish) and the flight feathers are black. The black-tailed white morph is similar, but with a black tail, and can easily be confused with the Nazca and masked boobies. The brown morph is overall brown. The white-tailed brown morph is similar, but has a white belly, rump, and tail. The white-headed and white-tailed brown morph has a mostly white body, tail and head, and brown wings and back. The morphs commonly breed together, but in most regions one or two morphs predominates; for example, at the Galápagos Islands, most belong to the brown morph, though the white morph also occurs.

Distribution And Habitat

The Red-footed Booby occurs throughout the worlds tropical (Oberle 2018) and subtropical oceans, and it is a widespread but very local year-round resident through the West Indies (Raffaele and others 1998). In Puerto Rico, large colonies of this species can be found at Mona and Monito islands, as well as near Culebra but in smaller numbers (Biaggi 1997, Kepler 1978, Oberle 2018). It is usually found around remote islands and cays well out at sea (Biaggi 1997, Raffaele and others 1998). The atlas fieldwork yielded a total of 20 records within 18 hexagons or 4 percent of the 479 total hexagons (see map). Of the 18 hexagons where this species was found, breeding met the atlas definition of confirmed in 28 percent (5) of the hexagons and possible in 17 percent (3), while the species was observed in 56 percent (10) of the hexagons but without evidence of breeding (see map). Red-footed Booby distribution. The map shows the highest breeding code by hexagon and overlaying the ecological life zones in Puerto Rico. Note: percentages may not total 100 due to rounding.

Breeding Habits

Previously published reports indicate that the Red-footed Booby breeds primarily from April to June, typically nests in colonies on remote small islands, and constructs a nest made of 141Red-footed Booby/Boba Patirrojatwigs which is usually placed in a tree or bush (Biaggi 1997, Raffaele and others 1998). Atlas results show that this species breeds mostly from February to April and during June, July, and October (see chart). Overall, the breeding activity peaks in July, and it takes place within the subtropical dry forest life zone (see chart). Results show that this species breeds in remote coastal islands within the subtropical dry forest life zone (100 percent of the hexagons) (see table and map).

Conservation

The Red-footed Booby is currently listed as a species of least concern by the IUCN (BirdLife International 2018). Locally, this species is not listed in any of the threatened categories of PRDNER and USFWS. In Puerto Rico, the Red- footed Booby has a protected habitat in land of 21 percent or 41 km2 of the total area covered by the hexagons where evidence of breeding was found for this species (192 km2).