All birds/Sulidae/Masked Booby
AI reconstruction of Masked Booby (Sula dactylatra)AI

AI reconstruction created with Nano Banana 2 · 1K, grounded in the profile’s documented taxonomy, habitat, natural-history sources, and an open-license visual reference when available. It is an interpretive image, not documentary evidence. Image policy

Masked Booby (Sula dactylatra)
Verified source photographR VasconcellosCC-BY · View source
PRB-0184Suliformes

Masked Booby

Bobo Enmascarado

Sula dactylatra

Native / natural occurrenceIUCN LC · Least Concern

The masked booby (Sula dactylatra), also called the masked gannet or the blue-faced booby, is a large seabird of the booby and gannet family, Sulidae. First described by the French naturalist René-Primevère Lesson in 1831, the masked booby is one of six species of booby in the genus Sula. It has a typical sulid body shape, with a long pointed yellowish bill, long neck, aerodynamic body, long slender wings and pointed tail. The adult is bright white with black wings, a black tail and a dark face mask; at 75–85 cm (30–33 in) long, it is the largest species of booby. The sexes have similar plumage. This species ranges across tropical oceans, except in the eastern Atlantic and eastern Pacific. In the latter, it is replaced by the Nazca booby (Sula granti), which was formerly regarded as a subspecies of masked booby. Nesting takes place in colonies, generally on islands and atolls far from the mainland and close to deep water required for foraging. Territorial when breeding, the masked booby performs agonistic displays to defend its nest. Potential and mated pairs engage in courtship and greeting displays. The female lays two chalky white eggs in a shallow depression on flat ground away from vegetation. The chicks are born featherless, but are soon covered in white down. The second chick born generally does not survive and is killed by its elder sibling. These birds are spectacular plunge divers, plunging into the ocean at high speed in search of prey—mainly flying fish. The species faces few threats; although its population is declining, it is considered to be a least-concern species by the International Union for Conservation of Nature (IUCN).

FamilySulidaeBoobies and Gannets
Puerto Rico occurrenceNative / natural occurrenceAvibase inferred core 380
Primary habitatPelagic waters; offshore nesting islandsPelagic waters; offshore nesting islands
Primary dietFishAquatic predator
Average mass1811.8 gGlobal trait estimate
MovementMigratory; Long-distance dispersal; Sedentary / residentAerial

Sound archive

Hear its voice

Explore real songs and calls. The spectrogram turns each sound into a visual trace of time and frequency.

XC730159Recording 1 of 3alarm call
Spectrogram of Masked Booby: alarm call
SpectrogramSula dactylatra

Play: alarm call by Alán Palacios

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Sound recorded by Alán Palacios · XC730159 · CC BY-NC-SA 4.0. Visualization by Stichting Xeno-canto voor Natuurgeluiden.

Every recording retains the creator, catalogue number, and license published by Xeno-canto. Metadata via GBIF

Island profile

Catalog scopeAvibase inferred core 380

About the Masked Booby

The masked booby (Sula dactylatra), also called the masked gannet or the blue-faced booby, is a large seabird of the booby and gannet family, Sulidae. First described by the French naturalist René-Primevère Lesson in 1831, the masked booby is one of six species of booby in the genus Sula. It has a typical sulid body shape, with a long pointed yellowish bill, long neck, aerodynamic body, long slender wings and pointed tail. The adult is bright white with black wings, a black tail and a dark face mask; at 75–85 cm (30–33 in) long, it is the largest species of booby. The sexes have similar plumage. This species ranges across tropical oceans, except in the eastern Atlantic and eastern Pacific. In the latter, it is replaced by the Nazca booby (Sula granti), which was formerly regarded as a subspecies of masked booby. Nesting takes place in colonies, generally on islands and atolls far from the mainland and close to deep water required for foraging. Territorial when breeding, the masked booby performs agonistic displays to defend its nest. Potential and mated pairs engage in courtship and greeting displays. The female lays two chalky white eggs in a shallow depression on flat ground away from vegetation. The chicks are born featherless, but are soon covered in white down. The second chick born generally does not survive and is killed by its elder sibling. These birds are spectacular plunge divers, plunging into the ocean at high speed in search of prey—mainly flying fish. The species faces few threats; although its population is declining, it is considered to be a least-concern species by the International Union for Conservation of Nature (IUCN).

Conservation

Least Concern

IUCN LC; DNER VU

Global IUCN
LC
Puerto Rico DNER
VU
Federal ESA
No current listing in source crosswalk
Critical habitat
Not identified in source crosswalk

Natural history

How it lives

Habitat
Pelagic waters; offshore nesting islands
Elevation
0–0 m
Nest
Scrape · Ground; Rock
Clutch
1–2 eggs
Social behavior
Colonial

Keep exploring

This bird belongs to 8 paths through the atlas.

Evidence trail

Sources, media & further reading

Research note: Commonwealth VU in cited 2026 compilation