Nesting takes place in colonies, generally on islands and atolls far from the mainland and close to deep water required for foraging.

The French naturalist René Lesson was a member of the crew on the La Coquille, captained by Louis Isidore Duperrey, on its voyage around the world undertaken between August 1822 and March 1825.

In his 1829 account of the visit to Ascension Island in the South Atlantic Ocean, Lesson mentioned encountering masked boobies, and in a footnote proposed the binomial name Sula dactylatra.

[5] The Swedish zoologist Carl Jakob Sundevall described the species as Dysporus cyanops in 1837[6] from a subadult collected in the Atlantic Ocean on 6 September 1827.

[12] Sundevall's binomial name was followed as Lesson's 1829 record did not sufficiently describe the species; however, in 1911, the Australian amateur ornithologist Gregory Mathews pointed out that although Lesson's 1829 account did not describe the bird, his 1831 account did, and thus predated Sundevall by six years, and hence Sula dactylactra had priority.

Birds in the Atlantic are the smallest, with the size increasing westwards though the Pacific to the Indian Ocean, where the largest individuals are found.

[30] The sexes have similar plumage with no seasonal variation, but females are on average slightly heavier and larger than males.

[19] For the subspecies tasmani and the nominate dactylatra, during the breeding season, the leg colour of male birds contains more yellow-red than those of the females.

[19] Abbott's booby (Papasula abbotti) has a more wholly black upperwing, and a longer neck and tail and larger head, while the Cape gannet (Morus capensis) and the Australasian gannet (Morus serrator) have a buff-yellow crown, shorter tail, white humerals and a grey rather than yellowish bill.

[39] In the Atlantic, Caribbean birds occasionally wander north to warm southern Gulf Stream waters off the eastern seaboard of the United States, with single records from Island Beach in New Jersey and New York.

[43] During the monsoon season (midyear), the masked booby is an occasional vagrant along the western coast of India, with records from Kerala, Karnataka,[44] and Maharashtra states.

[30] On these landforms, masked boobies select sites of generally flat, bare or exposed open ground that lie above the high-tide level with access to the ocean.

[30] The largest masked booby colony is on Clipperton Island in the eastern Pacific Ocean,[19] a desert atoll southwest of Mexico.

Hunting by humans is thought to have played a role; although rats were introduced to the island in 1918, there has been no evidence they are able to kill chicks or eggs—possibly due to the size of the adult boobies.

[50] In 2006, two pairs nested in a brown booby colony on Morros del Potosí (White Friars Rocks) near Zihuatanejo in southern Mexico.

Highly territorial when nesting, single males and mated pairs engage in agonistic displays to mark their ground against neighbours and interlopers.

In the pelican posture, a bird tucks the tip of its bill into its chest, possibly positioned to avoid injury to others.

The male may also parade in front of the female, walking with an exaggerated high-stepping gait and intermittently tucking his head in his breast, after collecting nesting material and before the pair begins laying.

The male presents small sticks and debris as nesting material in a gesture of symbolic nest-building, which leads to copulation.

On the Cocos (Keeling) Islands, egg-laying takes place from January to July, peaking in June, with juvenile birds from April to December.

[50] In the northern hemisphere, egg-laying on Kure Atoll can be any time from January to early July, peaking in February and March.

[63] When first hatched, the chicks are about 10 cm (3.9 in) long and weigh around 40–60 g (1.4–2.1 oz), with a sparse covering of white down over their grey to pinkish-grey skin.

[19] Species eaten include various species of flying fish such as blue flyingfish (Exocoetus volitans), mirrorwing flyingfish (Hirundichthys speculiger), sailfin flyingfish (Parexocoetus brachypterus), glider flyingfish (Cheilopogon atrisignis) and Atlantic flyingfish (Cheilopogon melanurus), other fish such as yellowtail amberjack (Seriola lalandi), skipjack tuna (Katsuwonus pelamis), mackerel scad (Decapterus macarellus), pompano dolphinfish (Coryphaena equiselis), mahi-mahi (Coryphaena hippurus), brown chub (Kyphosus bigibbus), redbarred hawkfish (Cirrhitops fasciatus), snake mackerel (Gempylus serpens), frigate tuna (Auxis thazard), Pacific saury (Cololabis saira), ribbon halfbeak (Euleptorhamphus viridis), flat needlefish (Ablennes hians) and mullet of the genus Mugil, and the purpleback flying squid (Sthenoteuthis oualaniensis).

[69] Silver gulls (Chroicocephalus novaehollandiae) and buff-banded rails (Gallirallus philippensis) prey on eggs and young.

[53][71] The tick species Ornithodoros (Alectorobius) muesebecki was described parasitising nesting blue-faced boobies off the Arabian coast.

[74] Rats prey on eggs and young of many seabirds, though the size of masked boobies probably prevents direct predation.

[47] The Taíno ate masked and red-footed boobies that nested on Grand Turk Island around 1000 years ago.

[75] Masked booby young and eggs were eaten by the crew of HMS Supply on Lord Howe Island.

[25] The International Union for Conservation of Nature (IUCN) lists the masked booby as a species of least concern, though the population worldwide is decreasing.

[1] At Clipperton Island, the colony was benefitted by the presence of yellowfin tuna (Thunnus albacares), which drove their prey item—flying fish—to the surface, facilitating predation by boobies.