Sula Sula Research Articles

The Breeding Ecology of the Red-Footed Booby in the Galapagos

The Breeding Ecology of the Red-Footed Booby in the Galapagos

Egg-Eating by Galápagos Mockingbirds

The Galapagos mockingbirds (Mimidae) belong to the endemic genus Nesomimus, and it is generally accepted that there are four distinct species: N. trifasciatus (on Champion and Gardner-by-Floreana), N. melanotis (on San Crist6bal [= Chatham]), N. macdonaldi (on Hood [= Espafiola]), and N. parvulus -seven subspecies on different islands not inhabited by any of the other species (Swarth, Occas. Papers Calif. Acad. Sci. 18:1, 1931). It is therefore of some interest that Hatch (Condor 67:354, 1965) reports that only one species, N. macdonaldi, feeds on seabird eggs. N. trifasciatus and N. parvulus he found did not, and he does not mention N. melanotis, and says that is an interesting example of a behavior pattern differing strikingly between closely related species. On Hood Island N. macdonaldi, which has by far the largest bill of any of the species, is frequently seen attacking the unincubated eggs of the Galapagos Albatross (Diomedea irrorata), Blue-footed Booby (Sula nebouxii), Masked Booby (S. dactylatra), and Swallow-tailed Gull (Creagrus furcatus). L6veque (Alauda 32:5, 1964) reports these mockingbirds as eating the eggs of the American Oystercatcher (Haematopus palliatus), and on several instances I have seen them take the eggs of the Galapagos Dove (Zenaida galapagoensis). However, in the normal course of events it is unlikely that many eggs of any of these species are available to the mockingbirds except when extreme adverse conditions, such as food shortage or human interference, drive the birds from the nests. Also it must be only infrequently that the birds manage to crack an intact egg of the larger seabirds, although they would soon devour a hatching or cracked egg. Alan Root tells me that in 1966 the mockingbirds were pecking at bleeding wounds on the feet of the albatrosses. The mockingbird on Tower Island (N. parvulus bauri) was noted by Hatch (op. cit.) to be indifferent to the eggs of the abundant seabirds and even to freshly broken eggs. However, during field work on Tower Island in 1966-67, it was seen that this species would eagerly eat eggs of the Red-footed Booby (S. sula) and frigatebirds (Fregata minor) broken by other frigates or Lava Gulls (Larus fuliginosus) and would even peck furiously at unattended frigratebird eggs and try to eject them from the nests when the adults were scared away by human intruders in the colony (fig. 1). There is on Tower Island an extremely large colony of the Wedge-rumped Storm-Petrel (Oceanodroma tethys) which lays eggs in the large but well-protected open spaces under the lava flows. Large numbers of broken eggs are found near the nest sites, and Nelson (Ibis 108:430, 1966) thought that these had not been eaten by mockingbirds (he infers by the use of the abbreviation Nesomimus spp. that there is more than one species present, but there is no evidence for this) but were more likely a result of interspecific competition for nest sites. Close inspection of the colony, however, has now shown that the majority of these eggs have been ejected by competition (but intraspecific) and then eaten by mockingbirds. Great care had to be taken while examining petrel nests as the ?~

A Specimen of the Red-Footed Booby from Florida

A Specimen of the Red-Footed Booby from Florida

Temperature Regulation in the Red-Tailed Tropic Bird and the Red-Footed Booby

This paper represents part of a study on the thermoregulatory responses of nesting sea birds to natural environmental conditions. The investigations were conducted on Midway Island. Our previous publications (Howell and Bartholomew, 1961a, 1961b) have dealt with Laysan and Black-footed albatrosses (Diomedea immutabilis and D. nigripes), Bonin Island Petrels (Pterodroma hypoleuca), and Wedge-tailed and Christmas Island shearwaters (Pufinus pacificus and P. nativitatis). Bailey (1956) gives a useful account of the natural history of these and other species found on Midway. In the course of visits to Midway Island in June and July, 1959 and 1960, we were able to obtain data on thermoregulation in the Red-tailed Tropic Bird (Phaethon rubricauda) and the Red-footed Booby (Sula sula). Aside from the work of Probine and Wodzicki (1955) on the Gannet (Sula bassana) and that of Bartholomew, Dawson, and O'Neill (1953) and Bartholomew and Dawson (1954) on pelicans (Pelecanus), we know of no quantitative studies on thermoregulation in pelecaniform birds.

Nesting Activities of the Red-Footed Booby in British Honduras

FROM 14 February to 9 May 1958 I conducted an intensive investigation of the breeding activities of the Red-footed Booby (Sula sula sula Linnaeus) on Half Moon Cay, 80 km east of Belize, British Honduras. The detailed results of the study appear in my thesis for the degree of Master of Science (Verner, thesis submitted 1959). Half Moon Cay (Figure 1) is a tiny coral island, 1.16 km in length, supporting mainly coconut palms (Cocos nucifera). The floor of the narrow eastern half of the cay has been cleared, and the palms there are planted in rows. On the western portion, exclusive of the booby colony, the palms are distributed naturally, the floor beneath being covered with lush, mat-forming herbs. Within the booby colony very few palms are present; instead, eight species of broadleaf trees form a nearly continuous overhead canopy from about six to 15 meters above the ground. The number of booby nests in each species of tree fairly well indicated the relative abundance of each species (Table 1). The floor of the colony is composed of coral stones, which permit potential humus to percolate away with the rains. As a result, there is little in the way of an herbaceous understory. The only undomesticated mammal on the cay is Rattus rattus. Ninetyeight species of birds were recorded during the course of the study. At least 77 of these were migratory forms, and, of these, only 17 were recorded regularly enough to indicate that they winter on or near the island. Two species, the Red-footed Booby and the Magnificent Frigate-bird (Fregata magnificens), were nesting at the time of the study; and probably both the White-crowned Pigeon (Columba leucocephala) and the Groove-billed Ani (Crotophaga sulcirostris) nested there later in the year. A number of small lizards and two larger ones, the False Iguana (Ctenosaura similis) and the Iguana (Iguarna iguana), were abundant. Nothing was observed to substantiate the many reports that these larger lizards harm nests, eggs, and young of the Red-footed Booby. The climate at Half Moon Cay is generally mild, although the high humidity makes even slight temperature differences more noticeable. Temperatures were recorded three times daily-morning, noon, and night-between 20 March and 7 May and the range was from 23?C (730F) to 320C (900F). With the exception of the early morning average of 26?C (790F) in March, all three daily averages for March,

Occurrence of the Red‐footed Booby at Ascension Island

IbisVolume 89, Issue 1 p. 122-123 Occurrence of the Red-footed Booby at Ascension Island First published: January 1947 https://doi.org/10.1111/j.1474-919X.1947.tb04927.xCitations: 2AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article.Citing Literature Volume89, Issue1January 1947Pages 122-123 RelatedInformation

Name of the Red-Footed Booby

Name of the Red-Footed Booby