Brown Booby Life History


Habitat OceansNests on islands, covering a wide range of vegetation types, geologic features, and weather patterns. Found at sea in nonbreeding season.Back to top


Food FishSquid and fish, especially flying fish.Back to top


Nest Placement

Nest Ground

Nest Description

Mound of branches, bones, grass, human-generated trash, or other items. Placed on flat ground, usually in full sunshine. Nests in colonies.

Nesting Facts
Clutch Size:1-3 eggs
Egg Description:Pale bluish or greenish, with white outer layer.
Condition at Hatching:Blind and helpless.
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Behavior Aerial Dive (water)Plunge-dives from various heights up to 15 m (50 feet). Folds wings next to body at beginning of dive, then thrusts wings straight out over back, touching in the middle, just before breaking the surface. Dive may reach just below surface, or to as much as 2 m (6 feet) deep. Commonly feeds in areas where large predatory fish such as tuna drive smaller fish to the surface. Also follows fishing vessels.Back to top


Conservation Low ConcernBrown Booby populations are declining. The Waterbird Conservation for the Americas estimates a population of 280,000-300,000 breeders, rates the species a 14 out of 20 on the Continental Concern score, and considers it a Species of High Concern. Brown Booby are on the 2014 State of the Birds Watch List, which lists bird species that are at risk of becoming threatened or endangered without conservation action. Brown Booby no longer breeds on many tropical islands where predators have been introduced. Human population growth and development of islands have caused severe population declines over the past century in the Caribbean.Back to top


Kushlan, J. A., M. J. Steinkamp, K. C. Parsons, J. Capp, M. A. Cruz, M. Coulter, I. Davidson, L. Dickson, N. Edelson, R. Elliott, R. M. Erwin, S. Hatch, S. Kress, R. Milko, S. Miller, K. Mills, R. Paul, R. Phillips, J. E. Saliva, W. Sydeman, J. Trapp, J. Wheeler and K. Wohl (2002). Waterbird conservation for the Americas: The North American waterbird conservation plan, version 1. Washington, DC, USA. 

Lutmerding, J. A. and A. S. Love. Longevity records of North American birds. Version 2015.2. Patuxent Wildlife Research Center, Bird Banding Laboratory 2015.

North American Bird Conservation Initiative. 2014. The State of the Birds 2014 Report. US Department of Interior, Washington, DC, USA.

Schreiber, Elizabeth A. and R. L. Norton. 2002. Brown Booby (Sula leucogaster), version 2.0. In The Birds of North America (P. G. Rodewald, editor). Cornell Lab of Ornithology, Ithaca, New York, USA.

Sibley, D. A. (2014). The Sibley guide to birds, second edition. Alfred A. Knopf, New York, USA.

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