John Shaw / Great frigatebird (Fregata minor) male at nest site, with gular sac inflated to attract females. Genovesa Island, Galapagos, May.

Tui De Roy / Great frigatebird (Fregata minor) male displaying inflated gular sac, Galapagos, Ecuador.

Claudio Contreras / Great Frigatebird (Fregata minor) departing from nest, San Benedicto Island, Revillagigedo Archipelago Biosphere Reserve / Archipielago de Revillagigedo UNESCO Natural World Heritage Site (Socorro Isl...

Tui De Roy / Great frigatebird (Fregata minor) male guarding single chick. Punta Cevallos, Espanola Island, Galapagos, Ecuador, May.

Tui De Roy / Great frigatebird (Fregata minor) male taking flight at dusk. Espanola Island, Galapagos, Ecuador, May.

Cheryl-Samantha Owen / Great frigate birds (Fregata minor) sitting in tree, Aldabra Atoll, Seychelles, Indian Ocean

Pete Oxford / Great frigate bird (Fregata minor) female on nest with chick, Galapagos

Pete Oxford / Great frigatebird (Fregata minor) male displaying, pouch inflated, Galapagos

Pete Oxford / Great frigate bird (Fregeta minor) male with pouch fully inflated. Orgenoves Island, Galapagos

Pete Oxford / Great Frigate bird (Fregeta minor) male courtship display. Galapagos, Tower Orgenoves Island

Pete Oxford / Great frigate bird feeding chick {Fregata minor} Genovesa, Galapagos.

Mary McDonald / Great frigatebird (Fregata minor) male, inflating red gular / throat pouch, Genovesa Island, Darwin Bay, Galapagos Islands. April.