For the Blue-footed Boobies the deep blue is the color of the opportunities
Blue-footed boobies (Sula nebouxii) are socially monogamous sea birds with a mixed-reproductive strategy where extra pair copulations may be frequent. Males and females have colorful feet that are displayed ostentatiously during courtship, both before and after pairing.
During courtship, males and females exhibit their feet to their partner. Males land in the territory with spread feed held flung up and in front of their underparts producing a conspicuous contrast between the color of the foot-web and the white underparts. It is something like a salute-landing.
The sexual advertising display is frequently preceded or followed by a parading consisting of an exaggerated foot-rising, flaunting the webs upwards and outwards. As part of the courtship ritual, it is customary for the male to offer his love interest a twig. Should the female Booby accept the twig, the courtship is finished and the two will mate.
A field investigation conducted involving the modification of the feet color of males in established pairs, indicated that male foot color is important for female motivation to court and to copulate within the pair. As the color of the foot is related to the nutritional state of the individual, females reduced their courtship motivation when their male partner had duller feet. Hence, female motivation to court apparently depends on the condition of the male, expressed by foot color.
Moreover, in another study, when the color of the females feet was modified, the females with duller feet receive less intra- and extra pair courtship, suggesting that foot color influences female attractiveness and opportunities for extra pair interactions.
In the photos you can see a dejected looking male doing his best to win the favor of the distracted female. However, after some time, this male Booby’s twig was never accepted, and eventually a second male sensed opportunity and came along. With the coming of the new male, this male Booby waddled off, leaving behind his twig.
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Photo credit: ©Todd Bretl [Top] - [Bottom]
Locality: North Seymur Island, Galapagos Islands, Ecuador