Genovesa Island

This is an island that amazes everyone. Here we enjoy seeing many species of seabirds flying, courting and nesting. Every where you look you find a bird doing something and today was no exception. Birds everywhere were extremely active and seemed thrilled, not only with the interactions going on between them, but also with our presence. The young red-footed boobies watched us with much interest as we walked beneath the trees where they perched. And of course, the best show on the island was seeing the great frigate birds displaying.

As the weeks go by we find fewer male frigates courting. Today we found only a handful of male frigate birds with their gular sacs still inflated trying to attract the females. Now, don't think that if a bird inflates his sac today, he will attract a female right away. No way. The males have to compete with each other before they are rewarded by the presence of a female. Female frigates seem to take their time choosing the desirable male to mate with. When it comes to selecting a mate, females are the finicky sex. This is simply relates to the fact that the female invests a lot in the gamete and in the resulting offspring.

During frigate bird courtship, the male inflates his gular sac, spreads his wings and calls, and waits for a female to select him. Only after he has been chosen does he deflate the sac. The poor fellow has to look his best and keep up the display even if he is hungry and wants to go out fishing; it's a tough life for these guys! One assumes that the female frigates select a mate based on not only gular pouch size, shape, and brightness, or the sounds that the male is emitting, but also the attractiveness of the nest site. As you can see, there are many animal behaviors that are not very different from ours. This photo shows us Mr. and Mrs. Great Frigatebird (Fregata minor) after she has decided that this male will be her mate for this season. Lucky male!