Wooing and home building proceeded in the silence of a primitive charade. The adult brown pelican neither sings nor calls; therefore its language of gesture and movement is highly developed.
Evolved over eons, the displays are signals to male and female alike that an individual is aggressive, submissive, or sexually aroused. On early trips to Tarpon Key I found its central lagoon at low tide a treacherous mud flat, sucking me in sometimes to my armpits. I soon learned to coordinate visits with high tide, when I could easily row my 13-foot Boston Whaler around the lagoon.
From October to February, Tarpon Key is empty of pelicans, although many of them re-main in the Tampa Bay vicinity, fishing, posing for tourists, and panhandling in small flocks. Then suddenly, in late February, hundreds of adult birds descend on the island, ushering in the breeding season.
At the start of my pelican watching, I could not distinguish males from females and did not understand the birds’ strange posturings and mock attacks. So, to observe their daily habits, I built a 12-foot tower about 25 yards from a cluster of mangroves where a large group of pelicans had built nests. The birds did not seem disturbed by my presence.
Spring courtship, I found, is a time of high drama. The male pelican, distinguished from the female not by plumage but by a slightly heavier build and a noticeably longer bill, picks the nest site in the mangrove branches.
Figure-eight Wobble Wins a Mate
From my tower, in the second spring of my study, I watched a pair of pelicans I called Cas and Bill set up family life. His territorial claim staked out, Bill sought to attract a fe¬male with an odd soliciting display: a single or repeated sideways head movement in a figure-eight pattern. It seemed almost as though he were sharpening his bill on a razor strop. Before long Cas succumbed to these wiles and alighted near the site.
Now the courtship began in earnest. Cas had to be pushy enough to intrude into the territory that Bill defended, yet properly submissive, so that he would allow her to approach. Bill had to defend his site against intruding males without being so aggressive that he drove away his chosen mate as well.
Before long, wooed and won, Cas was standing on the nest site beside her mate, and Bill now began a two-week-long series of trips to bring sticks and grasses to Cas, who stayed home to build the nest.