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Tucson Audubon Society Reprinted from the February, 2001 Vermilion Flycatcher, newsletter of the Tucson Audubon Society. Avian
Romantic Rituals Circa Valentine’s Day I began by looking in the 3rd edition of Davis & Russell’s Finding Birds in Southeast Arizona, where I found that only the Harris’ Hawk breeds here all year round, and that only the Mourning Dove, the Barn Owl, the Curved-bill Thrasher, the Red Crossbill, and the Lesser Goldfinch breed before February 14th. In addition to the Anna’s Hummingbird the following birds begin breeding in mid-February: Pied-billed Grebe, Common Moorhen, Red-tailed Hawk, Great Horned Owl, Golden Eagle, Mourning and Inca Doves, Say’s Phoebe, Phainopepla, Starling, and Abert’s Towhee. Two birds, the Anna’s Hummingbird and the Great Horned Owl, seemed to me to be in particular contrast with regard to their courtship and breeding behaviors as described in a series of monographs published by The Academy of Natural Sciences of Philadelphia. In that series one of our renowned members, Stephen M. Russell, notes in his monograph about the Anna’s Hummingbird that there is no pair formation. He states that “males and presumably females may copulate with more than one mate.” I began to wonder about Anna. Was she remote and mysterious? Were she and her husband promiscuous? Was she solely responsible for child-rearing? Here is the scoop about Anna. Prince François Messena was a nobleman who was intensely interested in natural history. It was he who introduced John James Audubon to French society in the early 1800s. That the Prince’s wife, Anna de Belle Messena was as beautiful a woman as her name suggests, was commented upon by Audubon in his writings. So it was fitting that Rene P. Lesson, a French naturalist, named one of the hummingbirds in the Prince’s collection after Anna. [Note that it was Lesson who named the Rivoli’s Hummingbird in honor of the Duke of Rivoli; but that wasn’t impressive enough, so in the 1980s the name was changed to Magnificent Hummingbird.] For the Anna’s Hummingbird courtship begins when a female enters the core of the male’s breeding territory probably for the purpose of building a nest or feeding. She may be chased immediately or she may perch, which will elicit a dive display, where the male dives steeply and rapidly towards the female, making a loud explosive popping sound at the end of his dive. Then the Anna’s male chases the female. She leads him to her nesting area, and ultimately she perches. Russell notes that the male may sing what has been called a “high intensity song” (buzz phrases which continue for several minutes without a break) and perform a shuttle-flight display, where he flies back in forth four to six times in front of a perched female producing a whistling sound with his bill slightly open. The female follows the male’s movements with her bill, and Johnsgard, citing Schuchmann, noted that when she opens her bill slightly, the male alights beside her and begins copulation. But then again, the female may keep the male at a distance by tracking his flight and holding her body erect and partially spreading her tail. Russell states that copulation, which lasts 3 to 5 seconds, is the only time that Anna’s male and female are together. The nest is built by the female, who may continue this work even after the eggs are laid. And it is the female who is the sole parent to incubate and to feed the young. What about other hummingbirds? Writing about hummingbirds in general, Kaufman states: “The female has a simple role in nesting: she does everything. After mating, the male and female hummingbird go their separate ways. Considering the amount of feeding that a hummingbird must do just to keep itself alive, it seems remarkable that one adult is able to raise young all by itself.” Kaufman notes that the female Black-chinned Hummingbird may raise three broods; she may begin building a second nest while still feeding fledglings from the first. Looking at other monographs, I found that Broad-tailed Hummingbirds and Costa’s Hummingbirds (both sexes) are described as “promiscuous.” Perhaps a more stolid bird will provide a contrast to the high energy hummers. The Great Horned Owl breeds in southeastern Arizona between mid-February and mid-June. It is not known whether the male initiates the territory that includes the nest site, but it is presumed by Houston, Smith, and Rohner that he does so. The male owl approaches the female with much bowing and hooting. He cocks his tail, swells his white bib of neck feathers, and “with much bobbing and jerking utters a series of sonorous calls that elicit calling responses by female.” Then there is a cautious approach to the female, “continuing with much tail-bobbing and posturing.” The two birds engage in “bouts of calling (duetting) and bowing with wings drooped or cocked at angles to the body.” According to Houston et al., “calling and posturing is alternated with sometimes extensive periods of mutual bill-rubbing or preening of feathers of head, neck, or chest as an aid to pair-bonding. The authors cite Voos (1988), who found that “courting pairs also engage in high-pitched giggling, screaming, and bill-snapping.” During courtship female Great Horned Owls responded only to every second male call, which was given on a average of 0.8 calls/minute, and the females waited 2-4 seconds to respond. However, during copulation, the male calls increased to 2.7 calls/minute and the female to 2.3 calls/minute. The male “stretched his wings and flapped about 4 times/second to keep his balance. ... As he treaded, his beak feathers nuzzled feathers of female’s nape.” (I’d say this is very romantic under definitions 4 and 5 above.) Houston et al. noted that copulation lasts 4-7 seconds. Such sexual activity was observed to have been repeated 12 times one evening by the same pair. Usually copulation concludes courtship. But while Great Horned Owls, like other owls and falcons, do not build their own nests, a male and female do roost together (unlike hummingbirds) at different locations before a definitive site is chosen and egg-laying begins. This seems quite romantic, and so does the fact that, after egg-laying, the male owls roost close to the nest until the young fledge. Only the female incubates the eggs, but the male delivers prey to her at intervals throughout the night. (That’s what I would expect from a romantic guy!) Pairs may remain in the same territory throughout the year. Great Horned Owls are monogamous; no polygamy has been detected even at peak of prey cycles. (Most would agree that this quality of fidelity is a good example of idealized behavior and therefore an indication of a romantic relationship as set forth under definitions 4 and 5 above.) All in all, I conclude that hummingbirds must perceive of their relationship as fleeting and perhaps romantic under definition 2) above; i.e., imaginary. However, I find Great Horned Owls to be very romantic under definition 4) above: perhaps remote, but certainly idealized and heroic, considering the fidelity shown despite the fact that copulation usually takes place only one night a year. Given that infrequency, the ritualized behavior of these nocturnal birds lends new meaning to the phrase: “Tonight’s the night!” Bibliography Johnsgard, Paul A., The Hummingbirds of North America, 2nd edition, Smithsonian Institution Press, Washington (1997) Kaufman, Kenn, Lives of North American Birds, Houghton Mifflin, New York (1996) Bird questions? Check Birding | General questions? Contact: Tucson Audubon Society | Webmaster: Email This page was updated on 02/21/06 |