606. On She-Male Western Marsh Harriers

A female Western Marsh Harrier

By James Gorman, The New York Times, November 14, 2011

The Western marsh harrier is a typical hawk. It has a sharp beak and talons, which it uses to kill other creatures for food and to defend its territory. It’s the kind of bird that exemplifies military virtues, and it’s no wonder that it has a fighter jet, the British-made Harrier, named after it. Recent science, however, has discovered another side to the harrier that may not fit as well with the rather macho military image. Some harriers have evolved an alternative lifestyle — cross-dressing.

Hawks don’t wear clothes, of course, or makeup or stiletto heels, so they can’t dress at all, strictly speaking. But they do depend on appearance, in their case plumage, to advertise their sex. The males have light gray wings and the females dark wings. Usually. In one population in western France, however, about 40 percent of the males have permanent female plumage, according to a report in Biology Letters, a publication of the Royal Society (that’s British, not French royalty).

Audrey Sternalski, and her colleagues who contributed to the report, uncovered the extent of this deception and also studied the hawk she-males. I didn’t just grab that word from the Internet, by the way. It came from a paper in Nature on garter snakes published quite a while ago. The authors referred to snakes, in which female mimicry is common, as she-males and he-males, so I figure those are scientific terms.

Many different creatures — particularly fish and reptiles and insects — engage in female mimicry. Garter snake males may emit chemicals called pheromones to suggest that they are female, but they do this for only a couple of days after they emerge from winter dens. Apparently, their goal is to get warm. Garter snakes form mating balls of 100 males or more around real females. She-males attract enough males to give them a snake-hug, and once they’ve warmed up, turn off the pheromones.

Among birds, only two species are known in which adult males may have permanent female plumage. The first one to be studied is the ruff, a shorebird that gathers in large groups during mating season. The ruff she-males sneak around, pretending to be female, avoiding competition with he-males and stealing kisses, or as scientists call them, extra-pair copulations. Humans do the same thing, at least in movies (Tony Curtis, “Some Like It Hot”) and short-lived television sitcoms featuring future megastars (Tom Hanks, “Bosom Buddies”).

Dr. Sternalski, of the Institute for the Study of Hunting Resources in Ciudad Real, Spain, and her Spanish and French colleagues used decoys to see if the she-male hawks were attacked by other males as often as the he-males were. As they suspected, the she-males flew under the he-male radar. They were not attacked or challenged by the other males. They also behaved like real females, directing their aggression toward females, not males. One surprise was that when it came to outside threats they were more actively aggressive than the he-males. When predators (or predator decoys) threaten the winter roost, Dr. Sternalski said, the “typical males manipulate the others to defend the roost.” The he-males recruit the she-males to attack the apparent intruder while they do the hawk equivalent of sitting on the stoop shouting encouragement: “Look out for the fox!”

For all this work, there has to be some payoff for the she-males other than simply avoiding challenges from other males. The best guess so far is that the she-males are going for those prized extra-pair copulations, and Dr. Sternalski is testing that idea now.

Research into bird behavior does not usually have an immediate effect on society. But hawks have a long history as military symbols, and I wonder how this news will be greeted by the folks who wear eagles on their epaulets, and those who give military aircraft names like Nighthawk, Jayhawk, Hawk and Black Hawk.

The armed forces in the United States have come around to the idea that men and women, heterosexuals and homosexuals, can be soldiers, but they are still sticklers about plumage. Hot pink lipstick is not included in battle gear. Could the discovery that some of those symbols of bravery and battle toughness are the bird equivalent of transvestites mean the uniform code will loosen up?

The comedian Eddie Izzard, who describes himself as an action transvestite — “running, jumping, climbing trees, putting on makeup while you’re up there” — once described his crushed childhood ambition to join the army. He suggested that the military could be more flexible about fashion, and capitalize on the element of surprise in its attacks. “What,” he asked, “could be more surprising than the First Battalion Transvestite Brigade?”

Just a joke, of course, a little poke in the ribs to conventional masculinity, a suggestion that hot pink lipstick and fabulous lashes don’t mean you can’t shoot or punch, or attack predators when they come near the nest. There will never be such a brigade, but if there were, I have an insignia in mind: a she-male marsh harrier on a field of earth tones with eyeliner in one talon and lipstick in the other.