A Crested Auklet colony during the summer is . It鈥檚 loud, with hundreds or thousands of birds clattering and squawking. Each bird is a visual spectacle: Decked out in dusky gray, they look like five-year-olds who broke into Mom鈥檚 makeup, with orange Joker smiles, extravagant white eye plumes, and gravity-defying feather crests. And then there鈥檚 the smell鈥攁 bright tangerine scent so fragrant that researchers can sniff out the birds鈥 colonies, which are found on islands off Alaska鈥檚 coast, from more than a hundred yards away.
鈥淭hey鈥檙e pretty much the craziest little birds that you could ever imagine,鈥 says , a seabird biologist at the University of New Brunswick in Canada. Crested Auklets are so unusual that three of their traits haven鈥檛 been found in any other birds to date. And all of these unique physical traits appear to play some role in the auklets鈥 social and sex lives鈥攚hich are pretty freaky, even for birds.
Take that crest鈥攖he 鈥渨eird little forward-facing ponytail,鈥 as Major puts it鈥攐f about a dozen feathers that curl over an auklet鈥檚 beak between its beady eyes. The crest鈥檚 length helps birds assess whether they鈥檙e interested in a possible mate, conducted by , a seabird ecologist at Memorial University in Canada who has spent 25 years studying Crested Auklets. In an exception to the bird stereotype of flashy males and drab females, both male and female auklets display these crests. Jones says his team鈥檚 paper, published in 1993, was the first experimental confirmation of mutual sexual selection, a phenomenon predicted by Charles Darwin. 鈥淭here鈥檚 a kind of prejudice in the field that it鈥檚 only females that are choosy,鈥 he says. 鈥淲e sort of blew that out of the water.鈥
Photo: Ian L. Jones
Major may be on the path to confirming a second unique feature in Crested Auklets: a social odor, a strong citrusy scent that may just be the first avian example of an odor that affects social interactions. Scented feathers on their own aren鈥檛 that unusual鈥攏ature has produced . For other birds, scents are used to navigate or deter predators. But Crested Auklet perfume is different: based on their energetic mating rituals (more on that later), Jones suspects the smell may encourage females to approach displaying males. He鈥檚 tried to confirm it , but it鈥檚 logistically tricky because the scent fades quickly once feathers are removed from a bird. Other scientists argue the tangerine perfume gives Crested Auklets a bit of protection against parasites.
Perhaps the oddest of the Crested Auklet's three special traits is their fluorescent bills, which were recently by some field researchers. Part of their work included collecting dead birds to create museum study skins. When a bad storm left them cooped up at camp, the bored scientists shined around a diving flashlight that emits blue light, just to see what happened. 鈥淲hen the light passed over the preserved auklets that we had, the bills just lit up. It was really intense,鈥 says , a PhD student at Northern Illinois University. It turns out that the Crested Auklet鈥檚 bill plates鈥攖emporary structures that surround their beak during mating season鈥攁re the first-known bird part (besides feathers) that fluoresce. In fluorescing, the plates don't just reflect light the way colored surfaces do, but .
The researchers don鈥檛 yet know why Crested Auklets have fluorescent bill plates. But Wails and her colleagues think the brilliant color鈥攍ike the birds鈥 other quirks鈥攃ould have something to do with a strange Auklet mating ritual in which beaks play a prominent role.
It Starts With a 'Ruff Sniff'
At most seabird colonies, there鈥檚 a rush of courting and mating at the beginning of the season. But Crested Auklets are kinkier than most seabirds: when two birds court, they do so surrounded and egged on by a whole bunch of other birds in a behavior known as a scrum.
A scrum forms around a male showing off his wares, including his impressive feather crest. He puffs up his body, stretches his neck, and honks, while his black pupils shrink to display a strikingly shiny white iris. If a female (or occasionally two) decides she鈥檚 interested, she will cautiously approach, and her own feather crest will help the male decide if he鈥檚 interested in her advances. If so, she buries her beak in the male鈥檚 neck feathers鈥攚here that fresh tangerine scent is strongest鈥攊n a move called a 鈥.鈥 The birds also cackle and touch those brilliant orange beaks together. If they hit it off, they鈥檒l twist their necks around each other and rub.
The scene is loud, bright, and smelly enough to attract attention from lower-ranking birds, including juveniles and both male and female adults, who gather around the central mating pair in a scrum. These scrumming birds crowd around, jostling each other to try to get closer to the two courting birds. In particular, they try to rub necks with the mating bird of the opposite sex. 鈥淚t鈥檚 up to 15 or 20 birds in a heap, just partying, going crazy,鈥 Jones says. The birds are so invested in touching the central pair that they often end up standing on each other.
When the party鈥檚 over, the pair will take a few days to cool off. If they鈥檙e still into each other after that brief respite, they鈥檒l meet up out on the ocean to mate. They again gather a crowd with similar scrumming behavior, although it's been studied less at sea.
The Crested Auklets' closest relatives, while not quite at the same level of weirdness, are also impressive. Three other species of auklet鈥擫east, Parakeet, and Whiskered Auklets鈥攁re highly ornamented. Meanwhile, the Cassin鈥檚 Auklet, a nocturnal species, makes complex screeching vocalizations. 鈥淚t鈥檚 really just kind of sexual selection running rampant in this group, and particularly in Crested Auklets,鈥 Jones says.
Each August or September, the birds become a bit more ordinary, losing their ornaments and flying off, the birds close enough to whack each other with their wings mid-air, to spend the fall and winter on the ocean. But come late spring, they鈥檒l be back on land in their finery, ready for another round of ruff-sniffing and scrumming鈥攁nd perhaps revealing still more secrets to watching scientists.