Lonesome or aggressive, mournful or spirited, few sounds in nature thrill and mystify like the nocturnal dirge of this top predator. A listener’s guide to the meaning of wolf howls

By Ray Ford

“It’s a little early for this. My voice isn’t warmed up,” Rick Stronks says apologetically. Then Algonquin Provincial Park’s chief naturalist draws a deep breath, rounds his lips into an oval and tilts his head back.

A long, mournful wail soars over the bog behind the park’s visitor centre, rising over the Jack pines and squawking jays, and dissipating on the wind. When the song fades, Stronks pauses, waiting for the park wolves to respond. But there is only silence. On this sunny, late-March morning, most wolves are pairing up.

To whom am I listening?
Ontario has a “canid stew” of wolf and coyote populations, with species bumping up against one another and in some cases blending together through interbreeding. Three key species inhabit the province:

Eastern coyote (Canis latrans): Smaller and finer featured than wolves, coyotes are grey, reddish grey or tawny in colour. Although originally a prairie species, coyotes thrive in areas of mixed field and forest, and have been expanding their range through southern, eastern and central Ontario.

Eastern wolf (Canis lycaon): More closely related to the red wolf of the U.S. southeast and the coyote than the larger grey wolf, the eastern wolf is listed as “a species of special concern” under federal and provincial endangered species legislation. Ranging as far north as Timmins and south to the area around Algonquin Provincial Park, the eastern wolf is usually tawny grey, often with a reddish tinge.

Grey wolf (Canis lupus): The largest Ontario wolf, it is typically salt-and-pepper grey, sometimes with brown tinges, but can also be almost completely black or creamy white. Grey wolves are found across northern Ontario, in a range that at least partly overlaps that of the eastern wolf.

What will I hear?
Carleton University biology instructor Michael Runtz describes the classic solo call as a “deep-throated, no-oscillation, riseand- fall howl that gets the hair raised on the back of your neck.

Generally, coyotes yip and yap at the start of a howl, and their howls tend to be higher in pitch and oscillate quite a bit.”

When they howl in groups, the two wolf species are harder to tell apart because wolf pups sound like coyotes. When trying to determine which species you hear, keep in mind that coyotes generally inhabit agricultural areas, while wolves stick to more densely forested zones. Chorus howls with lots of yip-yapping in the summer and early fall may be wolves with pups. A similar sound heard during the winter is likely to be that of coyotes.

When should I listen?
Wolf howls are most frequent during the run-up to mating in early spring, when wolves are particularly sociable, and in the late summer and fall, once the pups are out of the den.

During mating and den selection, and while pups are too small to move, wolves howl less, perhaps because doing so would betray their location.

Where should I listen?
Coyote howls can be heard almost anywhere across the southern half of Ontario (even in cities). The animals may be more circumspect in areas they share with wolves. In a confrontation with the larger species, coyotes almost always lose.
For Algonquin Provincial Park’s public wolf howls, naturalists target areas near wolf rendezvous sites – meadows hidden in the forest where packs will leave the pups while older members go hunting. “The main thing I’m listening for is whether pups are present,” Runtz says. Then “it’s easier to find the rest of the pack.”

What will a howl sound like?
Howls carry across long distances because lower pitched, harmonic, sustained sounds carry farther than short, “noisy” sounds such as barks or growls. At its extremes, the wolf howl can range over about three octaves, starting at roughly 150 hertz (in musical terms, roughly the D below middle C) up to above 1,000 hertz. The mean pitch falls between 300 and 670 hertz (from about the D above middle C to the E an octave higher). When American jazz saxophonist Paul Winter used a recorded wolf howl in one of his tunes, he reckoned the animal was howling in D flat.

Researchers who have recorded coyote and wolf calls and analyzed their voice prints have discovered that the size, lung power, larynx and vocal tract of different individuals produce a distinct voice. Pack mates can probably recognize one another, at least over distances of a kilometre or less. And there don’t seem to be regional accents. A study comparing captive Iberian wolves in Spain and Portugal with their North American cousins found few detectable differences between the two groups, suggesting that wolves from different places could communicate.

Why do wolves reply to humans?
“Most animals respond to certain key stimuli,” says Fred Harrington, a Mount St. Vincent University biologist and a veteran howler who has been studying wolf and coyote song since 1971. “A wolf howls back if you get the right set of frequencies and deviations down to fit into the category of ‘this is a wolf.’ Wolves wouldn’t suspect a human is howling, because in wolves’ evolutionary history, the only thing that sounds remotely like them is a loon.”

Things are different in August, when boisterous pups are free of the den and Stronks leads the park’s popular Thursday evening public wolf howls. Then, his call bridges the vast divide between species. More often than not, the wolves reply.

“Sometimes they’ll all howl together in a beautiful, long, sustained howl. Sometimes it’s a single, nonchalant howl,” he says. “I never get tired of it. It’s incredible to hear.” The sound is wild and mysterious. But discerning listeners can sense the feeling – sometimes even the message – behind the song. Despite the many threats to wolves and coyotes, including development, hunting and trapping, their song goes on and grows even stronger. Coyotes yip and warble across the fields and suburbs of southern Ontario. A 2005 Ministry of Natural Resources paper estimates that 8,850 eastern and grey wolves inhabit the northern and central forests, and that even in a province where people outnumber wolves by more than a thousand to one, the generally healthy prey populations make it “likely that wolf numbers in most areas of the province have been either stable or increasing since 1993.”

Because one of the province’s top predators is so elusive by nature, its howl is our most likely point of contact with the wolf. Subtle and near-constant communicators, wolves send signals using posture, gestures, sounds and scents. But when a long-distance call is needed, they throw their heads back and release a drawn-out song that rises and falls, sometimes with the monotony of an air-raid siren, occasionally with the twisting, trailing descents of a John Coltrane sax solo. Their broadcasts reach as far as 10 kilometres in forested areas and up to 16 kilometres on the tundra.

These days, Stronks says, Algonquin is “more or less saturated” with wolf packs, making it a prime location for a course in wolf-howl appreciation. “There are probably about 35 packs in the park,” he adds. “So from your campsite at night, or on a canoe trip, there’s the possibility of hearing wolves.”

More than 140,000 visitors have come to listen since the park’s public wolf howl program began in 1963. Drawing more than 2,000 listeners a night, the howl is “probably the largest naturalist-led interpretation program in North America, if not the world,” Stronks says. “If we don’t have a wolf howl, we still have the wolf talk, and we play tape recordings of wolf howls.” Still, there’s no substitute for the real thing. On evenings when the howl goes ahead, thousands wait patiently in the hopes of hearing the wolves. If only a talk takes place, maybe 400 people show up.

The roots of the public wolf howl reach back to the late 1950s, when biologist Douglas Pimlott was trying to locate wolves concealed in the park’s dense bush. Pimlott played recorded howls on truck-mounted speakers and listened for the response. The broadcasts received an almost instant – and unnerving – reply. The air filled with howls.

At the time, “none of us knew what we were doing in trying to trigger the howl ourselves,” long-time Algonquin wolf researcher John Theberge, who worked as a summer student with Pimlott, recalled in Peter Steinhart’s The Company of Wolves. “We wondered if we were triggering aggression.” The research crew soon found that wolves would respond to a human imitation of a call, making the speakers unnecessary. Sometimes, curious alpha male wolves even visited the researchers.

The crew was triggering one of howling’s central functions: to mark territory and help packs avoid confrontation by spacing them out across the landscape. By howling at the edge of their territories, the members of a pack are posting a kind of verbal no-trespassing sign. Pimlott found that a strange howl inside a pack’s turf will often draw the attention of its leader. When pack members spread out during a hunt, their howls act as audible beacons, helping the animals reunite.

Researchers also speculate that wolves may howl to attract a mate, or simply to express themselves. “The basic information they would be sending is, ‘I’m a wolf,’” says Fred Harrington, a biologist and animal behaviour specialist at Mount St. Vincent University in Halifax. “Perhaps I’m a male or a female. I’m this individual wolf. I’m feeling this right now.”

The howl serves a social purpose, too. A group howl resembles a campfire singalong, with pack members mingling voices, wagging tails and wriggling bodies, often before or after hunting. It is a bonding exercise, a chance to cut loose when the gang is together, but it also has the practical benefit of letting pack members hear each other. “If you’re going to use howling as a form of long-distance communication, you have to know what each member of the pack sounds like,” Stronks says.

For human eavesdroppers, the easiest distinction is between solo wolf performances and group efforts. Solo howls typically last no longer than 14 seconds and can be “flat” (with little rise or fall), arcing or “breaking” (with discontinuous, trailing “blue” notes at the fall).

Choruses start with a single call but soon become successions of intermingling howls that last as long as two minutes. Group howls are more variable and more animated, and range more widely along the frequency spectrum than solos, especially if pups join the glee club. Pups are so “juiced to howl,” Harrington says, that even a siren or a loon call will set them off. Harrington adds that the general cacophony of a group howl often leads listeners to overestimate the size of a pack – and that may be precisely the howlers’ aim. If two or three wolves can sound like a legion of aggressive competitors, they can intimidate neighbouring packs, gain a little elbow room for hunting and garner an evolutionary advantage over less raucous vocalists.