Sharon Levy ORDON HABER was tracking a wolf pack he had known for over 40 years when hisplane crashed on a remote stretch of theToklat river in Denali national park, Alaska,last October. The fatal accident silenced oneof the most outspoken and controversialadvocates for wolf protection. Haber, anindependent biologist, had spent a lifetimestudying the behaviour and ecology of wolvesand his passion for the animals was obvious."I am still in awe of what I see out there," hewrote on his website. "Wolves enliven thenorthern mountains, forests, and tundra likeno other creature, helping to enrich our stayon the planet simply by their presence as otherhighly advanced societies in our midst."His opposition to hunting was equallyintense. He excoriated the "heavygovernment-sanctioned killing" and"Mengele-like experiments" with wolf sterilisation in Alaska, which, as he saw itthreaten to transform the very nature of thewolf. And he did not pull his punches whenidentifying the enemy. "Perhaps worst of all,these problems originate primarily frombiologists," he wrote on his website, referringto the fact that many wildlife managers workon the assumption that wolves can withstandheavy culling because they breed quickly.In Alaska, up to 50 per cent of wolves areshot or trapped every year, with little effecton their numbers. But Haber argued thatby focusing on population size, theestablishment has ignored the fact thatthe hunting of wolves warps their socialstructure, ripping apart the family ties andtraditions that define wolf society."Gordon was an aggressive personality, andhe took on the scientific dogma about wolves,"says Douglas Smith, leader of the YellowstoneWolf Project. Despite many thousands ohours spent in the field, Haber publishedlittle peer-reviewed documentation of hiswork. Now, however, in the months followinghis sudden death, Smith and other wolfbiologists have reported findings that supportsome of Haber's ideas.Once upon a time, folklore shaped ourthinking about wolves. It is only in the pasttwo decades that biologists have started tobuild a clearer picture of wolf ecology (see"Beyond myth and legend", page 42). Insteadof seeing rogue man-eaters and savage packs,we now understand that wolves have evolvedto live in extended family groups that includea breeding pair – typically two strong,experienced individuals – along with severalgenerations of their offspring.Building on this insight, Haber arguedthat older wolves pass knowledge down toyounger pack members, and that humanhunting disrupts this natural order. Lonesurvivors or pairs without supporting familymembers behave more unpredictably andkill more large prey animals than wolvesliving in stable packs, so hunting is oftena counterproductive way of trying to managwolf populations. His claims have beendifficult to prove, partly because few cornersof the Earth hold undisturbed wolf habitatwhere they can be tested.Yellowstone National Park, locatedprimarily in Wyoming and also in parts ofIdaho and Montana, is one of the exceptions.Grey wolves were reintroduced here in 1995,following a 70-year absence that resultedfrom intense predator control measures inthe early 20th century. The population nowthrives, and in recent years it has become clearthat packs there are different from those inareas where wolves are regularly killedbecause of conflicts with people or theirlivestock. Outside the protective boundariesof the park, few wolves live more than threeor four years, and a pack seldom includesmore than five or six individuals. WithinYellowstone, wolves tend to live longer – somehave survived to be more than 10 years old –and they sometimes stick with their pack into their fourth or fifth year, a phenomenonnever before recorded.
Wolf family values
Few places remain
where wolves can live
as nature intended
The exquisitely balanced social life of the wolf has
implications far beyond the pack, says
G
" Long viewed as a gang ofcompetitive thugs,a wolf pack is actually anextended family"
"Such packs do things very differentlythan the much simpler packs found inhuman-dominated landscapes," says Smith.When it comes to hunting, for example, thereis a division of labour between the sexes. Thefleeter females test herds of elk by rushingthem at high speed, to find the weakesttargets. Then the heftier males attack and killthe prey. Such skills clearly require practice:during a decade of intense wolf-watching,Smith and his colleagues have documenteda learning curve among young wolves (EcologyLetters, vol 12, p 1). Yearlings are already at80 per cent of full size, but the ability to takedown an elk peaks at age 2, while the ability tochoose the right elk to go after – the greatestintellectual challenge for wolves on the42 | NewScientist | 12 June 2010hunt – doesn't peak until age 3. Smith believeshunting skills are learned by watching olderpack members, and from experience.Comparisons between Yellowstone andareas where wolves are not protected alsosupport Haber's contention that smallerpacks tend to kill more prey animals per wolf.A group of five or six wolves cannot eat anentire elk or moose in one sitting. They will filltheir bellies and then rest and digest, leavingscavengers such as ravens, eagles, coyotes andgrizzly bears to attack the carcass. "They onlyget one feeding on it," says Smith, "so they willgo and kill another animal to feed themselvesagain at the same pace as a pack that's gottwice as many animals."
Biological Conservation, vol143, p 332). The team also observed a rapid shiftin wolf social structure. Before the ban, fewanimals survived to the age of 5 and a typicalpack comprised a handful of unrelatedanimals. A decade on, packs are now made upof a breeding pair – an unrelated male andfemale – and two or three generations of theiroffspring, just as in Yellowstone.This transition to more stable, family-basedpacks has been accompanied by a shift in diet.Before 2001, wolves would seldom attempt totake down a moose, even though moose are prevalent in the Park...............Now, they dine on both deer and Moose. " Allowing wolves to express their naturalsocial behaviour benefits ecosystems"
The contrast in behaviour between huntedand protected wolves is emerging from studiesin another area too. In Algonquin ProvincialPark, Ontario, Canada, eastern wolves havebeen protected for more than a century.Nevertheless, hunting in the surroundingtownships was causing around two-thirds oftotal wolf deaths, primarily in winter whentheir main prey, white-tailed deer, roamedoutside the park in search of forage. Then in2001, hunting on the outskirts of the parkwas banned. Since then, Linda Rutledge, ageneticist at Trent University in Peterborough,Ontario, has led a team tracking changes inthe wolf population.Their recently published results reveal thatfollowing the 2001 ban, the number of wolvesin the park held steady as more animals diedof natural causes (
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