Biologist describes impact of wolves on ecosystem

By JOAN HAINES, For the Chronicle

The gang's all there.

Yellowstone National Park's top predators -- wolves, coyotes, grizzly bears, mountain lions and foxes, along with photographers, wolf watchers, and wildlife specialists are all featured in Jim Halfpenny's new book, "Yellowstone Wolves In the Wild."

A wildlife biologist, who lives in Gardiner, Halfpenny describes the wolves' impact on other predators in the ecosystem.

"There have been seven books on Yellowstone's wolves," said Bob Crabtree of Bozeman, chief scientist for the Yellowstone Ecological Research Center. "This is the first on what wolves have accomplished, how wolves interact with other species."

Halfpenny has taken some of the most dramatic and significant scientific facts about wolves gathered since their reintroduction into Yellowstone Park in 1995 and put them in easy-to-understand language. Since reintroduction, their population in Yellowstone Park at the end of April 2002 was estimated at 200. Their numbers in Montana, Wyoming and Idaho had shot up to 663 as of last winter, and may include an additional 150 pups born this spring.

The Wolf Recovery Coordinator for the U.S. Fish and Wildlife Service, Ed Bangs of Helena, called the book "pretty outstanding and very accurate."

National Park Service research, conducted by a team headed by Doug Smith, is the framework for the book, he said.

Halfpenny "puts all the scientific research into common language," Bangs said. "He filled in with personal observations. The stories really personalize what happened."

"Jim tells the true tales, chronicling how this top carnivore became established in the world's first national park after a decades-long absence," Smith wrote in the book's Foreword. "Many of the stories are related through the words of the people doing the research, others through the people who watch wolves throughout the year or for weeks at a time."

All the wolf photographs have been taken in the wild and some are extraordinarily compelling. One shows a grizzly sow standing over her small cub to protect it from a wolf attack. Another shows two cow bison charging a wolf to keep it away from their calves.

Several photographers took the pictures, including Dan Hartman, Wayne Kendall, Donald M. Jones and Jess R. Lee.

The book costs $19.95 and is produced by Riverbend Publishing.

Halfpenny discusses which animal is top predator when the predators are hassling over a carcass meal.

"That may depend on several factors including degree of satiation, number of hungry young and number of each species," Halfpenny wrote. "Mothers with young tend to be more possessive. Many wolves may displace a grizzly when one or two would not."

Halfpenny, who holds a doctorate, has written other books about animals, including "Discovering Yellowstone Wolves: A Watcher's Guide," which he authored with Diann Thompson, and "A Field Guide to Mammal Tracking in North America." He has taught numerous wolf classes through the Yellowstone Institute. His company, "A Naturalist's World," provides books, videos, educational programs and slide shows about ecological subjects.

For wolves, killing can be a learning experience. Two packs have learned to bring down bison within the past two years. They killed about 40 bison in the Pelican Valley when heavy snow the past two winters slowed the big animals' ability to get away.

Halfpenny's describes wolves attacking elk from the wolves' point of view.

"A big wolf, a really big wolf, weighs 130 pounds," Halfpenny wrote. "An average bull elk weighs 750 pounds, a cow elk 520 pounds and a calf 220 pounds. Let me put this in human terms. Did you ever pick a fight with someone six times your size? That is what a wolf does when it attacks a bull elk. So wolves compensate by using hunting strategies that include locating, observing, stalking, testing and maneuvering."

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