Washington shifts lion hunting strategy
It was a warm, early September day as eleven-year-old Simon Impey picked berries with his juice-stained fingers and popped them into his mouth. He was suddenly knocked to the ground, and his mother heard him scream as the jaws of a mountain lion clamped around his skull. Wielding her water bottle as a club, Simon’s mother mounted a desperate counterattack, convincing the cat to release him and flee. She rushed Simon to the hospital, where he eventually made a full recovery. The lion was never found.
Various studies have shown that younger cougars—adolescent males in particular—are responsible for most human confrontations and livestock depredations. In 1996, Washington voters passed I-655, banning the use of hounds for cougar hunting across the state. To compensate for the anticipated decrease in harvest, game managers increased season lengths and limits, and offered mountain lion tags bundled with deer and elk licenses.
The tactic succeeded. Hunters have since killed an average of 225 lions each year, compared to 157 per year in the six seasons preceding the ban. But when it comes to managing the number of young cougars in an area, it might be less about how many lions you kill, and more about which ones. Recent findings of an ongoing study from Washington State University’s Large Carnivore Conservation Lab have helped shed light on this, and moved Washington to shift how it manages lion hunting.
Part of the WSU study attempted to lower the cougar population by 25 percent in one area of northeast Washington. Yet because of the surplus lions in the surrounding region, densities remained relatively constant. The population, though, became dominated by adolescent males. Having male teenagers running the show is a recipe for trouble, regardless of species.
In a stable, moderately hunted cougar population, mature male lions occupy a territory that seldom overlaps with other males. These territories can be up to 150 square miles and may overlap with one or more female’s territories. The mature toms protect their turf from encroachment by adolescent males, sometimes killing them and keeping cougar densities across a broad area relatively low, according to Robert Wielgus, director of the Large Carnivore Lab at Washington State University.
But overharvest of adult toms, the prized target of most lion hunters, can cause the cougar population dynamic to shift.
“When an adult male is killed or removed from a population, two or three other males come to the funeral,” says Wielgus. The density of lions may even increase slightly as adolescents pour in to fill the void, and a sort of anarchy ensues. Research found multiple young males sharing the same territory may put increased pressure on local prey populations such as deer and elk, and that male lions killed four times as many adult elk as females. And it’s these inexperienced young guns, desperate for an easy meal, that are more likely to cause problems with humans or livestock.
Wildlife managers in Washington found this research compelling enough that they adopted a new management plan going into the 2012-13 cougar season. “This is on the heels of about 10 to 15 years of research from around the state,” said Donny Martorello, carnivore section manager for Washington Department of Fish & Wildlife. Wildlife managers aim to maximize lion harvest while maintaining stable age and sex ratios by killing 12 to 16 percent of the total lion population annually across every sex and age category. For some areas that equates to an increase in lion hunting, and a moderate reduction for others.
Managers say this change won’t likely lower the number of lions killed by hunters statewide, but should act to better distribute the harvest, taking some pressure off overharvested areas that had become dominated by sub-adult males, and increasing hunting in under-subscribed units.
The new strategy also breaks the state into 49 cougar hunting units based on distinct cougar populations. Once hunters kill 12 percent of the total lion population in a given unit, the district biologist and game managers analyze the harvest in terms of age and sex ratios. At that point they can either shut down the unit for lion hunting (although in the 2012-2013 season, no cougar hunting seasons were shut down at the 12 percent threshold), or continue it. As harvests approach 16 percent, managers consult again. It’s incumbent on hunters to keep careful track of which units are opened or closed and to report
Using this method, managers are hoping to leave enough mature toms in the field to regulate the unruly youngsters. Admittedly, no wildlife management system is perfect, and biologists are open to revisions of the regulations.
“We don’t have a crystal ball,” says Martorello. “We’re going to try this for a few years. If one of the dials is off somewhere, if we’re not calibrated quite right, we can still fine-tune it in the future.”
The Rocky Mountain Elk Foundation continues to believe that managed hunting plays a vital and proven role in effectively balancing wildlife populations, predators included. Mountain lion populations have grown substantially alongside deer and elk populations in many areas, helping to show the value of careful management. Statistics also show that attacks on humans are most common in areas where mountion lion hunting is prohibited. Hunting regulations reflect the latest and best science, and the beauty of state management is that it can test new theories and adapt to unique local circumstances. RMEF will watch with interest how well Washington’s new cougar hunting management plan works for that area.