Whenever a game species drops off precipitously, it's easy to lay the blame on predators. Easy, perhaps, but only in rare cases is it totally accurate.  Short-term losses are more likely weather related, and long-term declines are almost always tied to habitat degradation.

   But there are exceptions, when predators take a high a toll on a particular prey species, and this might be the situation with our southeastern elk right now, particularly for the Blue Mountains' Wenaha herd, an interstate band we share with Oregon.

   "Our elk calf survival has gone up slowly, but it's not nearly as high as it should be, right around 35 calves per 100 cows," said Pat Fowler, state big game biologist for that area.

   When I asked Fowler what was responsible for this low number, Fowler wasn't ready to lay the total blame on predation, either from cougars or bears, but he did acknowledge that plenty of cats roam the area right now and encouraged me to check out research being done in northeastern Oregon and an earlier Washington study.

   Facing low elk numbers in several northeast and southwest sites, Oregon's Department of Fish and Wildlife came up with a plan to capture and radio collar a number of cow elk, calves and, with the use of hounds, cougars. Calf mortality would be monitored for two years, and if 50 percent or more died, 30 percent or greater due to predation, the cougars would be reduced by 50 percent in one of two side-by-side sites.

   Then if calf survival increased significantly on the site with less cougars, their impact would be fairly clear. However, if it didn't, then the study would have to chalk it up to what the biologists call "compensatory mortality" — death that would have occurred anyway due to other factors, most likely nutrition.

   However, before this study could move forward a lawsuit was filed, and a federal judge ruled that an environmental impact statement would have to completed before any cougars could be killed. Oregon officials decided against that costly procedure.

   "It meant collecting much more data over a longer period of time," said Bruce Johnson, a wildlife research biologist in charge of this study.  "What we know now is that cougars are responsible for the majority of the elk calf mortality, around 70 percent.  The Wenaha herd, which once had a population of about 4,200, has been down around 1,500 and isn't coming up very fast.  There may be a relationship between the carnivores and elk density, but until we have all our data in and can crunch all the numbers, I'm not ready to make that statement."

   And neither Johnson nor any other game manager is blaming cougars for the initial precipitous Wenaha decline. Prolonged droughts, damage-control permits, one very bad winter and years of fire suppression were the major culprits. But the question is, particularly after several major burns in recent years have opened up 150,000 acres of fresh elk habitat, are the big cats now keeping this herd suppressed?

   "One argument has been that the cows are in such poor condition, that it's a lack of nutrition that is killing the calves, and our study looks at all that," Johnson said. "That question still hasn't been fully answered, but in terms of predation, even a healthy calf doesn't have much of a chance once a cougar locks onto it."

   A predation study was also conducted on the Washington side of the Blues, this one from 1992 through 1997, a period when 224 elk calves and 89 cows were radio collared and monitored.

   "We found about a 54 percent calf mortality during that period, which really isn't that bad," said state wildlife research biologist Woody Myers. "Seventy-seven percent of those losses were due to predation, mainly to cougars.  Black bears and coyotes get some early on. After July, though, only the cougars can still prey on elk calves effectively.

   "Bears hunt by smell, mainly in the calving areas, but cougars hunt by sight, and even after the cows form protective herds of 10 to 50 animals, they can use their stealth and speed to charge in and kill a calf."

   If today's elk calf survival suddenly climbed back to that 50 percent level throughout the Blues, the question of excess cougar predation would largely disappear.  But when it's down in the low 20s, as it's been for the Wenaha elk and other herds in the Oregon study, then wildlife biologists, sportsmen, and the communities that rely on hunting-generated revenues all need to look honestly for the reasons why.

Leroy Ledeboer is a retired community college teacher and a licensed Alaska fishing guide. He can be reached at 765-6657 or ledeboer@nctv.com.                                

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