Despite setbacks caused by vehicle collisions, the endangered Selkirk Mountains caribou herd is at least holding an even population.
Aerial surveys completed this month as the animals begin heading north to spring range found 46 mountain caribou mostly in the British Columbia portion of the range just north of the international boundary.
That's the same count U.S. and Canadian biologists compiled last spring, but up from 33 counted in 2004.
The herd's recovery range covers 2,000 square miles.
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Only 1,200-1,400 mountain caribou still roam the planet.
"Five of the 46 were classified as calves, for a recruitment rate of 11 percent, again the same as last year," said Wayne Wakkinen, Idaho Fish and Game Department caribou specialist based in Bonners Ferry.
"The recruitment rate is fairly low, but it's always low for a woodland caribou population. They are reliant on high adult survival. Evidently adult survival is holding up pretty good for the population to be slightly growing to stable."
Of the 46 caribou, three were spotted in Idaho near Little Snowy Top Mountain. All others were in British Columbia, where one group numbered more than 20.
"The count of 46 is somewhat encouraging, because we know three caribou were hit and killed by vehicles on BC Highway 3 this year," Wakkinen said.
Actually, cars took a toll of at least four caribou. Reported accident included two adult males killed earlier in separate collisions, plus one pregnant female killed on March 19.
"That's a big hit," Wakkinen said. "Just like that, we get no increase for the year.
"The numbers have been pretty tenuous, but at least the trend has been in the right direction."
The big setback in the late 1990s was predation caused by cougars that apparently were peaking in population, he said.
"With a lower density of lions, we've had higher adult caribou survival."
U.S. and Canada officials have been trying to address the road kill issue, which has plagued the caribou.
"After the road was built in the '60s, all kinds of caribou were getting whacked by vehicles," said Trevor Kinley of Invermere, a Canadian wildlife consultant who served on the caribou recovery science team.
"The numbers are lower, and some people speculate the caribou were learning to avoid cars. But the road goes through some extremely good habitat of widely spaced old subalpine forest that carries a lot of lichen.
"The area around the pass is the most reliable spot in British Columbia for seeing mountain caribou. During winter, they're commonly right up at the pass or down the east side a ways. That's where vehicles tend to hit them, toward Creston a mile where cars pick up more speed."
Road salt also seems to be attractive to them, Wakkinen said.
"We've talked about hanging bags of salt in the trees off the highway to lure them away," he said.
Caribou population declines likely resulted from a number of factors, including destruction of old growth forest through logging, development and wildfire, experts say.