Pika enthusiasts have reason to celebrate this season, as new survey data from Cascades Pika Watch shows numbers of the potato-sized mammals — and the volunteers trained to spot them — are on the rise in the Columbia River Gorge.  Since the 2017 Eagle Creek Fire, surveys indicate the pika population in the area has been steadily increasing.  Last year volunteers spotted pikas at nearly two-thirds of the sites surveyed, and this year that number was even higher.  Pikas, tiny rabbit relatives known for their distinctive, squeak-toy-like calls, typically live on mountain slopes at elevations above 6,000 feet, but a unique low-elevation population is living in the Columbia Gorge.  Every summer, volunteers from Cascades Pika Watch — a program of the Oregon Zoo — head into the field with binoculars to stake out pika hot spots, record their locations and listen for the pika’s telltale squeak.  Then they upload their data to a website, helping biologists to better understand where pikas live and whether their range is shifting.  There is growing concern among scientists about the future of pikas, as climate change has caused population declines and local extinctions in parts of the pika’s range, but the season’s results are very encouraging.