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for people who care about the West

Those buck-tooth dammers are back, big-time


"Nine degrees," I called out, thigh-deep in the beaver pond.  On the bank, foot propped on an aspen log, Sam Bixler recorded the temperature. My other partner, Dave Bolger, called out the water temperature some 60 feet upstream from the slack water of the beaver pond: "Five degrees."

The icy stream was Pennock Creek, elevation 8,500 feet in the Colorado Rockies.  It was week three of Colorado State University's 10-week forestry camp, 55 miles west of Fort Collins.  We'd learn fundamentals of surveying, mapping, timber cruising, ecology, range management and wildlife biology, something that we were already hip-deep in on that day years ago.

Our assignment: "Map and quantify the influence of a beaver colony." Three-person teams were assigned alphabetically; thus, Bixler and Bolger got stuck with Bolsinger. Sam, meticulous, scrutinizing, commented on everything. Dave, curious, objective, patient, was the perfect scientist.  I was a farm boy from Kansas and enjoyed just being there, in the mountains.  As a team, we got along magnificently, the beginning, I assumed, of a long friendship.  But after summer camp I never saw Dave or Sam again.

We measured water temperature and pH, mapped the pond, profiled its bottom and measured the dam and lodge -- a pile of sticks -- then turned our attention to the beavers' activities on land.  They'd cut every aspen within a hundred feet of water but spurned closer Engelmann spruce and lodgepole pine.  The beaver had lugged aspen limbs and small boles to the creek, but large trunks still lay where they were felled, often attached to pointed stumps.  Some standing trees had multiple notches, ranging from near the ground to several feet high, the upper ones apparently made in deep snow. They resembled totem poles, making me wonder: Is that where the idea for totem poles came from?

After mapping and gathering data, we did a fish survey with help from a six-person team that laboriously hauled fish-shocker electrodes and a generator to the site. We learned that 4 degrees' difference in temperature (Celsius) between the upper stream and the pond equated to the difference between trout that grew to six or 10 inches long.

In the mountainous West, swift, cold, snow-melt streams such as Pennock Creek support relatively little aquatic life, and fish are usually few and small. The calm, warmer waters of beaver ponds are biologically richer and support more and larger fish, although global warming may be changing this.

Studies in Washington's Puget Sound Basin by Michael Pollock of the National Oceanic and Atmospheric Administration found that in streams populated by beavers, coho salmon are larger and more plentiful than in streams without beavers.  Pollock believes restoring salmon runs will require restoring beaver populations.

In 1600, an estimated 60-to-100 million beavers lived in North America, coast to coast.  In the 1800s, beaver fur was highly desired for robes, coats and top hats.  Trappers eliminated beavers east of the Mississippi, then looked West. Thus a rodent spurred its own kind of gold rush, creating financial empires and prompting explorations, playing a role in settling the West.

In 1810, four years after Lewis and Clark returned to St. Louis, Wilson Price Hunt's party embarked for the mouth of the Columbia in pursuit of beavers.  John Jacob Astor provided financial backing.

After nearing extinction, beavers began to make a comeback in the early 20th century and are now estimated at 10 million strong, and growing.  Trapping pressure has eased, and, like several other wildlife species, beavers are adapting to urban settings.  In 2007, a beaver, named "Jose," for New York Rep. Jose Serrano, built a lodge in the city's Bronx River, which had been beaverless for 200 years. In Portland, Ore., beavers now occupy Johnson Creek within the city limits, and -- perhaps grudgingly -- they share habitat with feral nutria near Portland International Airport.

Beaver populations continue to increase in Oregon, even though they're still trapped legally.  In addition to all the good things they do -- restoring wetlands, improving wildlife habitat, capturing sediment, reducing erosion and helping to control floods -- they also flood roads and farmland, plug culverts, dam irrigation ditches and cut down desirable trees.

This gets the beavers deported or dispatched; never mind that Oregon calls itself the Beaver State.

What if they flooded my bottomland or cut down my trees? Would I still yell, "Go, Beavers!" as I do at Oregon State football games?   Not likely.   Still, a beaver pond would make a great setting for a reunion of the partnership, Bixler-Bolger-Bolsinger, Beaver Investigators par excellence.   Where are you guys?

Chuck Bolsinger is a contributor to Writers on the Range, a service of High Country News (hcn.org). He writes in Boring, Oregon.

Note: the opinions expressed in this column are those of the writer and do not necessarily reflect those of High Country News, its board or staff. If you'd like to share an opinion piece of your own, please write Betsy Marston at [email protected].