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By Tamia Nelson May 14, 2002
Beaver ponds are among the jewels of the
natural world. They're reservoirs, absorbing flood waters during years of
heavy rainfall and recharging aquifers during prolonged droughts. They're
settling tanks, trapping sediment and releasing crystal-clear water to
continue its journey to the sea. They're also home to a startling variety
of creatures. Animals and birds are drawn to beaver ponds and the
associated wetlands like metal filings to a magnet. And because wildlife
love beaver ponds, I love beaver ponds.
There's nothing to compare with a quiet paddle around the perimeter of
a beaver pond on a calm, late-spring evening. As the sun sinks below the
horizon and you drift silently through the lengthening shadows, the pond
comes alive. Frogs begin their raucous come-hither chorus. Whitetail deer
escort their fawns to the water's edge for a drink. Turtles drop with a
splash from their daytime perches on partially-submerged logs. An otter
tucks noisily into a fish dinner on the top of the dam. Then, if you've
timed things just right, a full moon rises over the dark fringe of pines,
just as a whole a family of beavers emerges from their lodge, ready to
start the night's work.
North America was once blessed with tens of millions of ponds like
these. No more. Today there are fewer beavers, and far fewer beaver ponds
and wetlands. Happily, though, beaver dams are still a common sight on
canoe-country rivers. That's good. But you only get what you pay for.
Beaver ponds are a delight, but beaver dams can be…well…a damned
nuisance. Dams can be wide or narrow, low or high, but whatever their
size, they can be formidable obstacles, particularly if you're paddling a
kayak or long solo canoe.
Why do beavers build dams, anyway? Simple self-interest. A dam
makes a pond in a river, and the pond makes a moat. Beavers need deep
water to survive, and if the water where they decide to make their home
isn't deep enough, they'll make it deeper. They're a lot like us, really.
They don't accept geography as destiny.
Beavers are eclectic vegetarians. Though they eat buds, leaves, and the
roots of aquatic plants, their favorite food is the inner bark of trees.
Trees grow on land, but beavers are clumsy once out of the water—all
but defenseless, in fact. Water is their element. So they make use of
water to float harvested trees back home, even digging canals deep into
the forest.
And home for a beaver is usually a hemispherical lodge—a spiky
igloo built largely of mud-chinked branches. Surrounded by deep water and
thick-walled, a lodge is proof against all but the most determined
carnivores. Even bears have a hard time tearing their way into a beaver's
house.
Lodges vary in size, but they all look more or less the same. Debarked
limbs are smeared with mud and woven into a dome whose base rests on the
bottom of the pond. The roof rises above the water. Sometimes pebbles and
cobbles are incorporated into the walls, further strengthening the
structure. An underwater entrance leads through a short tunnel to a snug,
dry platform. This is the heart of the lodge. While beavers will spend
hours at a time in the water, they need a place to dry off, groom, and oil
their fur. If they get soaked to the skin, they can contract pneumonia.
No beaver can afford to get sick. Beavers are busy year-round. They
don't hibernate. Before winter locks their pond in ice, they store
food—the branches and trunks of trees, with the leaves and bark still
attached—in underwater caches near the lodge. Beavers can hold their
breath for up to 20 minutes. So all winter long, they swim about under the
ice, inspecting their dam and fetching branches back to the lodge for a
hearty meal.
"Inspecting their dam"? Why bother? Self-interest again. Winter or
summer, the dam's important. It keeps the water level in the beaver pond
constant: high enough to conceal the entrance to the lodge, but no higher.
The thick-walled, water-girt lodge is also climate-controlled. Cool in
summer, it's toasty warm in winter. So comfortable is a beaver's lodge, in
fact, that the neighbors sometimes move in. Muskrats and otters often set
up housekeeping in odd corners, where they're tolerated so long as they
don't become a nuisance.
Over thousands of years, beavers have left their mark almost everywhere
in North America. In a sense, they were the continent's premier landscape
architects—until we came along, that is.
The dam was their principal tool in reshaping the land. Beaver dams are
built from the same materials as the lodge. And when pioneering a new
homestead, the dam is constructed first. Using materials drawn from the
"closet of the woods," beavers span a stream and raise a dam. They're good
engineers. Their dams are much wider at the base than at the top, and the
larger dams form a convex arc, bulging upstream and efficiently
distributing stress—just like the dams built by humans. Not
surprisingly, beavers spend a great deal of their time maintaining their
dams. If a dam is breached, they'll work round-the-clock to make repairs.
Beaver dams are models of hydraulic engineering, as well. Water trapped
behind a dam seeps into the surrounding land, keeping the local aquifer
topped up. During the snow-melt-swollen spring run-off, water flows over
the top in a "controlled flood." Later in the year, as undammed
neighboring streams dry up to nothing, a steady stream of clear, cold
water emerges from the base of each beaver dam.
"Clear, cold water." Sounds good, doesn't it? And canoeists often go
with the flow. This is where problems sometimes arise. The beavers keep
the rivers running long after the spring run-off has peaked, but their
dams are a nuisance to paddlers in a hurry.
What's the remedy? A hint: it's not dynamite or a crowbar. It's
both simpler and easier. First, slow down. Simply slow down. Take it easy.
Remember why you're on the river. The trip's the important thing. Elapsed
time isn't. Enjoy the moment.
Second, use your head. There's a right way to negotiate dams, and doing
things the right way will save you both time and trouble. Then you'll have
more time to enjoy the moment. (Call this the Zen of getting around in the
back-country. Speed's not usually important, but efficiency is.)
OK. You're on your way down a river. There's a beaver dam ahead. What
next? Should you wade? NO. The deepest part of a beaver pond is usually
just upstream of the dam. So if you're planning on wading
there—forget it! (The muck at the bottom of beaver ponds in pretty
smelly stuff, too. You've been warned.) Instead, step out onto the dam
itself. If there's an active lodge nearby, the dam will be in good repair.
Even a small dam will support you and your partner, along with your canoe.
But be careful: the ends of beaver-gnawn sticks are sharp. Get the
point? And watch your step. Mud-covered branches can be slippery. (You are
wearing your life-jacket, aren't you?)
Once on the dam, stay there. Don't try to scramble up the banks and
around the dam. Just get out, lift your boat over the dam, get back in,
and continue on your way. Get out and get over. Simple, isn't it? Here's
the drill:
Let's say you're in a tandem canoe. Approach the dam at a shallow
angle, if possible. Stern paddler braces. Bow paddler gets out, finds a
good place to stand, and steadies the canoe. Next, stern paddler moves up
toward the bow of the boat. She steps out onto the dam, too. Together, the
paddlers slide the canoe up over the crest of the dam and then ease it
carefully down the face. (This will require care—and maybe even a
belay—if the dam is a high one.)
Once the boat's back in the water, the stern paddler hangs on while the
bow paddler works his way forward. One he's settled in his seat and
hanging a brace, the stern paddler gets in. A little push, and you're off.
Easy, isn't it?
Easy for some, anyway. Solo paddlers—particularly
kayakers—aren't always so lucky. It's simple if the approach to the
dam is wide enough to permit "docking" broadside-on, of course. But what
if space is too tight? What if you're paddling upriver on a narrow stream,
for example? What then? Do you approach bow-on? How? There's no partner to
hold a solo paddler's boat steady, after all.
Sometimes you can portage around the dam—if the bank's not too
steep or swampy, that is. Sometimes you can paddle far enough up onto a
dam to be able to step out of your boat without falling into the water.
(Sometimes you can't. Hope you brought a change of clothes.) And sometimes
you can inch your way forward on your deck. (Practice this at home first!
It's easiest if another boater rafts up alongside you and hangs on while
you hunch your way along. Be sure your deck's sturdy enough to take the
load before you try it, though.)
Complicated? Yes. A bit. When you're in a kayak, each dam requires a
slightly different approach. There's no universal solution. That's one
reason I prefer canoes to kayaks when exploring in beaver country. But
does this mean you need another boat if you already own a kayak? Certainly
not! Use what you have. Even if you take an unexpected swim now and again,
it's a small price to pay. Beaver-dammed streams are wondrous, fascinating
places. They're well worth the effort needed to get out and get over.
Copyright © 2002 by Verloren Hoop Productions. All rights
reserved.
Getting Around
Get Out and Get Over!
Doing the Beaver Dam Shuffle
tamia@paddling.net
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