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FrontRangeLiving.com -> Outdoors -> Cooley Lake
 Waterfowl at
South Platte Park
Each
spring, college students head to Florida or other southern climes to soak in the
sun and water. Birds do, too, and the luckiest will head to South Platte Park,
where a kingdom of waterfowl cruises placidly on a wide lake in the middle of
suburbia.
The
1965 flood that created a bird haven at Barr Lake in Brighton also flooded homes
in Littleton. In response, engineers channeled the river, doing away with its
original riparian environment. It's worthwhile to take a look at both lakes,
because the channeling now invites ducks and geese rather than the variety of
smaller songbirds birds found at Barr Lake. And the warmer waters that flow from
dammed water invites ducks to stay later and arrive earlier. It’s a lesson in
both engineered and natural riparian environments.
"Ducks
are great to start with if you are interested in birds," a volunteer guide
says as we set off for a hike, "They're large and don't spook easily."
Ducks and geese also are visually striking, which makes them easy to point out
to the birding novice. Black and white coats with a dash of iridescent green or
vivid red always provoke an outcry from the group. Today we'll see gadwalls,
American widgeons, a great blue heron, belted kingfishers, buffleheads,
pied-billed grebes, a northern pintail, common merganser as well as the usual
Canada geese and mallards. While songbirds may be recognized by their sounds,
these waterfowl, once caught in the scope, will show off their plumage.
 Owned
by the city of Littleton, South Platte Park's Cooley Lake is 230 acres of water.
Once a gravel pit in the 1950s, the 1965 flood not only changed the terrain, but
forced citizens to consider how best to stem flooding and preserve some natural
beauty. Years ago the river flooded periodically, which fostered a lush
cottonwood forest and thousands of songbirds like warblers, nuthatches, catbirds
and sparrows. "Today we have a totally different system," a resource
specialist says, "we have a declining cottonwood forest and a loss of
riparian birds. The winners, however, have been the waterfowl. They have joined
the raptors like eagles and hawks."
Altogether,
the park meanders for 2 and a half miles, an overall size of 50 square miles
with 150,000 human residents and 230 sighted species of birds. Bordered by a few
horse farms and housing developments, a hike is scheduled each month. The path
is opened only on that one day to minimize the impact on such a fragile
environment but allow the curious to wander close to the lake.
Our
guide takes us out with a scope slung over one shoulder and a bird guidebook on
hand. She helped with the bird census, joined the nest box program, contributed
to the Colorado breeding bird atlas and now guides a group of 20 down a path
toward the lake. A coyote slinks behind us, heading for cover in tall grasses.
"I
got into birding by accident," she says, "I think birds are
fascinating animals. When you think of all the things that go into a creature
that flies--they don't have arms, most have hollow bones, just the right
musculature. They can't have teeth--those are too heavy. Consider their feather
maintenance, feeding their family and slight weight. Even a large eagle doesn't
weigh much if you put them on scales. Yet, birds are everywhere. You can take a
walk in your neighborhood and see lots of birds. That's not true with other wild
creatures."
A
devastating disease can make even the most ordinary bird more welcomed. We spy a
magpie and her face lights up. "We lost so many of them last summer. They
were particularly affected by the West Nile Virus," she says. Some
scientists believe at least 80 percent of the magpie population may have died.
To see them rebound is testimony to their grit and endurance. But they are not
the main draw today.
 We
are headed to the hundreds of bobbing birds on the lake. One grand attraction of
the lake is a warmer temperature than a natural lake. Because water flows slowly
from Chatfield Dam, the temperature is warmer than an icy river filling a body
of water. That prevents the lake from freezing solidly and waterfowl flock to
the 38-degree water, often staying year round when they might have migrated in
previous years.
Historically
there would have been more freezing. But it's not overpopulated yet. Since
predators like the coyote keep an eye out for a fat duck or goose, the birds
rarely stray onto the grassy knolls. Canada geese must eat grasses nearly
constantly and would rather head to a golf course than tangle with a predator.
Also, the summer grasses at the water's edge are not the choice of menu for the
geese. That's fortunate because overpopulation leads to disease.
Most
ducks feed on grasses; that's why they're upended with tails in the air as they
snatch a tasty weed. These birds will eat their fill, become fat and sleek as a
way to store energy for a long migration. Many will head to South or North
Dakota, Montana or Canada as the weather heats up.
As
we search for a common goldeneye or gadwall, it's easy to see why ducks have
been a favorite meal in nearly every cuisine. With their plump bodies and slow
waddle, they're hardly the darting miniatures that make up many birds. Even so,
mallards are a successful species, judging by their numbers. That may be because
they are generalists--not linked to a specific food or terrain. Generalists
often can adjust to environmental changes more easily than other kinds of
species.
That
explains why ducks will follow people for a handful of breadcrumbs, despite the
fact that bread won't contribute to waterfowl health. In the duck cafeteria,
mallards eat grubs and a wide variety of plants, all in the quest to put on
weight. To fly long distances, they line up in a tight V-formation to take
advantage of aerodynamics. A hearty population is linked to water and abundant
greenery at the bottom of ponds. These birds increased in the 1990s when we had
very wet years. There has been a drop since then, attributed to the drought of
the last few years.
Bird
watchers note striking differences each year. One year the common goldeneye
ducks arrived in mass. The next year, few showed up. You can be assured of about
40 species each year, but exactly which species is harder to guess. Most birders
say they notice what comes in rather than what is missing. And that’s what
keeps longtime birders returning each month.
In
the meantime, someone spots a red-tail hawk, circling above a tree on the other
side of the lake. A female hawk sits in a nest, hawk profile prominent through
the lens of the scope. "She's taken over the bald eagles' nest," an
experienced birder suggests. "They nest early. They could have babies by
now." We pack up the scope and head back to the nature center after one
last look at the grebe, which dives again and again for tiny fish. The grebes
look like little swans, a birder observes. A belted kingfisher swoops by and our
guide smiles: "That's our mascot," she says, about a small black bird
with a comical topknot.
By
May, as a few songbirds move in, some quacks will be replaced by trills. The
shore birds will be scurrying about as raptors soar above. Only a few of the
water birds will be bobbing on the lake, the majority will have moved on. Next
year will bring another group with a shift in population, and perhaps the common
goldeneyes will return.
 South Platt Park,
Littleton Parks and Open Space
Directions: From south Denver (E-470 and US-85), proceed
north on US-85 (Santa Fe Drive) for 1 mile. Turn west at Mineral Ave and take an
immediate right at South Platt River Parkway. The park’s Carson Nature Center
is one block up on West Carson Drive, at 39.5831N, 105.0287W
Features: The park features a 2-mile nature walk between
Cooley Lake and the South Platt River. Dogs permitted, on leash. But on guided
tours, best to leave the dogs at home.
More
Info: Carson
Nature Center, 3000 West Carson Drive, Littleton, CO 80120, 303-730-1022, http://www.littletongov.org/parks/ssptimeline.asp.
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