Reprinted from the Oshkosh Scene newspaper with additional photos of cane beds and birds that nest in them.
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The East Channel Canes on Lake Poygan may seem to have a strange name, but once upon a time there was a corresponding West Channel Canes, and even more surprising is this is the place where the Wolf River used to empty into Lake Poygan. Now these few scattered cane beds are all that remain of a huge wetland complex destroyed by flooding, waves and ice. Without restoration these too will be lost. |
On the Lake Winnebago Upper Pool lakes there is a rare
habitat called cane beds that are popular fish, wildlife, and the human
enthusiasts that follow them. These beds
are composed of a native strain of
Common Reed (Phragmites australis). Our
native strain is an important part of Wisconsin’s wetland ecosystems, but there
is a variety originating from Europe that is highly invasive. These aquatic plants are the remains of
wetlands lost since the damming of the
Fox River in the 1850’s. Where it was firmly rooted it survived the
breakup of the surrounding marsh and the near permanent flooding. Although they are tough plants, and survived
the high water, they too have been slowly fading away.
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Forster's Tern chick hiding in reeds |
Historically several of the cane beds have been used by
colonies of the endangered Forster’s Tern.
If you have never seen a Forster’s tern, picture a gull and cross it
with a jet fighter. These birds are fun
to watch. Terns will cruise around the
lakes searching for small fish, and when a bird spots one it begins to
hover. Then locked on its prey, the tern
drops from the sky, wings partially folded back, and plunges into the
water. The bird briefly disappears and
then flies up and away. Depending on the
time of year the tern may give the fish to its mate, or one of its chicks. These terns are endangered because their nesting
habitat, floating mats of vegetation, are no longer that common. On the Winnebago Upper Pool Lakes, the cane
beds have shrunken and so has the Forster’s Tern population.
click below to see more of the cane beds
Why are the cane beds disappearing? The main reason is they really don’t belong
where they are. Common reed grows best
on wet, but not flooded wetland soils, not in standing water year after
year. In such waters they are vulnerable
to ice, wave and flood damage. It is
obviously important not to break off living stems of these plants in deep
water, but what is far less obvious is that it is equally important not to
break off dead stems. The dead stems act
as breathing tubes and drive oxygen down into the roots were it is especially
needed in early spring before the plants send out green shoots. Driving a snowmobile through the beds in winter
or a boat in spring breaks off the stems at or below the waterline and the lack
of oxygen to the roots stresses or kills the plants.
If you enjoy fishing the canes, stay out, motor around and
fish the edges. If you duck hunt, never
run your motor through the canes, and take care to damage as few stems as
possible while concealing yourself. If
you enjoy swimming near the canes, never tie your boat up to or throw an anchor
among them. If we take care of them they
will last longer, but they require management beyond individuals being
kind. Water level management needs to be
changed to allow for better growth, and sediment that has washed away over the
last 160 years may need to be returned.
Only with proper management and respectful use will they last another
160 years.
Photos of bird nests in the cane beds:
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American Bittern Nest and Eggs |
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Injured Forster's Tern, this tern was taken to a wildlife rehabilitator but later died. |
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Yellow-headed Blackbird nest and chicks, tipping over as cattails bend |
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Forster's Tern Nest and Eggs |
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Lake Butte des Morts cane bed east of Terrell's Island |
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