A WALK IN A SOUTHERN STREAM
September 16, 2002
I saw the bullfrog sitting up in the bush with all the flowers, I
knew the trip had been worthwhile. That's the great thing about getting
out in the woods in autumn before the cold spells hit. Animals and
plants abound, and you never know what you might see.
was with John Jensen, the herpetologist with Georgia's Department
of Natural Resources, and Kurt Buhlmann, the turtle specialist with
Conservation International. Since all of us were overdue for a field
trip, we decided to take an excursion out to a coastal plain swamp
in South Carolina. John wanted to catch a rainbow snake, so that became
our mission. Searching for the rare and beautiful rainbow snake is
always a good excuse for an outing. When we saw the bullfrog we were
wading shin deep in a clear, woodland stream, a tributary into the
swamp. We were not really lost, I explained, because I was sure this
particular stream came out near a dam where it flowed over a spillway.
An hour or so before, I had admitted that I was not sure how far upstream
the dam was.
trekking along in a crystal clear, sandy-bottomed stream on an almost-cool
autumn day can be delightful and make you glad you got out of the
office. Numerous plants bloom in the fall, and most streamsides in
the South are adorned with shrubs and solitary plants with sweet-smelling
flowers. We saw bright red cardinal flowers along the stream's swampy
margins. Shrubs with perfumy cream-colored flowers were on the higher
banks. Yellow composites of different sorts were in the drier areas.
My glance toward one of the flowering shrubs brought the amazing sight
of the bullfrog.
was the first time any of us, all experienced herpetologists, had
ever seen a bullfrog sit high in a bush, fully five feet above the
ground, but there it was. We all knew that just because we had never
seen such a thing before did not mean it was not a common event. And
being ecologists, we assumed there must be an explanation. Within
minutes, what we decided was part of the explanation flew into view.
wish I could say we actually saw the event we assume occurs when bullfrogs
perch in bushes (something, you will remember, that none of us had
ever heard of or seen). However, we can speculate based on circumstantial
evidence. Let me show you how the science of ecology sometimes works.
we looked at the enormous bullfrog (probably almost a foot long when
stretched out) perched majestically in the top of the bush, Kurt pointed
out a cardinal flower growing nearby. I commented that cardinal flowers
are one of the last natural feeding sources for hummingbirds that
migrate south during this season. As I said this, Kurt pointed above
the bush and said, "and there one is." A hummingbird zipped
into view above the flowering bush, hovered for a moment to watch
the three of us standing in the stream, and disappeared. John then
noted that "maybe the bullfrog is sitting in wait for a hummingbird
did not see the bullfrog eat a hummingbird, but I have no doubt that
it had climbed into the bush to sit amid a smorgasbord of birds and
insect prey. I looked upstream to the next bush like that one and
noticed it was covered with butterflies, as this bush had probably
been before we three humans blundered onto the scene. The bullfrog
was simply doing what frogs and other animals spend most of their
time doing-looking for something to eat. And bullfrogs have been documented
to eat everything from birds to small snakes to baby alligators.
never did see a rainbow snake on that excursion. But sighting the
bullfrog was its own reward. And it reminded us that the unusual and
unexpected may be encountered in nature at any time. You don't have
to get lost in a stream; you just have to walk outside and look around.
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