Cuerici is a private reserve that
includes fragile high-elevation habitats including primary oak forest, a canyon
that shelters an endangered species of palm, and some areas of secondary growth
forest as well. It is tucked in a valley
on the Pacific slopes of the Talamanca mountain range in Costa Rica. The reserve is owned by a small association
on conservation-minded individuals, one of whom is named Don Carlos. The association purchased the land from his
grandfather, some of which used to be cattle pasture but most of that land was
primary oak forest. Now Don Carlos looks
after and maintains the forest and small biological station, as well as his own
trout farm on the side of the mountain.
The water for the trout farm runs down the mountain, flows through the
trout ponds, and then is collected into a filtering basin where the waste
sediments from the fish are allowed to deposit and decompose into a rich
fertilizer for the garden and making sure that the water that flows out of the
farm is not heavily contaminated.
We only stayed at this station for
five days, but there was a lot packed into that short time. Don Carlos led us on a walk through the
different parts of the forest. The first
part went through fast-growing alder trees, which have moved into various
patches of abandoned cow pasture during the last 20-60 years. However, we soon entered an area of primary
growth, meaning forest that has never been clear cut or heavily harvested, in a
narrow canyon. The canyon is sheltered
from the stronger wind experienced by the surrounding oak forest, making it a
distinct microhabitat, full of lush green ferns and tree ferns, and a few small
palms, which look mildly out-of-place high in these chilly mountains. Actually, there used to be a lot more palms
in this forest, but many were cut to harvest heart-of-palm, a tasty and popular
food in Costa Rica. Don Carlos found
just one remaining palm in the reserve, but he has been working on a replanting
project, using seeds from other sources to start saplings back on his farm and
then transplanting them into the canyon so that they have a head start and are
less likely to be choked out by other plants.
Once we climbed up out of the
canyon, we entered yet another type of vegetation. Large oak trees dominated this area of forest
above 2,500 meters, with moss dangling from their branches and bryophytes
clinging to their trunks. Orchid flowers
bloomed high up in the canopy or on rotting logs. The understory was relatively open compared
to in the canyon, but with dense patches of bamboo. The wind roared in the canopies of the oaks
constantly.
Don Carlos explained various
aspects of the forests biology and conservation as we walked, and I was amazed
at the complexity of all the dynamics that affect the forests health and composition. For instance, wind has a huge effect on all
the plants in the forest, increasing evapotranspiration and thus causing plants
to dry out, or even knocking over trees and other plants if it is strong
enough. Don Carlos emphasized the
importance of the oak trees, which block most of the wind from entering the
interior of the forest, and the danger of removing even a few of the
trees. Once there is a gap in the
canopy, the wind is free to enter and can widen the gap by knocking over trees
around it. This effect is worsened by
the fact that the oak roots interlace with their neighbors, and when one is
removed and the roots die this extra support is lost. In addition, the moss hanging from their branches
collects moisture from the fog and clouds, which then drips down onto the base
of the oak trees, and when the wind is too strong it blows the moss off the
trees and farther down the slope.
Another interesting dynamic has to
do with the bamboo, which is unusual in its flowering habits. Each individual bamboo only flowers once and
then dies, and the bamboo in a particular forest time their flowering to occur
together. It varies from place to place,
but bamboo can go 10, 20, or even more years between flowerings. However, when it does, it is an event that
totally alters the forest ecosystem; migratory birds come in great numbers to
feed on the seeds, and when the bamboo dies it makes new space for other plants
like the oak seedlings to get a foothold.
Oak trees grow very slowly, and this dying off of the bamboo might be
the only opportunity for new seedlings to germinate and survive, meaning that
when oak trees are cut, it might take hundreds of years for the oak forest to
recover, if it ever does at all.
It was inspiring to see the
dedication with which Don Carlos has tried to integrate small-scale sustainable
farming with preservation of a fragile ecosystem. It was also interesting to see a private
effort at conservation, which appears to have been very successful at
preserving the area but has also struggled with some financial
difficulties. I am excited to see how
this method of conservation compares with that used at Palo Verde National
Park, the next site we visit and the first one that is publicly owned.
Sequoia Grettenberg
No comments:
Post a Comment