Abstract:
As areas of conserved pristine forest are reduced in size they are increasingly susceptible
to significant immigration of animals and plants from nearby anthropogenic
secondary successional habitats, and the animals of the pristine forest are also likely
to forage outside of the pristine forest in the food-rich secondary succession. This
phenomenon should be of particular importance to the interactions that occur in
natural disturbance sites within pristine forest (e.g., succession in tree falls). However,
since much large tree regeneration begins in tree fall gaps in the canopy, even
the composition of the canopy may be influenced by large bodies of non-pristine
vegetation surrounding the preserved area. From a conservation standpoint, this
emphasizes that in some cases a patch of pristine forest may remain ecologically
intact longer if surrounded by croplands and closely grazed pastures than if surrounded
by extensive areas of secondary succession rich in plants and animals that
will invade the pristine forest. Colonization of a tree fall by Cecropia peltata trees in
pristine forest in Santa Rosa National Park, northwestern Costa Rica is used as an
example. The phenomenon emphasizes some of the ways that small islands of vegetation
may be only poorly analogous to more conventional islands surrounded by
water.
