Interactions of peccaries and tapirs on plants, including seed predation, dispersal, and the impact of tramping
Principal Investigator: Harald Beck, PhD
My overarching
research interest focus on understanding how natural (i.e. treefalls)
and anthropogenic disturbances (i.e. overhunting of mammals such as peccaries
and tapirs) affect the population dynamics and species richness of animal
and plant species in the Amazon. My current research in the Amazonia focuses
on various interactions of peccaries and tapirs on plants, including seed
predation, dispersal, and the impact of tramping. For example, the dramatic
importance of peccaries for Amazonian forest ecology is apparent to anyone
who has watched a 300-strong herd of these animals thunder through the
understorey. But across vast sections of the Amazon the species has now
been driven locally extinct by hunters, and a new generation of Amazonian
trees is growing to maturity without the massive seed predation, soil
disturbance, and physical damage wrought by large peccary populations.
In areas where peccaries are extinct, changes in the plant recruitment,
distribution and species richness should occur, but no one yet knows what
those changes are and what mechanisms underlie them. After compiling a
review for a book chapter on peccary-plant interactions and using my field
data, I developed a conceptual model that hypothesizes interactions of
peccaries with plants and other animal species, as a first step towards
understanding how forests are likely to change without peccaries. These
results are not only crucial to understand tropical diversity but will
also help in developing new conservation strategies for peccaries. To
test the model, I have set up several long-term experiments including
over 200 exclosures in Cocha Cashu and Los Amigos (at two pristine field
sites, separated over 200 km, in the Peruvian Amazon.
Other research projects include experiments on different modes of seed
dispersal, predation by peccaries and tapirs. For example, germination
tests on seeds obtained from fecal matters of peccaries and tapir indicate
that peccaries disperse only small seed of plants, whereas tapir disperse
seeds of large and small sizes.
One question
we (the IUCN Tapir Specialists Group), are currently testing is the impact
of tapir trampling on seedling and sapling communities. To address this
question, we have established hundreds of 5 x 2 meter exclosures across
five Neotropical forests and in Malaysia. The results will not only advance
our understanding of tapir-plant interactions, but will also be crucial
for future conservation strategies, i.e. what changes could be predict
in the absence of tapirs or other megaherbivores.
Contact
Harald
Beck Ph.D.
Center for Tropical Conservation
Duke University
P.O. Box 90381
NC 27708
Phone (919) 490-9081
harald@duke.edu
http://www.duke.edu/web/ctc/staff/haraldbeck/haraldbeck.html