| Many of New Zealand's indigenous fauna species
have proved to be extremely vulnerable to the effect of introduced
predators. Extinctions of over 50 endemic species have occurred
during the 1000 years of human settlement in New Zealand (Davis
and Malloy, 1994) as a direct or assumed result of predation,
while many others are in continued decline, and without effective
predator control, will also become extinct.
Continued loss of biodiversity is unacceptable. The development
and implementation of reasoned and carefully planned predator
control or eradication programmes
is a vital tool in the suite of management techniques available
to all agencies and individuals attempting to preserve New
Zealand's unique biodiversity.
Predators can also have wider indirect implications for
indigenous ecosystems and ecological processes beyond the
impacts on their immediate prey. For example, the reduction
in pigeon numbers by a predator can have long term implications
for the structure and composition of the forest ecosystem,
by removing or diminishing a key dispersal agent for many
large-seeded tree species such as tawa, taraire, pigeonwood,
karaka, kohekohe, and hinau. In many cases the extent and
seriousness of such broad ecosystem alterations are not well
studied or remain largely unknown.
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