Attenuated
opportunities for effective wildlife protection due to rapidly changing climate
Joseph Siry
Rollins College, Winter Park,
Fl.
Save the Manatee Club,
Maitland, Fl.
Biological
diversity or the species richness, habitat variety and genetic variability of
plants and animals will change regionally due to climate change. But to what
extent and to what degree of damage remains difficult to know with great
certainty for three related reasons. The pace of change being the swiftest in
10,000 years, and the abruptness with which the shift since 1950 has occurred,
and the level at which carbon dioxide has accumulated is unprecedented in the
past 650,000 years. Currently there are signs with respect to wildlife impacts
in the Arctic and Antarctic, the Central American isthmus and among mountain
terrains in the Great Basin where observed patterns of abundance of flora or
decline in fauna provide a suggestion of what may come. But there are no
predictive patterns that emerge aside from case specific responses of mammals,
amphibians, butterflies or flowering plants to new temperature and rainfall
patterns.
Studies
clearly reveal that soil moisture, average temperature changes, frequency and
abundance of precipitation, and an advance in the onset of spring in the
northern hemisphere are all persistent physical patterns that do not reveal in
their pronounced abruptness or accelerating rate any natural trend. Further the
biotic responses associated with observed changes in the range of butterflies,
or abundance of amphibian species, or sufficient prey for sea lions, penguins
or polar bears indicate that an abrupt shift is underway to which large animals
and older plants will have to adapt. Furthermore there is now a scientific
consensus that the heat absorbed by the oceans will continue to affect the
planet for some decades to come. Those influence are
most likely to accelerate, if present trends continue, after 2050. These
impacts, as manifest in ocean thermal expansion causing sea levels to rise,
will also include a shift in the frequency and abundance of rainfall
away from the tropics toward the polar latitudes. Existing studies show that
some strategies among mammals are adaptive under rapid changes in thermal
patterns, but other strategies are not. This means that broad generalizations
fail to capture the enormity of the range and the subtle variation in
adjustments now observed among species.
What
appears certain is that adaptations will occur. Some competitive advantages may
expand or reduce ranges and numbers of populations, as certainly the isolation
from one breeding population to another will change for desert, savanna,
forest, and mountain species. In addition the customary timing in the
appearance of flora necessary for the breeding, feeding, or migration of
specialized organisms will more likely favor the adaptive generalist in the
quest for food, shelter but that reproductive success may rely on different
traits that favor endogamous mating habits among animals.
By
looking at current practices and proposed recommendations for wildlife and
fishery conservation based on existing insect, amphibian and mammal studies,
the paper presents a series of critiques of widespread complacency with respect
to protection of terrain and management of water resources essential for the
continuation of certain keystone, and significant indicator, or sentinel
species.
February
5, 2007
J.
Siry