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 Read about
different kinds of predators:
eagles,
wolves,
sharks,
rattlesnakes,
frogs,
tarantulas,
and many others. Visit often because new species will be added regularly.
Predators and Ecosystems
 Predators
can have a stabilizing effect on an ecosystem, a characteristics of a
healthy ecosystem. A modeling study by the
Conservation Science Institute
found that large sharks in the
North Pacific Ocean create a more stable system. However, if
the sharks are removed from the system, such as resulting from a shark
predator control program, the model predicts adverse and sometimes
non-intuitive consequences. Once the large sharks are removed, smaller
predators such as arrowtooth flounder and halibut are released from the
sharks' predation effect and their populations expand. The flounder and
halibut consume smaller forage fish (high-fat fish important to many marine
predators) that would otherwise be eaten by endangered sea lions and
seals. Commercial fishing closures would likely result to protect endangered
sea lions.
Large predators
can have a positive impact on ecosystems. Wolves chase their prey until they
find an animal that is weak. This is very different from the opportunistic
way coyotes generally hunt, they take whatever crosses their path. Wolves
are also pack hunters who hunt cooperatively and whose populations respond
very quickly to increases or decreases in prey availability. Coyotes are
more individualistic, hunting in smaller units and responding very quickly
to increases in the prey bases and very slowly to decreases due to the
adaptability of their hunting skills. As a consequence of their different
behaviors, they have different impacts on their prey. Wolves tend to
eliminate the old, sick, and genetically inferior animals from populations
while coyotes, bears, and cougars tend to take animals without regard to
their condition.
Large predators
control smaller predators. When wolves are eliminated coyote populations
explode. Likewise, when coyotes are removed, foxes prosper. The overall
result is an increase in the impact of predators on prey. Researchers have
estimated that each reintroduced wolf pack (10 wolves) in Yellowstone will
displace 50 coyotes. It's easy to see that impacts to prey populations will
be less from 1000 pounds of wolves than 1750 pounds of coyotes.
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