Invasive Species
Exotic plants and animals that are introduced into the local environment, either purposefully or accidentally, pose a serious threat to our estuary’s living resources.
Freed from the natural system of checks and balances in their native habitat, some exotic organisms thrive, and are able to reproduce explosively. They then invade their new environment, and their unchecked growth can cause significant problems for local creatures and habitats.
The Barataria-Terrebonne Estuary is a rich ecological system. It has a mild climate and abundant rainfall, giving many exotics a greater chance to thrive and become invasive.
Exotic
aquatic plants can be a particular problem for the Barataria-Terrebonne
system. Dozens of exotic plant species are already established in the
Barataria-Terrebonne system. These exotics can impede water flow, block
navigation, and clog structures such as drinking water intakes.
Floating or submerged invasive plants can change the vegetation
community structure and species composition in a body of water by
impacting food availability, sunlight penetration, dissolved oxygen, and
other aspects of water quality.
Exotic aquatic plants are not the
only invasives posing a threat to the Barataria-Terrebonne system.
Introduced animals such as the nutria (Myocaster coypus) are also
causing major problems to the environment. The nutria is a voracious
herbivore that destroys trees and consumes marsh plants, often all the
way down to the roots. This exposes soil to erosion and accelerates
land loss. Nutria populations were once held in check by trappers who
sold their fur pelts. But the collapse of the fur industry has led to
an explosive increase in their numbers, and a corresponding increase in
the rate of coastal land loss.
Once
established, it is nearly impossible to eradicate invasive species.
Scientists and officials have developed management techniques to keep
the ecological damage from invasives to a minimum. These techniques
include physical removal of the organisms, control with herbicides or
other chemicals, introduction of specific biological agents, and
legislation to control the sale and spread of potentially invasive
organisms. Only through awareness and vigilance can we respond rapidly
enough to prevent future invasions.