| Things to think about Water birds such
as herons and egrets were once almost
wiped out by the millinery trade but made a great comeback once
laws were put into place to protect them from hunting and trapping.
Their current decline stems both from habitat loss, which may
not be possible to reverse, as well as from human disturbance,
excessive predation, and possibly exposure to contaminants and
pesticides, which may be reversible.
· Water birds nest in large colonies and thus need large undisturbed areas for nesting
and breeding.
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Importance
Our
populations of American egrets, night herons, and other water
birds are declining. Water birds are generally at the top of
the food chain, and so their well-being can serve as an indicator
of the general health of the ecosystem on which they rely: in
this case, our wetlands and shore. If water birds are declining,
we can also infer that the species they eat, such as fish, amphibians,
and insects, are also in trouble. This decline is due in part
to the over-development of shoreline areas and wetlands.
Economic
Bird watching is
the fastest- growing outdoor sport in the United States. This
indicator is important to watch not only for the direct contribution
of bird watchers to our economy, but because the habitat that
water birds prefer is also the habitat preferred by vacationers
seeking refuge from a busy world. If this habitat is lost, it
will have other economic impacts, such as additional flooding,
water supply degradation, and weakened fisheries.
Environmental
Water
birds react to many changes in the environment, including excessive
human disturbance or disruption. Their decline alerts us to
many environmental problems, from pollution to habitat loss.
They are good indicators of toxics because they are long-lived,
feed high on the food chain, and are reproductively sensitive.
As a result, they are a "plural indicator species." Declining
populations of indicator species can indicate an ecological
unraveling that threatens our state’s natural capital as well
as the clean air and water provided to us "for free" by nature.
Social
Birds, like all
of New Jersey’s wildlife, are part of our heritage and our memories.
They are part of what it means to explore the back bays, lagoons,
and marshes of our state and to participate in the tradition
of experiencing nature.
Knowledge
Gaps
These data
account for a small number of species in a small section of
New Jersey. We need population data for many other species of
birds and animals for each of New Jersey’s many habitats and
ecosystems. Since water birds are migratory, data are necessary
to account for what happens to them after they leave New Jersey.
A clearer understanding of the factors involved in water bird
population decline would also be useful. Additional data are
needed for this indicator, as this survey has not been conducted
since 1995. However, resources to update the data are being
pursued.
Data
Source: NJ Department of Environmental Protection
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