Outbreaks of a rare African strain of encephalitis in the New York
Tri-State area (9/29/99 news
story) have focused attention on the larger issue of exotic
(non-native) species in the U.S. The encephalitis strain is a rare
virus never before been seen in the Western Hemisphere, which has been
transmitted to humans from mosquitoes that have bitten infected
exotic birds brought into the U.S.
Besides spreading disease, exotic species crowd out native plants and
animals, damage crops, and threaten drinking water supplies. Their
presence in the U.S. has contributed to the decline of 42% of the
country's endangered and threatened native species, according to the U.S.
Fish and Wildlife Service, and efforts to control them cost the economy
billions of dollars every year.
Ecologists have been fighting exotic species in the U.S. for decades, but
the battle has been spotty, expensive and largely ineffective. The
specific issue before Congress now is whether new legislative authorities
are needed to address issues of non-native species and their increasing
economic and ecological impacts. The Congressional Research Service Issue
Brief for Congress, Harmful Non-Native Species:
Issues for Congress (April 8, 1999), highlights the choice
between single species approaches and pathway approaches for prevention,
and the choice between prevention and control. It describes existing
federal laws and federal agency roles, and outlines effects, costs, and
issues surrounding 31 selected harmful non-native species.
Whose responsibility is it to ensure the economic and ecological
integrity of the nation in response to multi-billion dollar threats
posed by harmful nonnative species? As the speed and level of
trade and travel increase, the chance of introducing unwelcome
species such as zebra mussels, melaleuca, fire ants, or Formosan
termites increases, but federal activities in this area remain
unfocused. The specific issue before Congress is whether new legislative
authorities are needed to address issues of non-native species
and their increasing economic and ecological impacts. This report
highlights the choice between single species approaches and pathway
approaches for prevention, and between prevention vs. control.
It describes existing federal laws and federal agency roles, and
outlines effects, costs, and issues surrounding 31 selected harmful
For the first few centuries after the arrival of Europeans in North America, plants and animals of many species were sent between the two land masses. The transfer of non-natives consisted not only of intentional westbound pigs and eastbound tomatoes, but also westbound dandelions and eastbound gray squirrels. And for those centuries the unwelcome and often uninvited fraction of the non-natives were ignored, if they were noticed at all. National focus on non-native species arose only with the arrival of a few species, primarily harming agriculture, the leading industry of the time. A few newly-arrived non-natives, and new estimates of adverse economic impacts exceeding $100 billion annually, have sharpened that focus.
Very broadly, the unanswered question regarding non-native species is whose responsibility is it to ensure the economic and ecological integrity of the nation in response to the actual or potential benefits or threats of non-native species? As this report shows, the current answers are far from simple, may be "no one," and depend on whether the introduction is deliberate or accidental, whether it affects agriculture, whether it arrives by one pathway or another, and whether the threat is from a pest whose harmful potential is already known. And if the harmful non-native species is already established in one area of the country, still other answers are likely.
The specific issue before Congress is whether new legislative authorities are needed to address issues of non-native species, and their increasing economic and ecological impacts. if such authorities are necessary, Congress will have to balance the needs of domestic and international trade, tourism, industries dependent on bringing non-natives in, those dependent on keeping them out, and finally, the variety of natural resources which have little direct economic value and yet affect the lives of the entire nation. if there is new legislation, should it address problems on a species by species basis, or should it try to regulate pathways of entry? Should it focus on prevention of entry or on post hoc control and intra-state quarantine? These are a few of the issues that could be debated.
In the century or so of congressional responses to harmful, non-native species, the usual approach has been an ad hoc attack on the particular problem, from impure seed stocks, to brown tree snakes on Guam. A few attempts have been made to address specific pathways (c.g., contaminated ballast water), but no current law addresses the general concern over non-native species and the variety of paths by which they enter this country. A recent Executive Order takes a step in bringing together some of the current authorities and resources to address a problem that has expanded with both increasing world trade and travel and decreasing transit time for humans and cargo. Bills have been introduced on this subject in the 105th and 106th Congresses.
This report highlights the choice between single species approaches and pathway approaches for prevention, and the role of prevention vs. control. It describes existing federal laws and federal agency roles, and outlines effects, costs, and issues surrounding 31 selected harm full non-native species.
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|Bird virus kills Toronto man after visit to N.Y.
COMTEX News Wire
by Tom Arnold
TORONTO, Sep 29, 1999 (The Canadian Press via COMTEX) -- An elderly
Canadian man has died after contracting a rare bird-borne virus in New
York City -- a disease largely unheard of in the Western Hemisphere.
The virus, known as the West Nile fever because of its roots in Africa,
has already killed at least four other people and infected dozens more.
It's transmitted to humans from mosquitoes that have bitten infected
birds, possibly crows. No vaccine exists for the virus and treatment is
Aerial spraying of entire neighbourhoods of New York City, including
Manhattan and Central Park, has been carried out in an attempt to
eradicate the mosquitoes.
As well as the recorded deaths, dozens of other people have become ill
after being bitten by the mosquitoes. All of those who died were
The 75-year-old Canadian man, whose name has not been released, was in
a coma in an intensive-care unit of Etobicoke General Hospital when he
died last Saturday.
He had returned to Canada from his week-long annual vacation to Queens,
N.Y., in early September.
Among the symptoms he experienced were fever, stiff muscles and
Blood samples from the victim are currently being tested in Winnipeg.
This is believed to be one of the first cases of West Nile virus ever
diagnosed in Canada.
American public health officials are investigating whether migrating
crows are spreading the virus beyond New York City.
Experts suspect the virus may exist in many parts of the region because
scores of dead crows have been turning up from Connecticut to Suffolk
County on Long Island.
``I have never seen crows dying in this kind of pattern in 30 years of
studying them,'' said Ward Stone, the wildlife pathologist for the New
York state Department of Environmental Conservation.
One bird from Westport, Conn., has tested positive for the illness, as
has one from Scarsdale, N.Y., officials say.
Last Friday, health officials confirmed that several other species of
birds in the Bronx Zoo and its surrounding area were infected with the
West Nile strain of the virus.
Some scientists are concerned that birds carrying the virus will take
it with them as they migrate south for the winter.
``I think this is something we need to be very concerned about,'' said
Duane Gubler, of the U.S. Centre for Disease Control and Prevention.
Dr. Harvey Artsob, head of zoonotic diseases for Health Canada, said it
is unlikely anyone in Canada could contract the virus from a mosquito.
``It is near the end of the mosquito season and the weather is turning
colder,'' he said. ``So at this late date we don't think there is going
to be any outbreak here in Canada.''
In addition to the five deaths, there are 37 other confirmed cases of
the virus in the region: 25 in New York City, eight in Westchester
County and four in Nassau County on Long Island.
The West Nile virus was first identified in 1937 in Uganda. West Nile
encephalitis has been reported in Africa, Europe and Asia.
Dr. Ned Hayes, an epidemiologist at the Centre for Disease Control and
Prevention, said the virus probably entered the U.S. in infected birds.
Copyright (c) 1999 The Canadian Press (CP), All rights reserved.
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