Endangered Species by: Tony Duke
Spider plants are popular house plants with long spidery stems and long
spidery leaves. However, it's an endangered species in my house and
there was a time when I would have felt little remorse if the species
became extinct. But recently my friends have been keeping them in greater
numbers because they were found to reduce formaldehyde gas within the
home.
So spider plants finally have a "use" and people are more interested
in keeping them alive. Unfortunately the plant's namesake, the real
spiders, aren't widely recognized as having a "use" and no doubt there
are many people around who could care less if spiders disappeared forever.
But as a biologist I know spiders play an important role in the web
of nature. Despite their appearance or their usefulness to mankind it
is extremely important to maintain all the parts of the web. because,
like the framework of a house, you can take away one stud from a wall
with little noticeable effect, but take away a few more studs and part
of the house collapses. Eventually, you're without a home.
Within Nova Scotia there are countless animals in nature's web but historically
only the ones "useful" to hunters have been protected by laws. today,
hunting is regulated to the point that no animal is endangered due to
hunting or trapping. In fact, these "useful" animals are now some of
the most common we have.
Most of our wildlife species are doing extremely well. Mild winters
and extensive forest cutting have contributed to the highest deer population
the province has ever seen. There are more bald eagles nesting here
than in most of north-east North America because of the abundance of
good feeding areas and good nesting sites. Cormorant populations are
high because of the good food and nesting sites they find here. Nova
Scotia has good habitat for all of them.
Despite these pluses we have some animals with low populations that
we should still be concerned about. The Committee on the Status of endangered
Wildlife in Canada (COSEWIC) lists two animals that live and breed here
as endangered, the Atlantic or Acadian whitefish which is found only
in Nova Scotia and the piping plover which frequents our beaches in
summer. Endangered means it is threatened with immediate extinction
or extirpation throughout all or significant portions of its range,
owing to the actions of man.
The Atlantic whitefish is the most rare, found nowhere else in the world
than Millipsigate Lake and the headwaters of the Petite Riviere and
Yarmouth Harbour. In the past, its numbers have been greatly reduced
by hydro-electric dams and heavy fishing pressure. today, although protected
by law, the Atlantic whitefish is still in danger from accidental catches
and acid rain. In addition to legal protection, there are plans to transfer
the fish to other watersheds and raise fish in hatcheries to reduce
the chances of its becoming extinct.
To protect the piping plover, Lands and Forests and the Canadian Wildlife
Service erected signs on the beaches where it nests to discourage public
use during the birds' breeding season. However, this has met with only
moderate success and in some cases, has attracted people to see this
rare bird. The present low population is generally attributed to nest
disturbance but may also be a result of the few naturally occurring
nesting sites - which means the population may always have been small.
This plover is rare in all its range which extends along the Atlantic
shore of North America and over the prairies of central Canada so there
are many jurisdictions that share in protecting its habitat.
Also listed as endangered is the eastern cougar, a small reddish cousin
of the more common western cougar. None have ever been shot or trapped
within the province. But every year, a few unconfirmed sightings are
report in Nova Scotia and New Brunswick (21 in 1985), so the Department
continues to list it as protected during the hunting and trapping season.
Fortunately for the endangered eastern peregrine falcon, which was exterminated
from eastern North America by pesticide poisoning and to a lesser degree
by habitat loss and shooting, there is a captive breeding program being
carried out by the Canadian Wildlife Service. Sixty-one birds hatched
in incubators in Alberta have been released around the Bay of Fundy
since 1982 and Nova Scotians get an occasional glimpse of them near
the Bay. We hope this small nucleus of birds will return to breed and
develop into a self-sustaining population
The right whale gets its name from the first whale hunters who felt
it was the "right" whale to hunt because its slow speed and oil-rich
body floated when it was dead. After centuries of exploitation off our
shores, it is listed as endangered and since 1972 there have been no
Canadian whale hunts. While this has protected the whales, it has removed
the best method scientists had to measure whale numbers. It takes a
lot of expensive flying and shipboard time to find and count these animals,
and, apart from oil companies and some United States investigators,
few sources of money are available for whale censuses.
The World Wildlife Fund Canada is supporting a research project in the
southern Bay of Fundy this fall and winter to investigate the right
whale's feeding grounds located 15 kilometres offshore. These areas
of dense zooplankton are critical parts of the whales' habitat where
conflicts with marine traffic take their toll on feeding whales.
This past summer, COSEWIC listed the roseate tern as "threatened", which
is the next step up from endangered. There are 3100 breeding pairs in
North America and up to 125 pairs nest on Nova Scotia's south shore
beaches and Cape Breton. Ornithologist Robie Tufts reported historical
tern nesting colonies had been taken over by increasing populations
of the more aggressive herring gulls. Roseate terns are found along
the seaboards on both sides of the Atlantic. Unfortunately on the birds
winter range in South America, hunters still collect the birds for their
feathers.
Apart from these animals officially listed by COSEWIC, there are some
small populations of animals found in Nova Scotia that are termed "remnant"
populations. They are isolated from the major populations by geographical
barriers at the northern or southern fringes of their range. They continue
to live here because there are isolated pockets of habitat that are
similar to that found where the major population is found.
A well known example is the Blanding's turtle that lives within the
boundaries of Kejimkujik National Park. The same animal can be found
in large numbers in southern Ontario west to eastern Nebraska, and in
scattered locations farther south on the east coast. So it's not in
danger of becoming extinct; but our population may be threatened by
fire or other habitat change or disturbance by people in the Park.
These remnant populations are a scientific curiosity and may one day
give researchers insight into animal adaptation to colder or hotter
climates. They may also be part of the ongoing process of evolution
where survival of the fittest may eventually lead to a new species.
They may also turn out to have a"use" for Nova Scotia's or, in case
of a catastrophe, be a seed stock to reintroduce animals if the major
population is wiped out (like our peregrine falcon or the bald eagles
in the southern United States).
Other remnants include the lynx, rare on the highlands of Cape Breton
but abundant in northern Canada; the ribbon snake which occurs only
in Queens and Lunenburg counties but it is also found through south
central North America; the yellow lamp mussel who only Canadian location
is the Sydney River, but is also found from Maine to Georgia; and the
Gaspe shrew (which is the only North American mammal who range lies
entirely within the borders of Canada, found in Victoria County but
more extensively in the Gaspe and northern New Brunswick.
We may yet find more remnant or endangered populations of small mammals,
reptiles and amphibians but it will take a long time since there are
only a few investigators in the field looking for them. Biologists from
the Nova Scotia Museum only trapped the first specimen of long-tailed
shrew from Nova Scotia in 1984. It takes many hours of looking to find
these animals that are not so "useful" to us as the white-tailed deer.
Whether rare, threatened or endangered, the best policy for animal protection
is protecting the habit. a 1985 policy statement by the government of
Nova Scotia set up a committee to examine wildlife habitats and gave
authority to protect vital habitats. The new forestry legislation introduced
in 1986 dictates that wildlife habitats will be considered in forest
management plans on Crown lands and guidelines will be drawn up for
private lands.
However, accidents will happen and animals like the whitefish may be
lost if their small habitat is damaged. but if extensive habitat is
opened up to the whitefish, the population will grow by itself and overcome
the risks. habitats will change as a forest matures or is harvested
but if representative samples of different ages of forest are designed
into the forest management plan, the Gaspe shrew will always find the
mature hardwood forest on steep talus slopes it needs.
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