|
While roaming domestic cats also hunt birds
and small mammals, their feral cousins--since
they are beyond the control of human owners--take
the brunt of the blame for the decimation
of threatened species such as Least Terns,
Piping Plovers and Loggerhead Shrikes.
Cat advocates, however, say the real problem
is not feline but human. “Cats are
not the primary culprit in dwindling bird
populations,” says Becky Robinson,
co-founder of the Washington, DC-based Alley
Cat Allies (ACA). “The Worldwatch
Institute and other environmental research
groups verify that the decline in bird and
other wildlife populations is directly linked
to the loss of natural habitat,” she
says. “Urban sprawl, deforestation,
shopping malls, roads and golf courses,
and increases in pesticide use and pollution
are to blame. We need to put constraints
on our own behavior, not the normal processes
of nature.”
ACA cites a number of scientific studies
on feral cat diets which indicate that their
impacts on bird populations are negligible.
These studies conclude that cats are rodent
specialists. Birds comprise only a small
portion of their diets, and cats can prey
on birds on large land masses without destroying
their populations. Cats are opportunistic
feeders, and live mainly by scavenging and
on handouts from humans.
Feral cats are also blamed for transmitting
new diseases to wild animals, and this is
probably a legitimate charge. Cats have
spread feline leukemia to mountain lions
and may have recently infected the endangered
Florida Panther with feline panleukopenia
(feline distemper) as well as an immune
deficiency disease. Some cats also carry
diseases that can transmit to humans, including
toxoplasmosis and rabies.
Despite these issues, ACA endorses sterilization
and long-term management of feral cat colonies,
as opposed to removal and extermination
programs which they deem ineffective, costly
to taxpayers and wasteful of scarce animal
protection resources.
Regardless of one’s personal beliefs
about feral cats, individuals can play an
important role in keeping cats off the “most-wanted”
list. Most veterinarians recommend neutering
pet cats, and keeping them well fed and
indoors as much as possible to limit unwanted
reproduction, predation and the spread of
disease.
Perhaps most important, people shouldn't
release unwanted cats into the wild. According
to the Colorado-based Cat Care Society,
this practice enlarges feral cat populations
and is inhumane. Cats suffer in unfamiliar
settings, even if they are good hunters.
Contact local animal adoption organizations
and agencies for help if you need to give
up a pet cat.
CONTACTS:
Alley Cat Allies, www.alleycat.org
Cat Care Society, www.catcaresociety.org
---------------------------------------------------------------------------------------------------
Dear EarthTalk:
I've been told that automobile air conditioners
are bad for the
environment. Exactly why and what part of
the air conditioner is bad?
-
Susan Vogel, Somerville, NJ
The harmful effects of automobile air conditioners
can be directly attributed to leaking of
CFC R-12, one of a number of cooling ingredients
patented by DuPont and popularly known as
Freon. In December 1995, the U.S. banned
the manufacture of this ozone-depleting
chlorofluorocarbon (CFC) in order to adhere
to standards set by the Montreal Protocol,
an international treaty phasing out the
production of such chemicals. But existing
stockpiles of the gas--and pre-1994 autos
that still use it--could keep its toxic
legacy around for years.
The cooling ingredient HFC134A, also known
as tetrafluoroethane, has since replaced
CFC R-12 as the main cooling ingredient
in car air conditioners. But while HFC134A
does not contribute to ozone depletion and
is a more eco-friendly choice than R-12,
it is a gas that contributes to global warming.
In fact, because of this, the European Union
has slated a phase-out of HFC134A to begin
in 2011 and be completed by 2017, despite
the fact that alternatives are still only
in experimental phases of development.
Owners of pre-1994 automobiles can spend
a few hundred dollars to modify their air
conditioners to use HFC134A, though the
Environmental Protection Agency (EPA) cautions
that not all systems designed for R-12 work
as well using HFC134A and recommends such
conversions only on cars made after 1980.
When air conditioners in cars that use CFC
R-12 are being refilled or repaired, federal
regulations require that the service shops
recycle the refrigerant instead of releasing
it into the air. Regulations also require
that the refrigerant be removed from vehicles
that are scrapped or have been abandoned.
The refrigerant is then filtered so that
it can be reused.
If the refrigerant in your vehicle’s
air conditioning system needs to be replenished,
always have a professional do it. You can
damage your system if you improperly change
it yourself, and only certified mechanics
can legally purchase refill cans of CFC
R-12. Additionally, if your air conditioning
system is leaking refrigerant, have it repaired--don't
just refill it. This will both protect the
environment and save you money in the long
run.
There are other environmental considerations
with auto air-conditioners, such as energy
use. In an attempt to reduce the amount
of energy car air conditioners use, Toyota
has created a lightweight compressor--the
heart of the air-conditioner--that consumes
60 percent less fuel.
Of course, the most environmentally sound
and cheapest way to cool your car is to
open your windows and let in the fresh air.
According to the National Safety Council’s
Safety and Health Policy Center, driving
without using the car’s air conditioning
increases fuel efficiency by about 2.5 miles
per gallon.
|
