 |
| Image: national geographic |
Most humans hunt to get selected types of animals. This causes
certain types of animals to become rare because they are being killed
everyday and are failing to reproduce.
2. DEFORESTATION
 |
| Image: BBC |
Deforestation occurs via logging
or burning, and there are four main motives that fuel the chainsaws and
stoke the fires: wood for fuel usage, lumber for construction, land
clearance for plantation or ranch development, and urban expansion.
Forests provide vital shelter and nesting structures and a bounty of
food for animals and if it is destroyed they die.
3.PESTICIDES
 |
| Image: galleryhip.com |
At least 5 billion pounds of
pesticides are manufactured each year; 20% is used within the United
States or Western Europe. Per capita, the most frequent users of
pesticides are the monoculture farms of Central America, (such as banana
plantations) as well as the large producers of cereal grains and fruit
in Brazil, the US, and France.
Common ways in which
pesticides damage animal populations are death by exposure from a
concentrated dose, bioaccumulation (fat-soluble chemicals increase in
concentration with every step up the food chain), hormonal effects, and
fewer or weaker eggs. They can also destroy of prey organisms and damage
plants used by birds for feeding, roosting, and nesting.
4. INVASIVE OR INTRODUCED PESTS
 |
| Image: gettyimages |
People use a lot of different crops and
domesticated animals for farming, and a lot more animals and plants
(like mice, rats, cockroaches and weeds) live and thrive around us even
if we don't want them to!
As people have spread around the world, they have taken many of these species with them, either deliberately or accidentally.
But introduced species often have a very harmful effect on native species. For
example, 24 rabbits were introduced to Australia in 1859 for hunting.
Rabbits breed quickly, and, in an environment without any of their
natural predators, their numbers increased so quickly that in less than a
hundred years there were 600 million across the whole continent! The
rabbits took over the resources and habitats of native species, like the
bandicoot, which is now endangered.
5. POLLUTION
 |
| Image: framepool.com |
Pollution contaminates the natural environment with harmful substances produced by human activity.
An obvious example of pollution is an oil spill.
This happens when oil is released accidentally into the sea from a
tanker, pipeline or refinery. The spill forms a thin layer of oil,
called a slick, poisoning sea life, and damaging the fur and feathers of
seabirds and mammals.
6. POPULATION
 |
| Image: buzzle.com |
The growth of the human population is the biggest threat to natural environments today. One
hundred years ago, there were one billion people in the world. Now
there are over six billion!Quite simply, there isn't enough room for
natural environments to
coexist with all these people, and the land they need to provide them
with food and shelter.
7.OVER-HUNTING
 |
| Image: creativetravelphoto.com |
Many of the world's biggest and
most impressive animals, such as whales, elephants, rhinos and tigers,
are now all rare because they were hunted heavily in the past.
People wanted whale oil and whale meat, elephant ivory, and rhino and
tiger trophies. Although all of these animals are now protected by law
from excess hunting, illegal poaching still continues.
No comments:
Post a Comment