Introduced Species

A prime example of biotic pollution is in Australia. Being an island, Australia is home to some very unique species found no where else in the world. Also, it didn't originally have some of the common animals found in Europe or America. When Europeans colonized Australia 200 years ago, the brought over some of these animals, including rabbits and foxes to hunt, and cats to keep their fields free from rats. Unfortunately, the animals weren't contained, and their population exploded and they spread out all over the country. The current rabbit population is 500 million and they have become a major pest because they cause soil erosion, they destroy the habitat of many native species, and they cause huge commercial production losses. Cats and foxes have no natural predators in Australia, and have feasted on the defenseless native marsupials since they were introduced. Because of the abundance of food, the cats are getting much bigger, and many have been seen the size of California bobcats. Unfortunately, the native marsupials that they feed on have not fared so well; their populations continue to dwindle and disappear.
Mammals aren't the only ones that have caused havoc in Australia; Bufo Marinus, a large poisonous toad, was introduced to Australia and many other countries such as the United States, the Philippines, and the Caribbean from South America. It was thought that the toad would eat the pests that were damaging sugar cane crops in these areas. However, when it was introduced, it preferred the human environment better than the sugar cane fields, and with an abundance of garbage and pet food to feed on, the population of Bufo Marinus soon multiplied and spread all over Australia.

Year Area occupied (sq km)
1939 32,800
1944 55,800
1949 73,600
1954 138,000
1959 202,000
1964 257,000
1969 301,000
1974 584,000
(data collected from http://www.eom.umn.edu/education/calc-init/population/unbounded.html)

The toads have killed many dogs with the poison they secrete and some ponds have become uninhabitable by animals because the toads have poisoned the water.


Bufo Marinus: a BIG pest A prime example of biotic pollution is in Australia. Being an island, Australia is home to some very unique species found no where else in the world. Also, it didn't originally have some of the common animals found in Europe or America. When Europeans colonized Australia 200 years ago, the brought over some of these animals, including rabbits and foxes to hunt, and cats to keep their fields free from rats. Unfortunately, the animals weren't contained, and their population exploded and they spread out all over the country. The current rabbit population is 500 million and they have become a major pest because they cause soil erosion, they destroy the habitat of many native species, and they cause huge commercial production losses. Cats and foxes have no natural predators in Australia, and have feasted on the defenseless native marsupials since they were introduced. Because of the abundance of food, the cats are getting much bigger, and many have been seen the size of California bobcats. Unfortunately, the native marsupials that they feed on have not fared so well; their populations continue to dwindle and disappear. Mammals aren't the only ones that have caused havoc in Australia; Bufo Marinus, a large poisonous toad, was introduced to Australia and many other countries such as the United States, the Philippines, and the Caribbean from South America. It was thought that the toad would eat the pests that were damaging sugar cane crops in these areas. However, when it was introduced, it preferred the human environment better than the sugar cane fields, and with an abundance of garbage and pet food to feed on, the population of Bufo Marinus soon multiplied and spread all over Australia. Year Area occupied (sq km) 1939 32,800 1944 55,800 1949 73,600 1954 138,000 1959 202,000 1964 257,000 1969 301,000 1974 584,000 (data collected from http://www.eom.umn.edu/education/calc-init/population/unbounded.html) The toads have killed many dogs with the poison they secrete and some ponds have become uninhabitable by animals because the toads have poisoned the water.

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