News : General News
Introduced Species are Our New Residents
September 24, 2009 -- Humans have been transporting species around the world, intentionally and unintentionally, for centuries. Many of the species we think of as a natural part of our landscape are, in fact, non-native. For example, the honeybee, which nearly a third of US states have named as their state insect, was introduced into North America from Europe in the 1600s.
Naturalists have long been aware of this bio-globalisation, but widespread research on introduced species did not begin until the early 1980s. In those days, the message from invasion biologists was clear and simple: introduced species were bad news. They were referred to as invaders, aliens, exotics or even "biological pollution". A common refrain was that invasive species were one of the greatest extinction threats for native species, second only to habitat destruction.
Make no mistake, some introduced species have caused great harm. For example, the brown tree snake, introduced into Guam in the mid-20th century, caused the extinction of most of the island's native birds. Many other island and lake species have been driven extinct by introduced predators. The global cost of damage by non-native species to farming, timber, fisheries and waterways is estimated at well over $100 billion annually. Many of the human diseases of greatest concern are viruses that have been transported to new regions, such as SARS, West Nile virus, Ebola, H1N1 flu and HIV.
However, you may be surprised to learn that only a few per cent of introduced species are harmful. Read the full story to get the details.
"Most are relatively benign; some, such as the honeybee, can even have beneficial effects. Despite this, many people cling to the idea that non-native species are uniformly undesirable."
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