Tuesday, May 06, 2008

Invasion Beyond the Coast: Threats to Biodiversity

Last week, we introduced a growing problem off the shores of the eastern United States and organizations looking to solve this problem. In this installment of Invasion Beyond the Coast, we will look at what makes a species invasive and at the species assaulting our coastline.

"Alien species means," according to The National Invasive Species Information Center (NISIC), "with respect to a particular ecosystem, any species, including its seeds, eggs, spores, or other biological material capable of propagating that species, that is not native to that ecosystem.”

Because these non-native species often have no competition or predators, their population grows unchecked. They consume food and territory from native species and may also carry diseases of which the native population has no immunity.

This is when the NISIC classifies them as an "invasive species," which means “an alien species whose introduction does or is likely to cause economic or environmental harm or harm to human health.”

You might ask yourself how a species can cause economic harm.

Imagine if a species of crab was introduced into the waters off the Atlantic coast. It competes with lobsters for food and territory so much so, that the lobster industry goes under.

Some people might say there is no way for an invasive species to affect an ecosystem like this. But take the Caulerpa taxifolia, for example. This marine algae has decimated many parts of the Mediterranean Sea. Recently, groups like the Southern California Caulerpa Action Team (SCCAT) have taken up the cause to make sure this weed doesn't get a foothold in California waters.

This project has cost $8.3 million to date.

Today, Atlantic natives face threats from fish around the world. These fish include: Emperor Angel (Pomacanthus imperator), 5 other species of Angelfish (Pomacanthus spp.), Orbicular Batfish (Platax orbicularis), Lionfish (Pterois volitans), 3 varieties of Sailfin Tangs (Zebrasoma spp.), Raccoon Butterflyfish (Chaetodon lunula), yellow tang (Zebrasoma flavescens), Orangespine Unicornfish (Naso lituratus), and Morrish Idol (Zanclus cornutus).

These animals are native to Indo-West Pacific or Red Sea, but are in the Atlantic most often due to inexperienced aquarists who can no longer care for their animals. Although these animals are beautiful and a treat to see in the wild, this is not where they belong.

For information on how you can help, visit REEF.org.

Be sure to catch the final installment of Invasive Beyond the Coast, where we will discuss the how the average aquarist can make an impact on biodiversity.