Years ago, Missouri wildlife managers decided to reduce an exploding deer population in a St. Louis suburb. But instead of culling the herd humanely, they bowed to pressure from animal lovers, and, at great expense, trapped and moved deer to a more rural area.
Follow-up research revealed that those deer died of starvation. They had grown so accustomed to eating tulips, roses, and other domesticated plants that they did not recognize wild forage.
Besides showing the folly of trying to manage wildlife by emotion instead of science, this example reveals one of the reasons that exotic species can become so prolific and troublesome in their new habitats. Native species do not see them as food, and, consequently, their populations are free to grow unchecked by predation.
Down in the Caribbean, divers are trying to do something about that by teaching sharks to eat invasive lionfish. The latter are gobbling up native species, especially reef fish.
“From a scientific point of view, we don't know how successful the project is. But, apparently, recent videos show native top predators are starting to eat lionfish without them being previously speared by divers,” says a marine biologist. (Go here to see some great photos of sharks eating lionfish.)
Meanwhile, lionfish populations have declined around Jamaica because another species is eating the invaders --- man.
Dayne Buddo, a Jamaican marine ecologist who focuses on marine invaders at the Caribbean island's University of the West Indies, attributes much of the local decrease in sightings to a growing appetite for their fillets. He says that Jamaican fishermen are now selling lionfish briskly at markets. In contrast, a few years ago island fishermen "didn't want to mess" with the exotic fish with spines that can deliver a very painful sting.
The same strategy eventually may help us control Asian carp in the nation’s rivers and impoundments. Go here to check out my post about that.