Impact of an introduced species to the Abaco's ecology |
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Abaco Fire Ants Part 2 of a 2 part series - to read part 1, Please Click HERE In my last article I talked about a species that has recently been introduced to Abaco - the common raccoon (Procyon lotor). Unfortunately, raccoons are not the only unwanted newcomers to our island. All over the planet, wherever humans go, we have introduced new species either accidentally or by design. Some of these species fit into the existing ecosystem with little or no fuss and others may have catastrophic effects. Here in the Bahamas we have very little native flora and fauna that can truly be devastated by exotic species - we are not the Galapagos - but we have managed to make life a little harder for ourselves along the way. Does anyone remember when fire ants arrived? As a child growing up between Nassau and Hope Town, I encountered many many different types of stinging insects and stood in more ant piles than I can remember, but never fire ants. Fire ants are listed in the Guinness Book of World Records as the world's most dangerous ant. They are native to South America and were introduced to the Unites States in the 1930s. From there they hitched a ride to the Bahamas sometime in the 1980s, most likely in the root balls of imported plants and trees. Fire ants are not like the native black and red ants I grew up with - they are much more aggressive and build large porous mounds that crumble under a touch. A fire ant bite is no laughing matter - the poison festers for days under the skin producing a fierce itch and eventually a pimple-like pustule. A single bite is bad enough, pity the poor soul who stands in a whole nest! It is ironic that in a country already host to scorpions, doctor flies, billions upon billions of mosquitoes, black widow spiders, wasps, sand flies, six-inch-long centipedes and several perfectly competent species of ant (not to mention sea lice and jellyfish), we have introduced yet another type of stinging critter to plague ourselves with. What other species are arriving? I have personally seen how animals are introduced unknowingly. Two years ago, while arranging to have my car sent over to Abaco from the Port of Palm Beach, I rescued a toad. The toad, a common Bufo americanus, was sitting in a coil of hose by the warehouse door, in the hot sun, looking very sorry for himself. I put him in my hat and later that day released him near the Kennedy compound on Palm Beach Island where I figured he would have a chance of finding some decorative fountains to live beside and perhaps another toad or two to keep him company. He had ridden to the port in a box of Romaine lettuce, and if he had not jumped out of the box would have been imported to Abaco along with all the other foodstuffs that week on the Duke of Topsail. In fact, we may already have a population of American toads, although I have not seen any in the wild. We do, however, have another introduced species of toad in residence, and one that has been reviled the world over, Bufo marinus, the giant cane toad. Cane toads are native to Central and South America; they are huge, warty, poisonous things that can grow up to nine inches in diameter - about the size of a dinner plate. During the first half of the 20th Century, these toads were introduced worldwide in areas where sugarcane was grown to control beetles that were ruining the crops. The problem is that nobody told the toads that they were supposed to eat only the beetles. Once they were released, they did as they pleased. In Australia cane toads are a true plague - inedible to all the local predators. The toads are multiplying like crazy, eating everything smaller than they are and advancing something like 17 kilometers a year! Luckily for us, the situation here is nowhere near so dire. Cane toads have been here for several decades now and have become quiet and retiring co-residents of Abaco - in fact, I hardly ever hear of their being sighted and I admit that I have never seen one here. We are lucky - in Florida during the 1980s the toads became so numerous that they regularly turned up in suburban back yards, where they sometimes poisoned curious cats and dogs. It may be that we have been spared this plague of toads because our environment lacks enough standing fresh water for them to spawn unchecked or it may be something else. In any case we should be grateful. The problem of introduced species seems to be insolvable. Certain places like California and Hawaii have instituted huge programs to prevent the importation of foreign pests. Hawaii, in particular, is engaged in an ongoing war with a type of tree snake that threatens to eat all its native species of birds as has happened on the island of Guam. Abaco, however, does not have the money to spare for this kind of initiative, and, in any case, I am not convinced that such stringent measures would be appropriate. And so the flood of exotic species will continue. Humanity is the great equalizer - our global network of shipping gives any opportunistic species multiple occasions to extend their habitat. Since I have been on Abaco, I have already seen in the wild a type of highly predatory centipede that used to be native only to East Asia. You know the line from the song, Day-O - "A beautiful bunch of ripe banana/hide de deadly black tarantula!" We don't have tarantulas here yet . . . do we? |
