Snakes in Bermuda?
Is it only a matter of time before poisonous snakes or spiders establish themselves here?
Tuesday, April 14, 2009 10:29 PM
New species of poisonous snakes and spiders will most likely establish in Bermuda unless the island does more to protect against invaders, experts warn.
A Boa Constrictor: several have been found here in recent years. *MCT photo
A few of the more unusual stowaways that have reached Bermuda - many of which could now be permanent residents if it wasn't for the vigilance of Customs and the public:
The Black Widow: This highly poisonous north American spider was recently found breeding in a Somerset home. It was probably imported amid building materials. Experts believe they destroyed the individuals before the population spread.
Raccoon: In September this year customs officers opened a crate containing an air-conditioning unit and found a live and healthy raccoon. The animal was destroyed since it was judged too costly and complicated to repatriate it to Canada.
Praying Mantis: A close relative of the cockroach, this large predatory species could potentially run amok in Bermuda. Fortunately, the Department of Environmental Protection has so far managed to identify incoming egg cases and had shipments fumigated.
Carpenter Bees: An entire population of carpenter bees was discovered within the plastic seal that enclosed a new yacht arriving on the island. The bees were fumigated and destroyed.
Saw-whet Owl: A tiny saw-whet owl went to sleep in a coniferous tree and somehow failed to wake up when the tree was cut down and imported to Bermuda as a Christmas tree. The owl was removed from the tree and cared for until it died of natural causes.
Boa Constrictor: This native of America and the Caribbean is sometimes bought to the island as a pet. Some are released when they grow to full size; others escape. A heat seeking snake that crushes its prey, the boa can be a threat to small dogs and would be a severe danger to the Cahow and other endemic species.
Research: Tim Hall
Bermuda has so far been "very fortunate" not to have breeding populations of black widow spiders, coral snakes and other potentially deadly creatures, according to Dr. David Wingate, one of the island's top environmentalists.
It follows the recent discovery of several black widows in a house in Somerset. Environmental protection officers believe they exterminated the spiders just in time, but they could easily have bred more widely and become Bermuda residents.
Dr. Wingate said: "There is a steady trickle of new things coming in. The black widow is just the latest in a long line. We don't know what lurks around the corner. So far we are just very fortunate some of these things haven't gone on to establish themselves; because once they are established you are stuck with them forever. In the future tourists may have to cope with poisonous spiders and poisonous snakes that before we could boast we were totally free of. We lose one more piece of our heritage that makes us recognizable as Bermuda. In my opinion the costs of this deadly game are so high and we are not doing enough to protect ourselves. As an oceanic island we are so, so vulnerable."
Species introduced from abroad tend to wipe out species that already exist. Dr. Wingate said the economic cost of these introductions can be "unbelievably staggering." The prime example is the introduced scale insect that destroyed most of Bermuda's cedar trees in the 1940s. Dr. Wingate said: "How much would all that cedar timber have been worth if we had been harvesting it right up to today? How much did we lose?"
Bermuda's first human settlers deliberately introduced hogs and accidentally introduced rats, both of which ravaged local wildlife. The ubiquitous kiskadee bird and the Brazilian pepper tree are two more examples of introduced species that have run wild. Today experts estimate only five per cent of the island's original fauna and flora survives.
Rogue species of snake continue to arrive in shipping containers - carried amid lumber or bricks. Spiders can creep into golf bags in U.S. cellars and go undetected though Customs. Other invasive species can arrive on plants imported for the horticultural trade. In addition, some people deliberately import or smuggle in snakes as pets, which Dr. Wingate says invariably escape. Three times in recent years Dr. Wingate has helped track down escaped boa constrictors. He said: "These snakes can grow to six, eight feet, and they can swim out to the [smaller] islands, no problem. They are heat seeking, and they could have crawled into the cahow burrows. Some people are fascinated by these snakes, but the damage they could do in the wild is staggering."
Tougher laws needed
Dr. Wingate believes Bermuda needs tougher laws and punishments for people who bring invasive species to the island. He would also like to see Bermuda demand all shipments be thoroughly fumigated. "This would of course increase costs. But what are the costs of these species becoming established in Bermuda?" Most importantly, Dr. Wingate would like to see school children taught about invasive species from an early age so that all Bermudians can do their part to help keep invaders out.
Claire Jessey, entomologist at the Department for Environmental Protection, agrees that education is the key. She said: "There are so many ways pests can get here: when you import granite slabs for your garden; in PVC piping; in shipments of bricks; in Christmas trees. We need to make people aware of the risks and of what the repercussions could be. Once the snake or animal gets established it may be here indefinitely. Educating the children is key. They have very sharp eyes: often they are first to notice there is a new creature in the garden." She also agrees with Dr. Wingate that the island has been lucky not to have resident populations of black widows and other poisonous creatures. She said the chances are "reasonably high" that such species will establish here unless the country is more vigilant.
Some isolated countries, such as New Zealand, have far tougher border controls for pests and far tougher penalties for anyone who allows an invader into the wild. Mrs. Jessey, agrees that some countries are "definitely more vigilant." She said customs officers work hard at the ports to check for signs a shipment may be infected with insects or other pests. The Department for Environmental Protection inspects every imported shipment of plants, and turns away shipments of high-risk species. Mrs. Jessey believes the country's laws are adequate, and that education is the best way to increase vigilance against invaders.