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Illegal Aliens african dartfrogs, parrots, wallabies, piranhas, alligators, iguanas, wolf, etc. Tourists visiting Hawaii have also introduced other alien species. Each of these introductions threatens the ecological niche of native species. Prevention: The Endangered Species Act of 1973 gave the states primary authority for managing endangered species programs and it has become the responsibility of the Hawaiian government to inspect the cargo of tourists. The Secretary of Agriculture is required to operate a program to protect Hawaii from the introduction of alien species. It is an inportant part of the program to inform the public (locals and visitors) about the prohibitions against shipping plants, plant pests and injurious animals and the consequences of smuggling attempts. There are laws against importing these unwanted animals to Hawaii: criminal statutes make it a crime and fines serve as a deterrent to tourists who are tempted to bring them here. Dogs have been trained to sniff out foreign species of plants and animals at Hawaiian airports. An amnesty program in 1990 allowed people to turn in a variety of illegal species without legal repercussions. Among the species that were turned in were african clawed frogs, coral snakes, and even a hybrid wolf. Caimans and alligators have also been temporary residents on O'ahu. In 1983 two caimans, a South American cousin of alligator, were found in Nu'uanu Reservoir. In 1991 the bodies of two alligators were found in Kailua. The first was discovered in Maunawili Stream in April and measured six feet. The other, over five feet in length, was found along the Kapa'a Quarry Road four months later. In 1916 three wallabies were purchased for a private zoo at the 'Alewa Heights home of a Mr. Trent. Neighborhood dogs attacked the new arrivals and the youngest wallaby was killed. The remaining two escaped into the hills to establish a colony of wallabies that still lives in Kalihi Valley. (The wallaby once inhabited the area from Nu'uanu to Halawa Valley. People and dogs restricted their range to Kalihi Valley where steep cliffs and dry caves provide protection and shelter. Impact Since Its Arrival: wallabies inhabit a tiny area of O'ahu and have not yet affected native animals and plants.) The Brown Tree Snake Threat 1.) Accidental invasion: Scientists are very concerned that the 10-12 foot brown tree snake, a native of New Guinea - which has caused devestating ecological damage in Guam after arriving there on board of a cargo plane - will establish a population in Hawaii and destroy the remaining honeycreepers. Not having evolved with a nighttime arboreal (tree climbing ) predator, the native birds would have no behavioral or physical defenses against them. Brown tree snakes are said to have arrived in Hawaii by slithering into wheel wells of jets and dropping out when the planes land. Between April 1981 and December 1994 seven brown tree snakes have been found in Hawai`i, two at the Honolulu International Airport, three at Hickam Air Force Base, one at Barber's Point Naval Air Station, and one at Schofield Barracks. Threat 2.) Deliberate introduction: Snakes are a favorite pet to smuggle into the state. They are increasingly being found in the wild as escaped pets or animals released by their owners. 1992 was a record year for snake finds; 38 snakes (dead and alive) were found! Between July1994 and February 1998 sixty-three snakes have been confiscated, turned in to the state or caught in the wild in Hawaii. Only one of them was a brown tree snake, caught in a Schofield Barracks warehouse in December 1994. The rest were species commonly kept as pets on the mainland : they included 11 pythons, 11 boas, 4 corn snakes, 2 vipers and several garter snakes among others. Prevention Efforts With a constant stream of flights arriving in Hawai`i from Guam, state, federal and private agencies teamed up and have joined forces to try to prevent the establishment of the brown tree snake in Hawaii. Most U.S. international airports use special units of trained detector dogs to help agricultural inspectors and sniff out snakes and other foreign animal and plant pests. Since 1986 ten brown tree snakes have been intercepted at Honolulu Airport by the specially trained Beagles Brigade. The maximum penalty for bringing a snake into Hawaii has recently been increased to $200,000 and three years jail time!. Roughly one third of the snakes caught or received by the Plant Quarantine Station between July 1994 and February 1998 were turned in under an amnesty program that allows people to surrender illegal animals and plants without penalty. In its arsenal against a snake invasion, the state also has another method employed by the DLNR in an effort to catch snakes. Traps are baited with live animals, usually mice. In response to the maui snake sighting, for example, the DLNR set 60 such traps. Most snake experts will admit this is not a terribly effective means of catching snakes. It is done not because of high expectations of success, but rather to make certain all possible avenues are exhausted. Nor is the ineffectiveness of traps difficult to explain. As prey densities (that is, rat populations) are so high in cane fields, getting a snake to enter a baited trap would almost be a matter of dumb luck. Traps are somewhat more effective in Guam. There, brown tree snakes have wiped out most food sources and are looking for anything to eat. In the wild, most of the birds are gone so they basically feed on lizards and whatever else they can find, that's why they go in the trap. But in Hawai`ithere are still a lot of birds. The snake is not likely to enter a trap when it can catch its own bird on the tree. Traps are also expensive to maintain. Each trap needs live bait that must be fed and changed on a regular basis. Other possibilities include physical barriers, fumigants to treat cargo containers, and biological control. All are still in the early research stages, and almost all of these are focused only on the brown tree snake. Teamwork between agencies to respond to snake sightings and assist in search efforts: Response time is a critical factor.If a snake is not caught within minutes of its sighting, it is most likely it will not be caught at all. It can take as little as half an hour to mobilize searchers but if it looks as though it will take longer than two hours for Department of Agriculture personnel to arrive at the site of the spotting, other agencies are called in to help. These might include the state Department of Land and Natural Resources, military personnel, or volunteers trained by the DLNR to hunt for snakes. (The Fish and Wildlife Service cannot use funds to assist in searches unless the snake is suspected to be a brown tree snake.) The Brown Tree Snake Control Committee was formed in May 1993 to address the snake problem in Hawai`i, as well as Guam and the Mariana Islands. Another group established to foster cooperation in the fight against invasive alien species is CGAPS, or the Coordinating Group on Alien Pest Species. CGAPS members include the state Departments of Agriculture, Health, Land and Natural Resources, and Transportation; and an array of federal and private organizations, most prominent of which is The Nature Conservancy of Hawaii, instrumental in bringing the coalition together. CGAPS has produced "The Silent Invasion", an educational brochure that describes the threats alien species pose to Hawai`i and includes top-ten list of Hawaii's "most unwanted" pests. The brown tree snake is listed as number one. No other snakes appear on the list. This booklet describes another example of the state's inability to prevent snake smuggling: first-class mail, based on the Fourth Amendment, is protected from inspection in spite of evidence that the mail is a common pathway for live animals, insects, and weed seeds. Without a court order, authorities cannot inspect a package suspected of carrying a restricted animal, nor could they record the name and address of the intended recipient. It is a violation of postal laws to mail dangerous animals, including poisonous snakes but if the smuggler doesn't elect to announce his contraband cargo to the Postal Service, that law is hard to enforce. What else can be done? There's a need for public education. More people need to know that Hawaii is, or at least is supposed to be, snake free. There certainly needs to be education at judicial level. Even when smugglers of snakes are caught, there is no assurance that penalties commensurate with the crime will be imposed. "Judges need to impose a satisfactory penalty that matches the importance of the crime. Possessing a snake may not be as problematic as killing someone, but if a snake becomes established, it has far-reaching effects." As much attention as the brown tree snake has received, programs to control its spread are generally acknowledged to lack sufficient resources. Still, they have the support of policies, control plans, and federal and state funds. No similar system exists for the other snakes that have been or could be found in Hawaii, many of which pose a threat that could approach that of the brown tree snake. Guam's invasion by the brown tree snake (Boiga irregularis) is one of the most notorious examples of what can occur when a snake colonizes an island that lacks natural defenses. The brown tree snake has been held responsible are responsible for killing 9 of Guam's 11 native forest bird species, shore and sea birds, an insect-eating bat, and several lizard species. Declines in the populations of introduced birds, mammals, geckos and skinks have also been attributed to snake predation. Prey species on islands seem to be especially vulnerable lacking coevolutionary experience with nocturnal arboreal snake predators. Brown tree snakes crawling on power lines have caused hundreds of power outages - about one every four days on average. The snakes, which are slightly venomous, have also preyed on poultry, pets, and have bitten more than 200 residents. Native to Indonesia, New Guinea, the Solomon Islands, and Australia, the brown tree snake was accidentally introduced to Guam shortly after World War II, probably as a stowaway on a cargo ship. In less than 20 years!, the snake established itself throughout Guam, reaching densities as high as 40 snakes per acre during the 1970s and 1980s. Wild Pigs and their effect on our bird population Today, the most destructive force in native forests - besides land development - is feral pigs. Although pigs were brought to the Hawaiian Islands by Polynesians as early as the fourth century A.D., the current severe environmental damage inflicted by pigs apparently began much more recently and seems to have resulted entirely from release of domestic, non-Polynesian genotypes. (Polynesian pigs were much smaller, more docile, and less prone to taking up a feral existence than those introduced at later times.) Today's wild pigs probably descended from runaway domestic breeds in lowland areas. Perhaps aided by a seasonally abundant and expanding carbohydrate source-the invading nonindigenous strawberry guava-and by an enhanced protein source from abundant nonindigenous earthworms, truly feral pig populations developed and spread into adjacent pristine forests. European domestic pigs were among the earliest introduced species to arrive in Hawai`i. Without predators or herbivore competitors, these animals adapted well to life in the wet forest and rapidly established large feral populations. Their populations multiply unchecked, (a single pair and their offspring theoretically can produce 15,000 pigs in five years!). Feral pigs have endangered many of the native plant species by overgrazing in the rain forest. They churn up the forest floor in search of earthworms and fleshy plant roots and destroy vulnerable native plants such as mints and orchids. The starchy core of native tree ferns is also among the pigs' favorite foods. The pigs gnaw at the trees' bark and devour valuable nutrients from the forest floor. Opportunistic plant species, often nonindigenous, occupy the habitats remaining after feral pigs have eliminated native species. Seeds of nonindigenous plants are carried on pigs' coats or in their digestive tracts, and they thrive upon germination on the forest floor where pigs have exposed mineral soil. Once these aggressive plant invaders have obtained a new foothold in the forest, they spread aided by pigs and nonindigenous birds. Measures to control pigs In the early 1900's, the damage caused by feral European pigs in native rain forests was recognized; the Hawaii Territorial Board of Agriculture and Forestry subsequently started a feral pig eradication project that lasted until 1958 and removed 170,000 pigs from forests statewide. The Hawaiian government has encouraged hunters to stalk the feral pigs. All legally hunted game animals in Hawaii are introduced species. Park crews build goat and pig-proof fences around portions of parks that possess special ecological values. They eliminate pigs and offensive alien plants within these areas and the forest begins to heal with the return of native plants and animals. The fencing costs more than $40 thousand dollars per mile. The costs can be much higher in remote, rugged terrain. Haleakala National Park has spent about $5 million dollars to protect the crater area. Once you get the fence installed, the hard work begins. You've got to get rid of all the animals inside the fence. The first ones are pretty easy but it gets much harder as you progress. You've got to get into very inaccessible areas. About 10,000 acres have already been enclosed with pig-free fencing and are showing significant signs of recovery. When you eliminate these feral animals, it doesn't make you popular. Some people would rather have the alien animals than the native plants. (The group that has come under the most criticism for its alien animal control program is The Nature Conservancy who used snares to trap pigs on Molokai, so animal-rights groups have accused the conservancy of being in-humane.) An ecosystem is a balanced interaction of plants, animals and the environment in which they live. The balance is easily upset by "alien" interference. Look at how the alien pig is part of a chain of events that leads to disaster for native birds: Myrica faya, an alien plant, begins to grow in a native forest. Earthworms are attracted to the roots of the plant. Pigs turn up the ground in search for the tasty earthworms. The disturbed ground collects rainwater and puddles form. The puddles provide a comfortable wallow for the pigs. Culex quinquefasciatus, an alien mosquito, is attracted to the standing water in the puddles and wallows. The mosquitoes lay their eggs there and the population grows. Plasmodium relictum is an alien parasite found in many birds, though it has very little affect on introduced birds. Mosquitoes become parasite carriers once they bite an infected bird. They then spread the parasite and alien viruses to other birds in the same manner. Native honeycreepers have no resistance to the disease. They develop avian malaria or bird pox, which shortens their lives and depletes their populations.

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