Grade 8 | Informative | Text-Dependent
You have read an article and an excerpt from a book about invasive species and their impact on the environments that they invade.
Write an essay in which you demonstrate how the article and the excerpt emphasize different aspects of the problem and explain how these ideas are connected. Use evidence from the article and the excerpt to support your explanation.
by Alan Burdick
A stewardess came down the aisle handing out slips of paper printed with orange lettering; declaration forms. I declare: No, I harbor no fresh fruits or vegetables. I have no live lobsters or claims to speak of, no flowers, foliage, rooted plants, or plant cuttings; no seeds, bulbs, soil, or sand; no bacteria, no algae, no fungi, no protozoa. No, I am not traveling with a dog or a bird or a turtle or a lizard. Oahu appeared through the porthole; Diamond Head crater to the west, the high-rises of Waikiki merging into those of Honolulu, pearls of concrete strung along a white sand beach. The plane banked over sugarcane ﬁelds, over Pearl Harbor. With the continents of Asia and North America more than two thousand miles away, Hawaii is the most isolated major landmass on Earth, the pilot announced. His voice rang over the loud-speaker: We are farther from anywhere than anywhere.
I had come, ostensibly, to see about a snake. That is an uncommon pastime in Hawaii, for the simple reason that, as far as anyone can yet determine, there are few snakes to be found. Once or twice a year someone’s pet boa constrictor or Burmese python escapes and reappears in Waikiki or Waimea garage, prompting a call to the animal squad at the Hawaii Department of Agriculture. The only snake know to be established in the state in the Braminy blind snake, a sightless, wriggling creature closer in size and spirit to a worm.
The snake I sought was, like me, a stranger to Hawaii: Boiga irregularis, the brown tree snake. Originally from Australia and Indonesia, the snake arrived first on the Pacific island of Guam, thirty-three hundred miles west of Honolulu, shortly after the Second World War. The snake’s sphere of influence and notoriety has expanded steadily since. Prior to that fateful arrival, the only snake on Guam was the hapless Braminy. Today Guam hosts more brown tree snakes- more snakes of any kind, for that matter- per square mile than anywhere else in the world. This distinction has come largely at the expense of Guam’s native bird population, which the snake’s boundless appetite has almost entirely eliminated; the national bird of Guam, a flightless rail known as the koko, reigns from within the safety of a snake-proof pen in a rearing compound near the international airport.
In its native territory, the brown tree snake rarely grows more than three feet long on Guam, twelve-foot-long specimens are not unknown. Its bite, inflicted on two hundred or so people a year, is slightly venomous, akin to a bee sting. It also displays an irrepressible ability to climb, most notably onto power lines and into transformers, causing dozens of electrical outages each year, at a cost approaching a million dollars annually. Its toll on the local psyche is less easily quantified. Tales circulate of the snake that crawled in through the toilet; the snake that leaped from an automobile air-conditioning vent, sending the driver into a near-fatal swerve; and the snakes that attack infants in their cribs- lured there, local housewives attest, by the scent of mother’s milk.
And now, it seems, the brown tree snake has gained the ability to ﬂy. Since 1981, eight brown tree snakes have been found near the runways of Honolulu’s airports. To the best that experts can deter-mine, the snakes arrived as stowaways in the wheel wells of jetliners from Guam. A ninth specimen, last seen on the perimeter of the local air force base, also may have been a brown tree snake, but it slipped away before it could be positively identified. Over the centuries, Hawaii’s bird population has absorbed assaults by one introduced organism after another: humans with clubs, avian malaria, which arrived with imported cage birds and was transmitted by an introduced mosquito; Norway rates, which arrived incidentally aboard European ships; and mongooses, which were introduced intentionally in the late nineteenth century with the aim- misguided, as it turned out- of controlling the rat population. Today, nearly 40 percent of the bird on the U.S. endangered species list are found in Hawaii, an indication both of the uniqueness of Hawaii’s avian fauna and of its precarious situation. None of those birds are evolutionarily prepared for the likes of snakes.
Nor, presumably, are the eighteen thousand human visitors who arrive in Hawaii daily. A representative fraction of us had begun to gather in baggage claim: honeymooners, Japanese businessmen, grandmothers in leis, ﬂight-weary tourists in floral print T-shirts. We had received a warning of sorts on the incoming ﬂight. For a few moments, the map of Hawaii on the screen in the passenger cabin had given way to a video called It Came From Beyond, made by the Hawaii Department of Agriculture. A local celebrity appeared. Aloha! Hawaii is a special place; thanks for visiting! But Hawaii has other, less welcome visitors: insects, animals, plants, disease that can threaten local agriculture or native wildlife if they become established. So please be careful what you bring in. Better to declare it than to suffer a ﬁne. Better to confess. In baggage claim I watched as an avid beagle, outfitted in a green vest marked HAWAII DEPARTMENT OF AGRICULTURE, towed an amiable state employee around the room by a leash, through a sea of suitcases, tote bags, backpacks, bundles, and their ﬂagging possessors. The dog zigzaggs onward, nosily intent until at last he zeroed in on a small sensory paradise, a black handbag resting on the marble floor. The dog’s inspector spoke briefly with the bag’s owner, a Korean woman who eyed the beagle with terror. Reluctantly, she withdrew two oranges from the handbag and handed them to the inspector.
Eight brown tree snakes in twenty years would hardly seem to pose much of a threat. However, the biology of Boiga irregularis is sufficiently remarkable to concern and scientist, conservationist, or tourist administrator. The snake is nocturnal and, like any good predator, impressively hard to ﬁnd. It is also impressively handy; in 1993 a military officer in Corpus Christi, Texas opened the lid of a washing machine he had packed up and sent home several months earlier from his previous station on Guam. Inside was a brown tree snake, alive, with nothing for company or nourishment but a small pool of water. Thomas Fritts, the coordinator of the Brown Tree Snake Research Program for the United States and Guam, kept one alive in his office for a full year without once feeding it. Like many reptiles, a female brown tree snake can lay fertile eggs for several years after mating. Two dozed eggs a year for seven years equals more than a hundred and ﬁfty eggs, a hundred and ﬁfty new snakes capable of hiding, mating, and producing yet more eggs- all from a single snake. On Guam, our decades passed before scientists realized that the island was thoroughly snake infested, its bird population doomed, its ecosystem permanently altered. Today in Hawaii there is similar, urgent wondering: Perhaps they are but a visible handful of innumerable brown tree snakes that have slipped, and continue to slip, across Hawaii’s borders and into its foliage- apparent warning signs of what in fact is an encroaching, multiplying multitude of snakes. Perhaps below the Edenic surface of bougainvillea-lined streets and moss-draped rain forests, there lies a swarming Hieronymus Bosch world of brown tree snakes slowly gathering into a wicked, irreversible mass.
“Out of Eden: An Odyssey of Ecological Invasion,” Alan Burdick.