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Wafer Bay from high on Cocos. Wafer Bay from high on Cocos.
Assault on Cocos
by Peter Tyson
October 3, 1998

The panga bounced through a choppy sea into Wafer Bay. Ahead of us, jungle- draped hills leaned over the modest National Park settlement, their lush verdure cascading down into the bay. I would climb those hills and more like them in my bid to reach the summit of Mt. Yglesias, the island's highest peak at 2,092 feet (see Explore the Island). Holding my pack high over my head, I dropped into four feet of water and pushed through the surf toward shore. My assault of Cocos had begun.

Another assault on the island began over 200 years ago and continues today. In 1793, while studying the region's whale fishery, Captain James Colnett paused at Cocos Island on his ship Rattler. At the end of a brief and rainy visit, he wrote: "We were much wearied during the four days we passed off this island, and prepared to quit it. We therefore took on board two thousand coconuts; and, in return, left on shore . . . a boar and a sow, with a male and female goat." As this passage suggests, Colnett was a generous sort, and he did what he did—which also included sowing garden vegetables—"for the benefit and comfort of those who might come after us." He had no idea that he was sowing ecological disaster on the island.

The pigs and goats proliferated, as have feral cats, white-tailed deer, and that ever-present stowaway, the rat. Non-native plants have also gained a foothold. August Gissler, the would-be colonist of Cocos Island (see Legends and Lore), raised citrus trees and coffee plants, whose descendants have spread throughout the Wafer Bay watershed. Even the eponymous coconut palm itself is exotic to "Coconut Island."

To varying degrees, these introduced species are taking their toll on Cocos. Felipe Avilés Briceño, an amiable, heavy-set man who lives at Wafer Bay and is the coordinator of operations for the Cocos Island Marine Conservation Area, told me that the endemic Cocos finch eats the coffee beans, thereby spreading the seeds. Only a certain vine that tends to strangle the coffee plants keeps them from infesting the island. Avilés said the cats hunt native birds, and the rats chew the bark at the base of native trees, killing them. As in Hawaii, however, it's the pigs that are wreaking the most havoc. They root up the soil searching for worms, their chief source of protein. Claudine Sierra, one of three biologists I joined on the climb, found that these gaping wounds in the hillside leach nutrients and increase erosion seven times over natural rates. There is now talk of eradicating the pigs.

Claudine Sierra and Roberto Plaza Illingworth pause along the trail. Claudine Sierra and Roberto Plaza Illingworth pause along the trail.

Three hours after leaving Wafer Bay, we reached the flank of Yglesias. The route was exhausting: up those near-vertical hillsides above Wafer, along several ridges in the center of the island, and up and over the second highest summit, Cerro Pelon, from which I could see the Undersea Hunter far below, a white speck in the surrounding cobalt. We were sweaty, stinky, filthy, and tired, but exhilarated, for Cocos' legendary rain had held off, and the forest had assumed a primordial beauty. We walked through twilit passages of twisted, moss-draped trees that gave way in a breath to bright glades of tree ferns. Bromeliads by the score festooned the branches of stunted "iron trees," so-named for their dense wood. The epiphytes' curled white leaf axils littered the ground like bleached bones. All together, the forest—exotic, dripping, and fog-bound—looked like some relict from a lost age.

Yet it was strangely silent. Where were all the birds and insects whose calls make your typical rainforest an intricate web of acoustic niches? The only bird calls I heard were the occasional squawk of a frigatebird or booby high above the forest, or the sweet peep of a snow-white fairy tern hovering low before our faces. I heard no insects at all and saw almost as few. There were no butterflies or beetles, no spiders or even spider webs. Every time I thought I caught sight of something moving, it was just a leaf flicked by a falling drop.

The reason is that Cocos is a geologic infant. It was born only two million years ago in a rush of steaming lava thrust above the waves. Compared to more aged rainforests, that on Cocos is species-impoverished. It has just over 200 kinds of plants and 74 kinds of birds—slim pickings for a rainforest. It has no native mammals, no frogs or other amphibians, no snakes. Most rainforests also have a host of endemic species, those found only there. Cocos has but a few, including two lizards and just three species of birds - a flycatcher, a cuckoo, and a finch. The island simply has not had time to evolve more.


Alvaro Farías Garita on Mt. Yglesias. Alvaro Farías Garita on Mt. Yglesias.
"It's a place where time stands still," said Alvaro Farías Garita soon after we left the summit behind. A dreamy, barefoot biology student who is assisting Sierra in her study of the feral pigs, Farías had lead me off the main trail to the wreck of an American B-24 that had crashed on the mountain in World War II. The plane was on its way to the Galapagos when preternaturally bad luck had it strike the only piece of land within 300 miles, killing all 11 servicemen aboard. Buried beneath a tangle of vines, the wreckage was strewn over a steep, inaccessible slope; the only part I could recognize was the giant propellers, which lay side-by-side in the dirt as if on display. Nearby was a simple wooden cross: "To All of You, RIP, 1943."

For me, the plane symbolized another type of assault on Cocos, the human one. The wreck is one of the island's principal tourist attractions. At present, Cocos gets only about 2,000 visitors a year, of which, Felipe Avilés told me, only one in a 100 makes the trek up the mountain. (The moldy visitor's book at the summit had fewer than 20 signatures since March.) But last December the United Nations declared Cocos a World Heritage Site, and the island's natural treasures, both above and below water, have received substantial press in recent years. Tourism is sure to increase. And Cocos is about as prepared for it as it was for the pigs.

Enter Roberto Plaza Illingworth. He's the third biologist I joined on the climb. Based at Latino University in San Jose, where his specialty is natural resource management, Plaza is undertaking the first-ever study of the park's carrying capacity. While I concentrated on watching my step during our climb, Plaza was busy measuring the length, heading, and altitude of the trail from Wafer Bay to the top of Yglesias. His tools: a measuring tape, compass, and altimeter. He's also studying other factors. How much rainfall should a visitor expect during an average day? Are the trails well maintained? How difficult are they? Does the park need more rangers? By December, he'll present the park service with recommendations and a simple figure of carrying capacity: allowable number of visitors per day.

Plaza's measurements took time, so that night we camped along a streambed in the heart of the park. Soundless during the day, the forest came alive after dark. With a bottle of red wine as accompaniment, we enjoyed a moonlight sonata by a bevy of bugs, as the moon dashed in and out of clouds overhead. Our delight in the dry weather did not last long; in the wee hours, it began to rain. I know, because the roots and rocks pushing up beneath my one-man tent did not allow for much sleep. I finally drifted off, but at dawn I was awakened by a wet feeling under my back: water was seeping into my tent.

Leaving the others to sleep, I packed up and headed down the trail. The rain increased throughout the day, until it was an utter tropical downpour. But it was warm, so I took an hour-long detour to a 100-foot waterfall and had a delicious swim in the pouring rain. By pure serendipity, I came upon the others as soon as I rejoined the main trail, and we finished Plaza's survey together. The final tally: 18,246 feet from the summit of Yglesias to the park service buildings at Wafer Bay, a round-trip of about seven and a half miles.

Our assault was over. If only the same could be said of the other one.

Peter Tyson is Online Producer of NOVA.



Hammerheads or Bust (Sept. 23)
Get Used To It (Sept. 25)
Nature Reigns at Cocos (Sept. 27)
The PIG and the Process (Sept. 29)
Hammerheads Sighted (Oct. 1)
Assault on Cocos (Oct. 3)
The Director's Cut (Oct. 5)
Swimming with Whitetip Reef Sharks (Oct. 7)
The Magnificent Seven (Oct. 9)
The Search for Lake Cocos (Oct. 11)
Courtship of the Marbled Rays (Oct. 13)
Of Booby and Beebe (Oct. 15)
Taken by Surprise (Oct. 17)
"This is Cocos, This is Cool" (Oct. 19)


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