Tour boats brought more than 170,000 tourists to the Galapagos in 2008. More and more people have moved to the islands to support the tourism industry, putting pressure on the natural environment. (Submitted by Micah Dubinsky)

If Charles Darwin could revisit the Galapagos Archipelago on his 200th birthday this Thursday, he would find some of the scattered volcanic islands hearteningly untouched but others tragically damaged since he first set foot there on Sept. 15, 1835.

Darwin, who was born on Feb. 12, 1809, proposed one of the fundamental ideas of modern biology — natural selection — after his visit to the South American archipelago 1,000 kilometres off the coast of Ecuador aboard the HMS Beagle.

Though he wasn't impressed with the barren, cratered landscape he first saw, the 26-year-old biologist soon learned that, in fact, the islands were teeming with unique living things — from marine iguanas to unusual mockingbirds. Each was carefully adapted to environments that ranged from deserts bristling with cacti to steamy, lichen-covered forests.

Darwin later said his theory of natural selection, which explained how living things could evolve and change over time in response to their environment, was the result of his observations of living things in the Galapagos.

Sadly, the struggle for survival that Darwin witnessed on the islands has become even tougher for their plant and animal inhabitants. Humans have imposed a new kind of selection. In 2007, just two years before Darwin's 200th birthday, UNESCO added the Galapagos to its list of world heritage sites in danger. This past December, travel publisher Frommer's named the islands one of their "11 places to see before they disappear."

'A Mecca for ecologists'

Biologists and tourists are drawn to the Galapagos because of its unique plants and animals, such as this marine iguana. (John Smol)The plant and animals that live on the archipelago's 13 large islands, its six smaller ones, its scores of islets and rocks and in the waters that surround them still inspire fascination in visitors like Queen's University biologist John Smol.

"It's sort of like a Mecca for ecologists and biologists," said Smol, who returned one week ago from his first trip to the islands.

He had lectured about their inhabitants for 20 years, but seeing them was different, he said.

"You see these marine iguanas jumping in the water, swimming … you don't think of lizards in the ocean, for example," Smol said.

Many of the animals still have no fear of humans, having lived for generations without encountering any.

"I was snorkeling, and a big sea lion came within a few centimeters of me, and it kind of freaked me out," Smol recalled with a laugh as he described his trip as a lecturer on a cruise ship filled with alumnae from universities across North America.

Today, evolutionary biologists continue to flock to the Galapagos. Christine Parent, a biologist who is originally from Trois-Rivières, Que., spent much of the past decade trying to figure out how there came to be 80 species of small land snails living all over the islands — from the desert-like lowlands to the tropical highlands. Each is a different shape, size and colour, and many are starting to disappear.

Canadian researcher Christine Parent studied land snails on the Galapagos. She is shown here in front of the Alcedo volcano on Isabela island. (Courtesy of Christine Parent)Parent, who studied at McGill, Carleton and Simon Fraser universities before becoming a postdoctoral researcher at the University of Texas, said she was inspired to pursue biological research in the Galapagos after visiting the islands at age 17 while on a high school exchange in Ecuador. She saw dramatic changes on the handful of inhabited islands between her first visit and her most recent visit in 2005, about a dozen years later, she said.

Sand walking paths and small streets had given way to paved roads roaring with cars, and small cottages that housed a few thousand people were replaced by sprawling residential and commercial complexes in the archipelago's largest community, Puerto Ayora on Santa Cruz island.

"It's really a different town now," Parent said.

She thinks Darwin would be astonished if he saw Santa Cruz island today.

"He would be in shock," she said. "He would be a bit traumatized, I guess, by the change."

173,000 tourists in 2008

Most Galapagos communities once consisted of small villages with sand roads, like Puerto Villamil, but some have now grown into towns full of cars and large buildings. (Christine Parent)The Galapagos' ecological reputation has drawn increasing numbers of tourists to the islands. More than 173,000 visited in 2008, up from just 40,000 in 1990, according to the Galapagos Conservancy, a group based in Fairfax, Va., that is trying to restore and protect the islands.

As the number of tourists has grown, so has the number of people who live on the islands providing goods and services to support the tourism industry. The population is now at 30,000, said Johannah Barry, president of the Galapagos Conservancy.

That has put a strain on scarce resources such as drinking water and made it difficult to manage waste and sewage.

"Species are overfished; native wood is being used for building; sand is being dug up from beaches to mix in with cement," Barry said.

Invasive stowaways

Extermination programs have mostly eliminated goats and other domestic animals that have hurt populations of native animals. This photo, taken about five years ago, shows some of the last goats at Cerro Azul, Isabela island. (Christine Parent)Even more of a threat are the invasive plants, animals and diseases that are stowing away among the growing shipments of food and supplies heading to the islands. These include cottony cushion scale insects that have devastated local citrus trees and animal diseases such as distemper and avian malaria.

"These are biological agents for which Galapagos was not prepared and for which its plant and animal life was not prepared," said Barry.

Dogs, cats, pigs, goats and traffic have devastated populations of birds who had never before seen a mammal predator or a car.

Parent believes invasive plants are the worst threat.

"They really modify the habitat, and this is what is probably causing some of the snail [populations] to go down dramatically and all the invertebrate populations," she said.

There is some good news, however. About 97 per cent of the archipelago's land area is protected by a park designation, and about 95 per cent of the species that lived on the islands before humans arrived still remain, Barry said.

The Ecuadorian government and conservation groups have been trying their best to restore some of the threatened species — from giant tortoises to the mangrove finch — by counting their wild populations, breeding them in captivity and re-releasing the offspring. Successful programs have also managed to exterminate introduced pigs, goats, donkeys and other damaging domestic animals on many of the islands.

The Ecuadorian government announced in 2007 that it would make the preservation of the Galapagos a national priority and has since asked for reports on the state of the islands.

"A big challenge for decision makers and for educators in Galapagos is to help this growing population understand that they are living in an extraordinary place … This is a World Heritage site …This is an archipelago like no other," Barry said.

No action can take place until after an upcoming presidential election, but Barry said president Rafael Correa, who is running for re-election on April 19, has expressed his commitment to ensuring the Galapagos are protected.

"There's a lot at stake, and the president gets that … He recognizes — and the conservation community recognizes and Galapagos National Park recognizes — that the Galapagos really … [are] in danger."