Among those fascinated by the Galápagos Islands, which Charles Darwin made famous, is an Irish scientist who conducts research at the Charles Darwin Research Station on Santa Cruz Island, writes DICK AHLSTROM.
THE IGUANA shuffled slowly along the shore, watching for what might wash up at the water’s edge. The great Pacific spread out before the creature, but it didn’t notice, cautiously watching instead a young man who crouched a short distance away. He remained motionless but for his hand, which scribbled hurriedly into a small notebook he kept balanced on his knee, the page’s simple heading, Santa Cruz, Galápagos Islands.
So might a young Charles Darwin have recorded his first observations of the marine iguana that are found throughout the Galápagos island chain off South America.
Perhaps no other place on earth is as important for our understanding of evolution, because the observations made there more than 170 years ago by Darwin inspired him to develop his ideas about natural selection and the origin of species.
The Galápagos can still inspire today, as they do a young Irish scientist there who now follows in Darwin’s footsteps. “This very much makes you feel like a young Charles Darwin working here,” says Dr John Paul Tiernan, speaking from his home on Santa Cruz island.
HE JOINED THE Charles Darwin Research Station there back in November 2007. He believes he is the only Irish scientist working in the Galápagos and may also be the only Irish person currently living in this volcanic island chain, located almost 1,000km off the coast of Ecuador.
The islands, officially know as the Archipiélago de Colón, make up the Galápagos Province of Ecuador and are part of its national park system. The archipelago includes 15 big islands, four of them inhabited and about 100 rocks and islets.
The islands came to prominence after Darwin's visit in the early 1830s while he served as ship's naturalist on board HMS Beagle. The animal and bird species he saw there and recorded in meticulous detail provided the evidence for our understanding of how species separated from one another can diverge and evolve to form wholly new species despite having a common origin.
Tiernan’s own sojourns began when he landed in Ecuador to teach marine biology at the Universidad San Francisco de Quito. He soon sought passage to the islands however to work at the research station in Santa Cruz. He has been involved in shark monitoring and tagging, sealion monitoring and coastal clean-up and recycling initiatives.
He is now part of the research station’s marine ecological monitoring group, providing baseline measurements of the algae species that grow on the shoreline in the intertidal space between high and low tide. This information will help to develop conservation management strategies for the Galápagos marine reserve.
Knowing about algae will tell the researchers much about how the Galápagos ecosystem has changed over the past 30 years, Tiernan says. The last study was done in the 1970s when the island chain population was only 2,000. Now it stands at about 40,000 and continues to grow.
“The islands have changed dramatically over this time,” he says. Increased fishing has altered the predator-prey balance and the rising population also puts pressure on the wider ecosystem. “The abundance of the algae can tell you things about changes to the ecosystem,” he says. “Some algae species have become extinct in this time, which is an unusual thing when you speak about Galápagos.”
There is much research work to be done there and much remains to be learned, he says. “Absolutely. The greatest study of the finch was in the 1970s and 1980s when their evolution was studied over very short time periods.”
IRONICALLY, DARWIN IS closely associated with the finch species on the islands, but in fact he garnered incomplete information from them. “Some of the animals named after him, for example the finches, he completely overlooked,” Tiernan said.
“He sampled them but he did not label his samples to know which island they came from.” He learned more from the local mockingbirds, Tiernan adds.
The iguanas need more intensive study as do the island’s insect populations, he believes. “We continue to find new species and this leads you to the question of introduced species.
“There are now twice as many introduced as native species of insects. There is a lot to be learned about the Galápagos still,” he says.
He is a long way off growing tired of what the islands can provide in the way of research. “It is very easy to motivate yourself to do ecological research here.” he says. A lot of the questions we are asking here are broad environmental questions.
“It is right outside your door. As I speak I am looking out at an iguana on the pier.”
On the Radar will resume next week