Darwin’s finches (also known as the Galápagos finches) are a group of about 18 species of passerine birds. I just learnt the word passerine. It sounds impressive but just means that they perch. This includes nearly half of all bird species. The thing about the finches is that Darwin noticed there were distinct species on different islands. In particular, there was a lot of variation in beak size. This is a classic example of adaptive radiation, which is the rapid evolutionary diversification of a species that occurs when its members occupy different habitats. The birds are thought to have evolved from a single finch species that came to the islands more than a million years ago. I tried to photograph a few of them.
Santa Cruz Island hosts the largest settlement in the Galapagos archipelago. Puerto Ayora, population 18,000. We spent the whole day on the island visiting various sites. First of these was the Charles Darwin Research Station. This is an interesting place that principally conducts scientific research and environmental education for conservation. The Station has a team of over a hundred scientists, educators, volunteers, research students, and support staff from all over the world. We skipped past much of this stuff and were taken straight to the tortoise sanctuary.
In the sanctuary, in fenced off areas, were baby tortoises, adolescent tortoises and great big tortoises. They can live to be well over 100 years old and weigh over 400 kg. They are the largest terrestrial cold-blooded animal. Like the finches, they have diversified across the islands. Darwin’s observation of the differences was another contribution to the development of his theories. The tortoise nearly went extinct in the 20th century as a combination of habitat clearance and exploitation. In particular, they were very useful on the ships of old. Before refrigeration it was difficult to keep food fresh on long voyages. Live animals were often taken but these still had the problem that they needed to be fed and watered. A tortoise, however, can survive for up to a year on its stored fat. The sailors of old would collect a rack of giant tortoises. They were not difficult to catch. Then each week they could crack open another tortoise for fresh meat. From an estimated 250,000 in the 16th century, they were down to 15,000 in the 1970s. Elsewhere, giant tortoises, that were common in prehistoric times, have all gone extinct.
These days, the tortoises are doing much better. The introduction of goats was particularly bad for the tortoises because the goats ate all the vegetation. There are now very few goats in Galapagos but this did require some rather drastic action including the use of helicopters to hunt and shoot them. On Isabella island this accounted for some 150,000 goats by 2006.
A tortoise was spotted on Pinta island in 1971 that turned out to be the last remaining individual of a subspecies. They called him Lonesome George. For decades he was known as the rarest creature in the world. George serves as an important symbol for conservation efforts in the Galápagos Islands and throughout the world. He was relocated the sanctuary and a worldwide search was put in place to find him a mate. It never worked and in 2012 he died of natural causes. He was frozen, shipped to the USA, stuffed and, eventually, sent back again. We were shown the result of the taxidermy in a special room at the sanctuary. It is a big stuffed tortoise. I was not impressed but then I have always found taxidermy a bit revolting.
Sanctuary done, we went to a sugar cane farm. In quick succession we were shown how to press sugar cane. How to boil the resulting liquid down to molasses. How to ferment the molasses and how to make moonshine in a homemade still. This was all fairly interesting but the highlight was to try some of their hooch. The farm also grew cocoa beans. I spotted some pods growing on trees which is the first time I had actually seen cocoa pods growing. We also spotted an owl in the roof above the still. He seemed to be quite content keeping an eye on proceedings.
Final event of the day was the wild tortoises. Galápagos tortoises occur in different subspecies on the several of the Galapagos islands. We went to see an area where the Santa Cruz tortoises run around. Apparently they were all coming up from the coast because it was the mating season. When I say “run around”, it is kind of a relative term. Some of the tortoises did move but it would appear that you do not get to live to 177 by rushing around. Most of the day they eat grass. In the morning, they will stand up and move about half a metre forward. Then, after settling down again, they eat all the grass they can reach with their long necks in a semi-circle in front of them. After a short rest, they stand up and the process is repeated. Watching wild tortoises is interesting rather than exciting.
