A day full of amazing things! We started with a walk through Puerto Ayora to the Charles Darwin Research Station. This facility operates breeding programs for most of the species of Galapagos tortoises. We learned about the process of collecting eggs from nests in the wild and how they are cared for until they hatch. Once a tortoise egg begins to develop, it must be kept with the same end up or the embryo will die. Scientists have also learned that if the eggs are kept at 28 degrees Celsius the entire clutch will be females. At 29.5 degrees Celsius they will all be male. This knowledge helps scientists maintain a gender balance which is especially important for those species with few breeding adults. The tortoises do not reach sexual maturity until the age of 25.
Once the tortoises hatch they are numbered on their shells. The numberings are color coded by island so scientists can tell which species is which. For the first 2 years of their lives, the baby tortoises are kept in small enclosures with a fine mesh covering to keep out invasive predators like rats. From 2 to 5 the babies are moved to large pens with a mix of species (another reason the color coding is important). Once they are 6, the tortoises can be released into the wild on their home island.
There is another mixed species enclosure at the research station containing males from various species. It is interesting to see the diversity of shell and body shapes side by side. The dome shelled species have short legs and necks and evolved on islands with wetter climates and more vegetation close to the ground. The saddleback varieties have long necks and legs. They come from the drier islands where it is necessary to reach up in order to get enough food. Perhaps the most striking thing about this pen is the realization that every tortoise in it is well over 100 years old.
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Next we traveled to the Bosque to view Los Gemelos. This was our first trip into the Highlands. The coastal areas of the islands are all fairly dry, but the higher elevations have a much wetter climate. It was interesting to watch the vegetation change as we drove. Los Gemelos, or the Twins, are a pair of collapsed magma chambers. At some point in the distant past, magma pushed up through the Earth's crust, but did not reach the surface. When the volcanic activity waned the chambers emptied. Without the pressure of the magma underneath, the roosf of these chambers collapsed. These are found at the highest elevations on Santa Cruz in the scalesia forest. The scalesia look like trees and can grow to a height of 20 feet or more, but they are actually in the daisy family.
After visiting the Twins we took a walk/crawl through a 400 meter lava tube. Lava tubes gotten when the outside of a lava flow hardens while the lava inside continues moving. When the eruption ends and the lava in the tube has flowed away, the tunnel remains. This particular lava tube was in some places 30 feet from to to bottom. In one place though it was only about 24 inches high and we had to crawl through the gap.
The day ended with a stop at Rancho Primacias. This is a working cattle ranch that also functions as a giant tortoise preserve. The ranch borders the national park and several years ago the owners decided to embrace the tortoises rather than work to keep them out. They loosened the bottom wire in the fences which allows the tortoises to come and go as they please but still keeps the cattle where they are supposed to be. There is a visitor center and a large park where people can wander among the tortoises. This is not a zoo, or breeding center, the tortoises here are wild. Rancho Primacias shows that it is possible for human and natural communities to coexist.
This type of harmonious coexistence is on display all around the Galapagos (although they have their problems as well) and should serve as a model for how humans can - with commitment and thoughtful, science-backed planning - live alongside the animals we are too often just displacing.
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