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Overnight we did our longest crossing to Genovesa Island about 80 km to the northeast of Bartolomé. It is the most remote of the large islands. It is only 14 km² and only reaches a maximum elevation of 76 m. It is named in honour of Genoa Italy birthplace of Christopher Columbus (in Spanish Speaking countries, he is Cristóbal Colón). Its remoteness prevented all lava lizards, which are numerous on all the other islands, from reaching it along with giant tortoises and land iguanas. There are marine iguanas but they are the smallest in all the islands and jet black without reds or any other colours that are seen on the other islands. Genovesa is another of the islands whose finches have been extensively studied by the Grants and their graduate students for many years.

Our first adventure was a snorkel along the crater walls. On one side were basalt cliffs teaming with fish and other marine life. To the other side was the crater that dropped off to depths of 200 m or more and appeared as various shades of blue. As we swam, out of this blue abyss appeared huge hammerhead sharks! I have to say that they were magnificent. The experience was not unlike my first close encounter with a grizzly bear. Hammerheads can be very aggressive but they generally seem to be indifferent to people in Galápagos. I was told that there have only been 4 shark attacks in 40 years. Being in the water with these huge predators (up to 3 m in length) was an experience that I shall not forget. Seeing then with 15 other people also made me acutely aware as to why fish swim in schools. Someone may be eaten but likely not you.

We motored along the crater walls in the Zodiac to see northern fur seals. These are misnamed and actually are sea lions. They hunt at night and at depth so their heavy fur coats and large eyes are an asset. They are less likely to be attacked by sharks at night also. We ascended to the surface of the Island via Prince Phillip’s steps (Phillip of Spain, not Queen Elizabeth’s husband). This break in the crater wall is a fissure in a mass of basalt flow that is slowly breaking away from the crater wall and will eventually topple into the sea. I was happy to have come and gone before it happened. In fact, the crater and open sea margins are unstable around the island and tensional fissures are everywhere. The surface of the island is all ropey-looking pahoehoe lava flows. The peninsula southeast of Prince Phillip’s Steps is covered by bird colonies. Here, red-footed boobys dominate. There are twice the number of red-footed boobys than blue-footed and Nasca boobys combined in the world. The red-foots feed much farther out to sea than the others. The air teamed with storm petrels while the minor frigate birds were busy mating (two species are present in the islands, magnificent and minor). The males have a large red bladder-

Red footed booby, Genovesa Island Photo by Lionel Jackson

Male frigate bird displaying its puffed out throat sack to attract a mate

Photo by Lionel Jackson

like sack in their throats. They inflate this and sit in the brush trying to attract a mate. The girls look them over and choose the ones with which they want to mate. Following lunch and siesta, we motored to the one beach along the crater and climbed along the cliffs. There, I saw the Genovesa version of the prickly pear cactus. Without any tortoises or land iguanas to eat it, the spines of the cactus were no longer needed and a waste of plant growth that could be diverted into seed production or other plant growth or functions that

Low, spreading growth habit of spineless pricky pear cactus in land iguana and tortoise-free Genovesa Island.

White sand is the by-product of coral-munching parrot fish Photo by Lionel Jackson

enhance survival and successful reproduction under the local conditions so natural selection favoured virtually spineless varieties. The spines on these plants are as soft as the bristles on a baby’s hair brush. The cactus is low and spreading although the climate is as arid as Plaza Island where the same plant has the form of a tree and deadly spines.

Marine iguana feeding on algae coating a lava block (centre of photo). Photo by Lionel Jackson

There was a large tide pool surrounded by mangrove trees in this area where we could watch a marine iguana dine on algae. They grip onto the lava with their large claws. Their legs play no role in swimming: they use only their vertically flattened tails to propel themselves along with the legs straightened along their bodies. The Genovesa marine iguanas are the smallest subspecies that we saw in the islands.

The beautiful white beach where we made our landing was made of coral fragments. These are created to a significant degree by parrotfish that eat coral and excrete sand. We could often hear them at work while snorkelling.

We returned to the ship for our last dinner together. We enjoyed a particularly beautiful sunset over Darwin Bay. We had a farewell cocktail and enjoyed a special cake. We weighed anchor and headed toward Baltra Island.