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Saturday, 17 December 2016

Santiago and Bartolome Islands

Santiago - also known as James, and/or San Salvador - was a favourite island for pirates and whalers, and had a long human history - near Puerto Egas, not far from where we landed, salt mining operations were attempted. Great effort was put into extracting salt from the crater though little profit was made and the venture was abandoned. We wet-landed on a black sand beach following a longish trail, seeing lots of land and marine iguanas, cacti as well as Darwin's Finches - see later blog on these specifically, Galapagos Doves
(Zenaida galapagoensis)

- its curved beak allows it to feed on seeds picked from the ground, mainly of the Opuntia cactus. Cactus pulp forms part of their diet and is probably their main source of water as the dove is found in the more arid parts of the main islands. The dove is most commonly seen on the ground where it forages for seeds and fruits. Even when disturbed its reluctant to take to fly off. One lovely fact - it seems 'Natural Selection' has given rise to softened cactus plants' spines, allowing the dove to pollinate the flowers - remember there is only one hard working bee in Galapagos ...

the Carpenter Bee (Xylocopa darwinii)!

Galapagos lava lizards (Microlophus albemarlensis),which feed on beetles, spiders, snails and insects such as ants. The male Lava Lizard may have two, three or more mates in a harem, and they can be very aggressive in defending their territory and will stand with front extended, on all fours, usually sideways to their opponent to maximise their apparent size; extend the scales on their backs, and bob up and down.




We reached the seal grottos, where Tim Guiness lost his camera case briefly! We watched the Galapagos Fur Seals (Arctocephalus galapagoensis - see footnote) play and then we returned for breakfast, cooled off and then went to the beach for a snorkel, Margaret too.

After lunch I went deep-water snorkelling, along the cliff and the famous tuff cone. Enjoyed the company of turtles and penguins!

Then it was time for our climb up the staircase to take in the famous viewpoint, with plenty of opportunities for photos.



Footnote on Galápagos fur seals. They live in large colonies on the rocky shores. These colonies are then divided up into territories by the female seals during breeding season which is Mid-August to mid-November. Every mother seal claims a territory for herself and breeds her pups here. This seal has a longer nursing period than any other species of seal. Females have been known to nurse up to three year old pups, but usually it takes somewhere from one to two years before the pup leaves and lives on its own. The reason some pups take longer than others to develop is because when there is a shortage of food, which can be caused by El Nino, the mothers can not properly nourish their young. El Nino has a devastating effect on the fur seals of the Galápagos. During El Nino years food supplies can drop extremely low, causing many seals to die from starvation. This is because El Nino raises the temperatures of the waters around the Galápagos, causing the seals’ food supply to migrate to cooler water. During the nursing years, females will leave for up to four days at a time to forage for food. They then return to rest and feed the pup for just one day and then return back to the sea and repeat the process. While the mother is away, the pup must be careful because other female seals are extremely violent against pups that are not their own. Female seals will defend their territories to the death. They do not want to lose their area because they will not be able to breed then. If a pup wanders into another female’s territory, the female sees this as a threat and will attack or may even kill the pup. The Galápagos fur seal feeds primarily on fish and cephalopods. They feed relatively close to shore and near the surface, but have been seen at depths of 169 meters. They primarily feed at night because their prey is much easier to catch then. During normal years, food is relatively plentiful. However, during an El Nino year there can be fierce competition for food and many young pups die during these years. The adult seals feed themselves before their young and during particularly rough El Nino years, most of the young seal populations will die.

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