Geology of the Galapagos |
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The Galapagos Islands are a product of mantle plumes. Mantle plumes rise because they are hotter and less dense than the surrounding rock. These mantle plumes rise at about ten centimeters per year. As these plumes get closer and closer to the surface they start to melt which starts to produce magma champers. In some cases the magma is actually ablate push through the lithosphere which causes volcanic eruptions.
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Species Arrival |
Around five to ten million years ago the first tops of the Galapagos Islands appeared with no vegetation. When coming to these islands there are only two ways they could get her; by air or by sea. It is believed that many of the animals had come by "rafts." Although it is not likely that many of these rafts would make it, if only a few make it, then the biodiversity would have started. Penguins, sea lions and sea turtles all live in the waters could have just swam their way to the islands. The plants that are on the islands would have likely arrived on the islands by their seeds being carried through the sea. Wind is also thought to be a way of how other seeds, small insects, and tiny snails could have traveled to the island. Other birds could have just flown their ways to the islands.
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Feral Animal Eradication |
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Many years ago when pirates would stop at the Galapagos Islands they would pick up and store the Galapagos Giant Tortoise for meat and to make room for these tortoises they would leave their goats. These goats would then graze and start to destroy the habitat of the Giant Tortoise. To eradicate these goats we would use helicopters and arial hunting and track down the groups of goats and shoot and kill them. Some goats started to recognize the sounds of these helicopters and would actually hide under tree canopies. To get the rest of the goats, we would capture a goat and put a tracking device on it which then would lead us to these other groups of goats.
Goats were not the only feral animal to live on the Galapagos. Pigs were brought to the islands and would feed on hatchlings of the giant tortoise as well as the green sea turtle. The hunting of these pigs was done by poisoning carcasses. As well as goats and pigs, donkeys were also a feral animal on the Galapagos that caused many problems. Donkeys would crush iguana and tortoise nests as well as killing vegetation. |
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Biodiversity |
Plants: The vegetation on the Galapagos is almost desert-like because the Galapagos Islands are located on the Pacific Dry Belt. There are also about 825 introduced plant species on the Galapagos that were mostly introduced by humans. There are three major vegetation zones: the coastal zone, the arid zone, and the humid highlands.
Giant Tortoises: Tortoises arrived on the Galapagos Islands around 2-3 million years ago. It is thought that they floated over on "rafts." The giant tortoise is able to survive without food or water for almost a year. This made them a good food sources for voyagers who wanted fresh meat, but this then cause the exploitation of the species. Tortoises also struggle with predation of their eggs by rats, pigs, and ants. Tortoises are also able to communicate with each other, mostly through behavioral, but males are able to make loud groans. Iguanas & Lizards: There are seven different species of lava lizards on the Galapagos. The lava lizard is found on all of the major islands, but there are different color variations based on where they live and whether they are male or female. There are three different species if land iguanas on the Galapagos. Land iguanas can get up to three feet long and they tend to live in the drier areas of the islands. In 1975 feral dog packs had killed off a lot of the land iguanas on two of the islands. The Marine Iguanas on the Galapagos is the only lizard that feeds in the water. When the El Niño occurs the size of the marine iguanas is actually showed to shrink in size and then once foods is plentiful again they go back to their larger size. The El Niño, introduced cats, and different predatory birds are the main problems that can cause a decline in the iguanas population. Mammals: There are only 6 mammal species that are native to the Galapagos Islands. The Galapagos Sea Lion is the largest animal that is found on the Galapagos. Sea Lions have a very playful behavior but they can be very unpredictable so it is best to keep ur distance. Galapagos Fur Seals prefer cooler, rockier areas on the Islands. Because of their thicker fur coat they were hunted in the 1800s to almost extinction, but were able to come back. There are only four of the seven species of Rice Rats still on the Galapagos Islands today. These species are only found on the land were there are no humans that live there. There are two bat species found on the Galapagos but there is not much known about them. Dolphins and whales are the last group of mammals found by the Galapagos. They are aquatic mammals that have a layer of blubber that helps to keep them warm. When looking at the different groups of these mammals there are the baleen whales which consist of humpback whales. There are also the toothed whales which consisted of the sperm whale, killer whale, pilot whales, and the false killer whale, as well as the bottle-nosed dolphin and the common white-bellied dolphin. Birds: There are 29 land birds in the Galapagos Islands and thirteen of these species are known as Darwin's finches. The other land birds consist of mockingbirds, hawks, doves, flycatchers, rails, and martins. There are also many different sea birds of the Galapagos like the Blue-footed Booby, Lava Gulls, Galapagos penguin, etc. |
Mangroves |
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Mangrove forest are such a biodiverse place. In the waters surrounding these mangrove forests there are many different species that live and survive among the mangroves. Some of these species are the upside down jellyfish, the sea cucumber, horseshoe crabs, the mangrove snapper and different sponges. Mangroves are also home to many different insects, reptiles, birds, and mammals. They provide a wintering habitat for many migratory birds. Mangroves also improve the water quality, by the roots are able to slow the waters down and trap sediments and then keeping waters clearer. Mangroves also provide protection against storms and high winds along coasts.
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