Galapagos islands - effects of human activities

• Charles Darwin visited the Galapagos island in 1835
• Native species of Galapagos
• Darwin's finches
• Giant tortoises
• Land iguanas
• Galapagos are the best conserved and have the highest number of native species.
• For these reasons, they are a world heritage site since 1978.
• Unfortunately, 50% of vertebrates and 25% of plant species are endangered.
• The population of Galapagos has grown in response to developing tourist trade
• Effect of human activities on the animal and plant population in the Galapagos Islands
• Habitat disturbance
• increased population has place demands on water, energy and sanitation
• more waste pollution
• demand for oil has increased
• an oil spill in 2001 had adverse effect on marine and coastal ecosystems
• increased pollution, building and conversion of land to agriculture have caused destruction. (Forests of scalesia trees and shrubs has been eradicated for agriculture)
• Over exploitation of resources
• harvesting whales and seals to sell internationally
• giant tortoises een killed and eaten (200, 000 tortoises taken in less than half a century)
• fishing for exotic species in 1990s have depleted population
• depletion of sea cucumber population has a drastic effect on under water ecology
• demand for shark fin had led to death of 150 000 sharks each year
• introducing new species
• deliberately brought in
• humans
• goats
• one of the most damaging species
• eats Galapagos rock purslane
• out competes tortoise for grazing and trampling on their food supply
• changes habitat reduced tortoise nesting sites
• cats
• fruits and veg
• unintentionally brought in
• insects
• diseases (malaria, bird flu etc)
• Charles Darwin research centre adopted strategies to prevent the introduction and dispersion of introduced species
• they have instigated a quarantine system, they search boats for foreign species
• natural predators have been exploited e.g. ladybirds to control a scale insect
• culling wild goats and pigs
• educating local people
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