Energy Cycle in the Gal á pagos

Energy Cycle in the Galápagos How might disruption at each level of the energy cycle affect an ecosystem?

Galapagos Islands – 600 miles west of Ecuador; volcanic archipelago

Largest human population

Galapagos Original Energy Cycle 3rd lvl consumers – None 2nd lvl consumers – seals, birds, fish, bats, penguins 1st lvl consumers – giant tortoise, iguana, rice rats, bats, birds, fish Producers – 600 species of plants

Galapagos Current Energy Cycle 3rd lvl consumers – 2nd lvl consumers – 1st lvl consumers – Producers –

Introduction of new species • Currently only 500 native plant species; over 700 introduced plant species. • British navy introduced goats to the islands in 1700’s; Spanish imported dogs to kill the goats • When Spanish attempted to colonize Santa Maria, they transferred dogs and goats to the other islands • In 1959, fishermen introduced one male and two female goats to Pinta island; by 1973 the National Park service estimated the population of goats to be over 30,000

Introduction of new species • Dogs and cats attack flightless birds and destroy nests; pigs destroy nests of turtles, iguanas and tortoises & destroy vegetation searching for insects • Non-native animals currently include goats, pigs, dogs, rats, cats, mice, sheep, horses, donkeys, cows, poultry, ants, cockroaches

Introduction of new species • Black rats stopped reproduction of giant tortoises on Pinzon for 50 years; displaced native rat population • Pigs have caused the disappearance of tortoises from two of the 19 islands

Energy Cycle in the Gal á pagos