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| | | Island Ecosystems |
Maintained by NOAA
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| | Types of island ecosystems | | |  An island is a body of land, smaller than a continent, completely surrounded by water. Plants and animals of island ecosystems have many distinctive features, often related to the type of island: - old continental islands e.g. New Caledonia and New Zealand, originally part of a continent
- oceanic islands, generally volcanic and short lived e.g. Hawai'i
- coral atolls (see photo of Palmyra Atoll)
- small, numerous islands e.g. red mangrove islets in the tropics, sand islets of the Caribbean and Indian Ocean, and
- barrier islands parallel and close to the mainland coast.
| | Photo title: Palmyra Atoll, Pacific Ocean | | Photo credit: Kim Cobb, Scripps Institution of Oceanography | | | | Island biogeography | | |  Island ecosystems have been studied because they are simpler than ocean ecosystems. Even clusters of islands are simpler to study. Islands provide natural “experiments” for research because of their number, variation in shape, size, degree of isolation and ecology. Oceanic islands near continents may have continental plants and animals. More isolated islands may have endemic species. One of the key relationships in island biogeography is the area-biodiversity curve. Generally the larger the island, the more diverse the plants and animals. To put it another way, environmental diversity is correlated with island area. | | Photo title: Bahia Azul, Panama, a great chaenopsid collecting site | | Photo credit: P A Hastings, Scripps Institution of Oceanography | | |  More recent interest in island biogeography has had an impact on conservation biology. Many features of island ecosystems are relevant to ecosystem conservation elsewhere, on land as well as in the oceans. Island ecosystems have helped our understanding of:- fragmentation (leading to insularization)
- creation of biotic communities, and
- species extinction.
| | Photo title: Acanthemblemaria mangognatha, a new tube blenny endemic to Islas Revillagigedos, Mexico | | Photo credit: D R Robertson | | | | |
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| Describing Ocean Life in Olden Days, Researchers Upend Modern Notions of Natural Animal Sizes, Abundance
Census of Marine Life Press Release 23 May 2009 | |
| | Before oil hunters in the 1800s harpooned whales by the score, the ocean between east Australia and New Zealand teemed with about 27,000 southern right whales – roughly 30 times as many as today – according to one of several astonishing reconstructions of ocean life in olden days to be presented at a Census of Marine Life conference in Vancouver, BC, Canada from May 26-28, 2009. At about the same time, pods of blue whales, 18-foot orca and thresher sharks darkened the waters off Cornwall, England. Blue sharks harassed fishermen along the coast, herds of 12-foot harbour porpoise pursued fish upriver, and dolphins regularly played in waters inshore. From such diverse sources as old ship logs, literary texts, tax accounts, newly translated legal documents and even mounted trophies, Census researchers are piecing together images – some flickering, others in high definition – of fish of such sizes, abundance and distribution in ages past that they stagger modern imaginations. | |
Read more at http://www.coml.org/node/282.
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