Page 163 - (DK) Ocean - The Definitive Visual Guide

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PACIFIC OCEAN SOUTHWEST
Great Barrier Reef

TYPE Barrier reef
AREA 37,000 square km
(14,300 square miles)
CONDITION Damaged by
tropical storms, pollution,
and an unbalanced
ecosystem
LOCATION Parallel to Queensland coast,
northeastern Australia

Australia’s Great Barrier Reef, which
stretches 2,010km (1,250 miles), is
the world’s largest coral reef system.
Often described as the largest structure REEF CHANNEL
ever made by living organisms, it in In this view of a central area of the reef, THE WORLD’S SMALLEST VERTEBRATE?
fact consists of some 3,000 individual a deep, meandering channel separates two
reefs and small coral islands. Its outer reef platforms. The region’s high tidal range One of the tiniest residents of the
edge ranges from 30 to 250km (18 to drives strong currents through such channels. Great Barrier Reef, at just
1
155 miles) from the mainland, and its 7–8mm (less than ⁄3in) long from
biological diversity is high. The reef However, a study published in 2012 snout to tail, is the Stout Infantfish.
contains about 350 species of stony reported that the reef has lost more When discovered in 2004, the
coral and many of soft coral. Its 1,500 than half its coral cover since 1985. Infantfish was declared to be the
species of fish range from 45 species of The factors causing this damage world’s smallest vertebrate species. That
butterflyfish, to several shark species, include pollution, tropical cyclones, title has since been claimed first by a slightly
including silvertip, hammerhead, and raised water temperature causing mass smaller species of Indonesian cyprinid fish, and
whale sharks. The reef is also home to coral bleaching, population outbreaks more recently by a tiny species of frog, about
1
500 species of algae, 20 species of sea of the Crown-of-thorns Starfish, 7mm ( ⁄4in) long, found in Papua New Guinea.
snake, and 4,000 species of mollusc. overfishing, and shipping accidents.

PACIFIC OCEAN SOUTHWEST The Marshall Islands consist of 29 PACIFIC OCEAN SOUTHWEST recorded. The reefs’ health is generally
coral atolls and five small islands in good, but some reefs around the busy
Marshall Islands the western Pacific. The atolls lie on Society Islands holiday destination islands of Tahiti,
top of ancient volcanic peaks that are Moorea, and Bora-Bora have been
TYPE Atolls thought to have erupted from the TYPE Fringing reefs, severely affected by construction,
AREA 6,200 square km ocean floor 50-60 million years ago. barrier reefs, atolls sewage, and sediment run-off.
(2,400 square miles) They include Kwajalein, the largest AREA 1,500 square km
CONDITION Generally atoll in the Pacific at 2,500 square km (600 square miles)
good; some episodes (1,000 square miles), and Bikini and CONDITION Good, but
of coral bleaching Enewetak atolls, which were used by significant local damage
LOCATION Micronesia, southwest of Hawaii, the USA for testing nuclear weapons LOCATION French Polynesia, northeast of New
western Pacific between 1946 and 1962. Human Zealand, south-central Pacific
pressures on these two
remote, evacuated atolls have The Society Islands comprise a chain
been minimal during the of volcanic and coral islands in the
past 50 years, and marine life South Pacific, including islands with
around them now thrives; for barrier reefs (such as Rai’atea), islands
example, 250 species of coral with both fringing and barrier reefs
and up to 1,000 species of fish (such as Tahiti), and atolls or near-
have been recorded at Bikini. atolls (such as Maupihaa and Maupiti).
The reefs’ biological diversity is
MAJURO ATOLL moderate compared with the reefs
As with many Pacific atolls, the rim of Southeast Asia, although more than MOOREA
of Majuro Atoll consists partly of 160 coral species, 800 species of reef A wide fringing reef almost completely
shallow submerged reef and partly fish, 1,000 species of mollusc, and surrounds the shoreline of mountainous
of small, low-lying islands. 30 species of echinoderm have been Moorea, part of which is visible in this view.

PACIFIC OCEAN CENTRAL northwest over a hotspot in the Earth’s FRENCH FRIGATE SHOALS
mantle. Coral reefs fringe some coastal Reef fish, including Longfin Bannerfish,
Hawaiian areas of the younger, substantial islands Milletseed Butterflyfish, and
at the southeastern end of the chain, Bluestripe Snappers,
Archipelago such as Oahu and Molokai. To the swim around
northwest, located on the submerged a table coral.
TYPE Fringing reefs,
atolls, submerged reefs summits of older, sunken islands, are
several near-atolls (such as the French
AREA 1,180 square km
(450 square miles) Frigate Shoals) and atolls (such as
Midway Atoll). These reefs are highly
CONDITION Coral disease OCEAN ENVIRONMENTS
outbreaks reported isolated from all other coral reefs
in the world, and although their
LOCATION North-central Pacific
overall biological diversity is
relatively low, many new species
The Hawaiian Archipelago consists of have evolved on them. The
the exposed peaks of a huge undersea more remote reefs are healthy,
mountain range. These mountains have but in 2013, a serious coral
formed over tens of millions disease was reported affecting
of years as the Pacific Plate moves reefs on Oahu and Kauai.