Page 158 - (DK) Ocean - The Definitive Visual Guide

156 SHALLOW SEAS

ATLANTIC OCEAN WEST BOILER REEFS ATLANTIC OCEAN WEST
These small reefs, close to the
Bermuda Platform surface, are called “boilers” after Lighthouse Reef
their frothy appearance when
TYPE Atoll with fringing waves break on them. TYPE Atoll with patch
and patch reefs reefs
AREA 150 square miles remains of corals and other AREA 120 square miles
(370 square km) organisms growing on the (300 square km)
CONDITION Some coral platform. Along the platform’s CONDITION Generally
bleaching reported southern and eastern edges, healthy
LOCATION Northwest Atlantic, extending west and limestone sand has gradually LOCATION Western Caribbean, 60 miles (80 km) east
north of the islands of Bermuda built up to form the of central Belize
Bermuda islands. Coral reefs
The Bermuda Platform is the elliptical, are present around the other Lighthouse Reef is an atoll lying
flattened summit of a huge volcanic edges of the platform, forming an Nevertheless, 21 different species 35 miles (55 km) east of the huge
submarine mountain (seamount) in atoll, while patch reefs grow on its of stony coral, 17 species of soft Belize barrier reef, off the coast
the northwest Atlantic. Its surface lies central surface. The diversity of reef (non-reef-building) coral, including of central Belize. It is roughly oval-
13–60 ft (4–18 m) below sea level and flora and fauna here is less than that many spectacular purple sea fans, shaped, about 23 miles (38 km) long,
is covered in a thick layer of limestone, associated with the reefs in the and about 120 different species of fish and 5 miles (8 km) wide on average.
formed over millions of years from the Caribbean Sea to the south. have been recorded here.

ATLANTIC OCEAN WEST over the past 35 years, mainly due to of algae has expanded. Causes of
human impact. Live coral cover has this degradation include overfishing,
Florida Reef Tract decreased, coral diseases have become fertilizer runoff from south Florida,
extensive, inhabitants that were once increase in ocean temperature and
TYPE Barrier reef, patch common (such as the queen conch) sea level, and sewage pollution from
reefs have virtually disappeared, and the boats. Other contributing factors
AREA 400 square miles area of reef encroached on by mats include hurricane damage, declines
(1,000 square km)
in algae-grazing
CONDITION Degraded; sea urchins, and
some recent recovery
direct damage
LOCATION From east of Soldier Key, Biscayne Bay, from dive-boat
to south of the Marquesas Keys, Florida, USA
anchors and ship
groundings. Steps
This system of coral reefs is 160 miles are being taken to
(260 km) long and curves to the east reverse the decline,
and south of the Florida Keys. Some with some signs
geologists classify it as a barrier reef, of success.
others as a barrier-like collection of
bank reefs. It is the largest area of CARYSFORT REEF
coral reefs in the US and has a high Carysfort Reef, part of
biodiversity, being home to more than the Florida Reef Tract,
40 species of stony coral, 500 species lies close to Key Largo
of fish, and hundreds of mollusk and is the site of many
species. The reefs’ health has declined ancient shipwrecks.

ATLANTIC OCEAN WEST The Bahamas is an archipelago of barrier reef near the island of Andros.
some 700 islands scattered over two The reefs are home to a range of
Bahama Banks limestone platforms, the Little Bahama corals and coral reef-dwelling animals
and Great Bahama Banks, in the West that is typical for the western tropical
TYPE Fringing reefs, Indies. The platforms have been Atlantic. Although local declines in
patch reefs, barrier reef
accumulating for at least 70 million coral cover and occasional outbreaks
AREA 1,200 square miles years—the Great Bahama Bank is over of coral disease have been recorded,
(3,150 square km)
15,000 ft (4,500 m) thick—yet their the reefs are generally healthy. There
CONDITION Localized surfaces remain 33–80 ft (10–25 m) has been concern about overgrowth of
areas of damage
below sea level. Many of the islands algae, but for now the algae are being
LOCATION Bahamas, southeast of Florida, US, and have fringing coral reefs; there are also kept in check by a thriving population
northeast of Cuba
many patch reefs on the Banks and a of parrotfish, which graze the reefs.

OCEAN ENVIRONMENTS HARD AND SOFT CORALS

This diverse group of corals, including a
large purple sea fan, was photographed
off the island of New Providence.