Chapter I Intro & Objectives - SPREP

PHOENIX ISLANDS PROTECTED AREA MANAGEMENT PLAN
Chapter III. Background, 1. Physical Setting of the Islands
Draft 1 March 2007
CHAPTER III.
BACKGROUND
1. PHYSICAL SETTING OF THE ISLANDS
A. GEOLOGICAL
Zimmerman (1947) noted that there was a definite cycle of geological metamorphosis that is
illustrated by atolls such as the Phoenix Islands. Systematic deep core boring of atolls was
suggested as a priority area in the study of atolls. Zimmerman (1947) speculated that many
atolls including the Phoenix Islands may have been high islands in the past with more
complex species communities.
Table III-1.1. Key physical features and vegetation of the Phoenix Islands
(source: Pierce et al 2006)
Island Total Land Lagoon Substrate Vegetation
area (ha) area (ha)
Manra - c.500 Closed Not visited Forest, scrub,
coconut
Rawaki 73.24 58.14 Closed Rubble, c.50% sand Grass, low scrub
Enderbury 596.6 500+ Closed Rubble, extensive
sand
Grass, low scrub
Birnie 50.95 48.2 Closed Rubble, limited sand Grass, low scrub
Kanton - c.900 Open Varied, extensive Forest, scrub,
sand
coconut
McKean 74.32 48.77 Closed Rubble, < 30% sand Grass, low scrub
Orona - c.600 Open Rubble, sand Forest, scrub,
coconut
Nikumaroro - c.400 Open Rubble, sand Forest, scrub,
coconut
Note: Land areas are total atoll area minus lagoon area; Rawaki, McKean and Birnie data courtesy of T.
Conaghan, NZ Department of Conservation, others from Garnett (1983). Note that some land area estimates are
significantly greater than previously reported, notably Birnie (48.2 ha, c.f. 20 ha in Garnett 1983).
ABARIRINGA (CANTON, KANTON)
Dimensions - Abariringa is the largest coral atoll in the Phoenix Islands (Hydrographic Office
1940). It is 7.2 km (4.5 miles) wide on the west and 14.5 km (9 miles) from the northern
point to the southeastern point (Bryan 1941 and 1942). It is shaped like a pork chop.
The maximum island height is 6.1 m (20 ft) (Hydrographic Office 1940; see also
Hydrographer of the Navy 1969). The width of the land is between 91 to 457 m (100 to 500
yards) (Hydrographic Office 1940; 46 to 549 m (50 to 600 yards) according to Bryan 1941
and 1942; not wider than 975 m (3,200 ft) according to Hatheway 1955). The beach is
composed of coral sand or broken fragments of reef rock (Bryan 1941 and 1942). The beach
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