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PATTERNS OF LOSS ACROSS ISLAND TAXA 305

forests in which deforestation has been concentrated,
hence over half of the Philippines’ 184 endemic birds
are considered threatened.
How these various assessments of risk translate
into future patterns of loss will depend on a variety
of factors; not least, the protection afforded to par-
ticular island habitats and species, and conflicting
economic pressures on the resource base of particu-
lar islands. It is one thing to identify causes of
species extinction, quite another to provide reme-
dies. Solutions to the problems demand political
will, legislation, finance, education, and broad pub-
lic support (Chapter 12). Nonetheless, the first step
is to assess and articulate the problem.

11.6 A record of passage—patterns of loss across island taxa

To set the following sections in context, it is worth
noting variations in the timing of human settlement

(Table 11.5). When Europeans began their major

phase of expanding around the world from the six-

teenth century onwards, they encountered islands

with varying antiquity of human occupation. We

might arbitrarily distinguish three groups: (1)

palaeoinhabited islands, which were populated

several millennia or tens of millennia before

European expansion (e.g. New Guinea, the

Solomons, Tasmania, the Antilles); (2) neoinhabited

islands, which were populated just one or two mil-

lennia before European contact (e.g. the Canaries,

Madagascar, Marquesas, Hawaii, New Zealand),

and finally, (3) previously uninhabited islands, still

pristine when the European expansion began (e.g.

the Azores, Madeira, Cape Verde, St Helena,

Tristan, Mascarenes, Galápagos, Juan Fernández).

The record of species extinctions from the islands

that were colonized before modern European con-

tact is largely dependent on proxy sources.

Important techniques include the analysis of pollen

(a) Most threatened (b) All

Arid

1%

Unknown

2%

Seasonal/

temperate

forest

25%

Small

islands

6%

Inland or

coastal

water

10%

Grassland,

heathland

or scrub

12%

Rain forest

44%

Grassland,
heathland
or scrub
13%

Inland or

coastal

water

10%

Small

islands

9%

Seasonal/

temperate

forest

36%

Rain forest

32%

Figure 11.3Habitats of threatened island endemic bird species: (a) species listed as either endangered or vulnerable, (b) species listed as
endangered, vulnerable, rare, indeterminate, or insufficiently known. Some species have been assigned to more than one habitat in this analysis,
hence, for example, the relative importance of the combined forest habitat in part (b) (69%) differs slightly from the estimate for forest species
(77%) given in the text. Data from Johnson and Stattersfield (1990), according to the then IUCN Red Data Bookcategories:endangered—those in
danger of extinction and whose survival is unlikely if the causal factors continue operating;vulnerable—those likely to move into the endangered
category in the near future;rare—taxa with small world populations;indeterminate—taxa known to belong to one of the foregoing categories,
but with insufficient data to say which;insufficiently known—taxa suspected but not definitely known to belong to one of the foregoing
categories. (The data given in this figure exclude the category extinct—taxa no longer known to exist in the wild after repeated searches of their
type localities.)