A guide for planners and managers - IUCN

124 MARINE AND COASTAL
PROTECTED AREAS
Box I-11. Marine Valuation Methods
Market prices are often a poor guide to the real economic value of marine resources.
As well as the fact that many marine products have no market at all (for example products
which are used for subsistence purposes only, or services which cannot be bought and
sold such as beach protection or carbon sequestration), market prices often underestimate
their true worth (for example the aesthetic and cultural significance attached to marine
protected areas is far higher than the entry fees people pay to enter and use them, the
patent fees paid for the development of marine resource-based pharmaceutical or
industrial applications only represents a tiny proportion of the potential value of these
developments, a wide range of taxes and subsidies distort the prices of marine products
in many countries). It has become necessary to find alternative valuation methods which
are capable of capturing the full worth, and total economic value, associated with marine
ecosystems.
Many advances have been made in the economic valuation of marine goods and
services. This includes the use of costs saved as a proxy for the value of marine goods
(for example the valuation of coral rag in Mafia Island, Tanzania at US$ 140/tonne—the
price of the next best substitute building material, imported cement (Dulvy et al., 1995)),
or marine ecosystem services (for example valuation of the shoreline protection services
provided by coral reefs, coastal marshes and mangroves in the Seychelles at some US$
0.8 million a year in terms of the costs of their replacement with artificial groynes and
barriers (Emerton, 1997), or the US$ 0.3 million a year global warming-associated
damage avoided by carbon sequestration functions of Djibouti’s coral reefs (Asrat and
Emerton, 1998). Another way of calculating values is to look at the way in which marine
resources are associated with other production and consumption processes (for example
the beneficial effect of the Anolis lizard on agricultural production in the Antilles was
estimated terms of the value associated with its control of crop pests, for the whole
population worth a maximum of over US$ 450 million (Narain and Fisher, 1994)).
Where people do not pay to consume marine resources, or pay a price that is
obviously lower than total utility gained, travel cost methods provide a particularly
useful way of estimating values (for example the total tourist value associated with the
Great Barrier Reef Marine Park was estimated by looking at the travel, accommodation
and other costs incurred, some A$ 800 million a year (Craik, 1994)). Finally, economic
valuation may be based on people’s responses to hypothetical “what if” questions, carried
out regardless of any actual markets in marine goods or associated resources and
production processes (for example by the use of contingent valuation methods to assess
residents’ support for actions to conserve the Batangas Bay in the Philippines based on
their stated willingness to increase garbage collection and sewage treatment charges, or
to pay fees to maintain fisheries and coral reefs (Tejan and Ross, 1997)).
who wish to develop marine and coastal areas for tourism, settlement, industry and
mariculture, as well as all the ultimate consumers of marine products, often continue
to contribute to marine degradation through their economic activities. Even the very
people who are attracted by MPAs, most notably tour operators and their clients, may
contribute to marine degradation.