The worldwide costs of marine protected areas

Abstract

Declines in marine harvests, wildlife, and habitats have prompted calls at both the 2002 World Summit on Sustainable Development and the 2003 World Parks Congress for the establishment of a global system of marine protected areas (MPAs). MPAs that restrict fishing and other human activities conserve habitats and populations and, by exporting biomass, may sustain or increase yields of nearby fisheries. Here we provide an estimate of the costs of a global MPA network, based on a survey of the running costs of 83 MPAs worldwide. Annual running costs per unit area spanned six orders of magnitude, and were higher in MPAs that were smaller, closer to coasts, and in high-cost, developed countries. Models extrapolating these findings suggest that a global MPA network meeting the World Parks Congress target of conserving 20-30% of the world's seas might cost between 5 billion and 19 billion US dollars annually to run and would probably create around one million jobs. Although substantial, gross network costs are less than current government expenditures on harmful subsidies to industrial fisheries. They also ignore potential private gains from improved fisheries and tourism and are dwarfed by likely social gains from increasing the sustainability of fisheries and securing vital ecosystem services.

Fig. 1.

The total annual cost per unit area of running MPAs in relation to the number of people living within 50 km (a); distance from inhabited land (b); national PPP (c); per capita GNP (d); whether or not the MPA was wholly protected from fishing (e); and MPA size (f). The columns in e give means ± SE of log₁₀-transformed costs.

Fig. 2.

The total annual cost per unit area of running MPAs plotted against fitted cost, estimated from the three-term model described in Table 1.

Fig. 3.

Total estimated running costs of MPA systems covering 1–40% of the world's seas, according to four different models of system expansion. The shaded area denotes recent estimates of global subsidies to industrial fisheries (see text), whereas the vertical dashed lines show the MPA coverage recently recommended by the World Parks Congress. Model a, new MPAs randomly located, with no coalescence allowed; model b, new MPAs randomly located, but with all neighboring MPAs allowed to coalesce; model c, currently unprotected cells adjacent to already protected cells being 10% more likely than others to be picked for reservation, and with coalescence allowed; model d, as for model c, but with 50% greater likelihood of adjacent cells being picked.