An ex ante ecological economic assessment of the benefits arising from marine protected areas designation in the UK

This paper presents an estimate of the benefits of the proposed designation of a network of marine conservation zones (MCZs) in English territorial and UK offshore waters. This ex ante analysis was undertaken as part of a cost-benefit evidence base to inform implementation of the proposed UK Marine and Coastal Access Bill. This Bill is part of an ambitious plan to designate and manage UK marine areas using an Ecosystems Approach. Benefits are measured in terms of anticipated increases in the value of ecosystem goods and services provisioned by MCZs relative to the counterfactual, i.e. no designation. The principal valuation and thus policy challenge is presented by the need to use benefits transfer in a context where biophysical provisioning functions are not well-developed, where there are gaps in the valuation literature related to temperate marine ecosystem goods and services, and where values (where available) are presented in aggregate terms. This paper develops and applies a methodology that first apportions these aggregate benefits across the diverse range of marine landscapes and habitats and then estimates the marginal benefit of protection. The value of benefits was calculated for three different configurations of MCZs under two different management regimes. We estimate a benefit range from designation of between £10.2 billion and £23.5 billion in present value terms, applying a 3.5% discount rate. The study questions the extent to which a defensible policy evidence base can be developed in the absence of primary valuation data and where benefit estimates are reported in aggregate terms.