Recreational fishing expenditure as an indicator of coastal wetland habitat value

Valuing the ecosystem services provided by nature is essential for estuarine habitat conservation and restoration. Recreational fisheries rely on fish stocks that are dependent on productivity derived from the plants that comprise estuarine habitats, however the value of these habitats to recreational fishing is rarely considered. Here, we consider expenditure on recreational fishing activities as an indicator of coastal wetland habitat value, by synthesising data on routinely collected recreational effort, catch, and expenditure from telephone surveys alongside trophic subsidy models within a simple framework. The approach is demonstrated for the Clarence River and the Hunter River estuaries (New South Wales, Australia). Expenditure on recreational fishing activities was apportioned to mangrove and saltmarsh habitats via the ‘trophic subsidy’ (or nutrition) originating from primary producers in these habitats that fuels the biomass of important recreational species. The values estimated exceeded that of similarly apportioned commercial fisheries revenue, with the biggest difference observed for saltmarsh in the Clarence River (∼$17 million AUD per annum [recreational expenditure] compared to ∼$8 million AUD per annum [commercial fisheries total output]). When considered in an additive fashion and standardised by habitat extent, the values attributable to coastal wetland productivity were as high as $86 459 per hectare per annum for saltmarsh, and $20 611 per hectare per annum for mangroves. These values reflect the dependency of fisheries activities on the extent and condition of coastal wetland habitats, and the framework presented here is widely applicable for considering the economic value of these activities i.e., fishing) as an indicator of habitat value.