1. Introduction
Although it is generally believed that the main cause of over-exploitation of fish stocks is commercialised fishing, artisanal fishing is increasingly believed to threaten coastal stocks [1]. The worst threat comes from explosive and cyanide fishing, but more common types of artisanal fishing, such as coastal push nets and beach seines are known to harm substrates and target juvenile fish [2] and [3], leading to serious stock declines and trophic shifts [4] and [5]. The danger of such trophic shifts, or ‘fishing down the marine food web’, identified by Pauly et al. [6] in temperate fisheries, has been demonstrated in tropical fisheries where a reduction in the stocks of piscivores and carnivores at the higher trophic levels serves as the first sign of over-fishing [4], [7], [8] and [9]. However, because coral reef fish ecology is extremely complicated [10] and data on fishers’ catch are scarce, it is not easy to track these trophic shifts, still less their causes and remedies.