Study site
We quantified changes in fish assemblages within the Solitary Islands region in New South Wales, eastern Australia (Supplementary Figure 1). Previously, Vergés et al. (2016) showed that kelp disappeared from multiple mid-shelf reefs (<6km offshore) reefs after 2009. These reefs support mixed communities of tropical, subtropical and temperate fish (Malcolm et al. 2010), and over the last decade have experienced gradual warming (Vergés et al. 2016). In particular, we analysed the fish community at 5 individual reefs spanning ~20km of coast; Jeffrey Shoal (-30.24913, 153.1993), Sawtell Reef (-30.36616, 153.13127), Split Bommie North (-30.24125, 153.20163), Split Bommie West (-30.24071, 153.19235) and Whitmore (-30.34795, 153.13901) (SI. Fig. 1). Three of these sites (Jeffrey Shoal, Split Bommie North and Split Bommie West) are located inside the Solitary Islands Marine Park, which was established in 1998 with existing management rules commencing in 2002. These three study sites are within Habitat Protection Zones, where recreational fishing and some types of commercial fishing (e.g. line fishing) are allowed. The other two sites (Sawtell and Whitmore) are outside the Solitary Islands Marine Park and managed under general fishing regulations (e.g. with bag and size limits).