Figure 1
From: Fish-seastar facilitation leads to algal forest restoration on protected rocky reefs
Conceptual model of trophic interactions and their effect on habitat state in Mediterranean rocky reefs.
(A) Interactions among the seastar M. glacialis, the ornate wrasse T. pavo, the sea urchins P. lividus and A. lixula and the algae Cystoseira spp. Dotted arrows indicate indirect interactions, whereas solid arrows indicate direct interactions. +/− symbols indicate positive or negative effect of the interaction on the species pointed by the arrow. In Ustica Island the interaction between fish and seastar (1) facilitates predation on sea urchins (2) by the seastar. Urchins are in turn strong grazers and are able to alter algal coverage (3). (B) Temporal trends in M. glacialis densities, sea urchin densities and habitat state in Ustica Island MPA. Red line: P. lividus. Black line: A. lixula. Blue bars: M. glacialis. Green line: algal coverage. Images in figure by F. Di Trapani and P. Gianguzza.
