Ontogenetic changes in the diet of the herbivorous Scartichthys viridis in a rocky intertidal zone in central Chile

Abstract

Scartichthys viridis maintains a herbivorous diet following recruitment to rocky intertidal areas, where it consumes almost exclusively macroalgae. The sheet-like green macroalgae Ulva and Enteromorpha were the main items consumed by individuals <130 mm L T . The tough branching red macroalga Gelidium made the bulk of the gut contents of specimens >220 mm L T , Ulva being consumed to a much lesser extent. Further, Gelidium increased in importance in the total gut contents during ontogeny. In contrast, both small (70-120 mm L T ) and medium-sized (140-210 mm L T ) S. viridis individuals preferred Ulva in the laboratory. It is suggested that the increasing consumption of Gelidium along the ontogeny of S. viridis results from the limited availability of Ulva in the field. Large S. viridis individuals possessed longer guts relative to their body length, in comparison with small individuals. 2000 The Fisheries Society of the British Isles

Effects of predation and habitat structure on the abundance and population structure of the rock shrimp Rhynchocinetes typus (Caridea) on temperate rocky reefs

“…The actual intensity of predation may have been overestimated by opportunistic attacks of the groups of S. viridis (Blenniidae), a fish species commonly considered to be an herbivore (Muñoz and Ojeda 2000). However, densities of S. viridis were similar among all six sites, suggesting that the much higher predation at MA1 cannot solely be attributable to the presence of this blenny.…”

Coastal fish assemblages and predation pressure in northern-central Chilean Lessonia trabeculata kelp forests and barren grounds

“…Scartichthys viridis/gigas was the species that consumed the most prey during video recordings. This species has originally been described as an herbivorous species with more than 90% of their stomach contents comprising seaweeds, mostly chlorophytes and rhodophytes (Ojeda & Muñoz, 1999; Muñoz & Ojeda, 2000). However, those studies were conducted on individuals from the intertidal zone, with little information on the foraging behaviour of this species in subtidal habitats.…”

Trophic relationships in tidepool fish assemblages of the tropical Southwestern Atlantic

“…At Castelhanos inter-tidal reef, the trophic structure of assemblages is built upon convergence toward food items partitioned within feeding guilds by inter-specific differences in consumer size, microhabitat, behavior and trophic specialization. However, ontogenetic changes in diet, such as in omnivorous species shifting to herbivory in adulthood, also lead to changes in trophic guilds throughout life (Muñoz & Ojeda, 1998, 2000 and induce temporal variations at both guild and community structure levels (Wilson & Sheaves, 2001). In this respect, stable isotope and fatty acid analyses are promising approaches to characterize complex trophic interactions and define trophic niches (Hielscher et al, 2015) through the integration of spatial and temporal information of the trophic relationships within communities (Nagata et al, 2015).…”

“…Moreover, studies on diet and trophic ecology of tropical intertidal fishes (Castellanos-Galindo & Giraldo, 2008; Kotrschal & Thomson, 1986;Zamprogno, 1989) are incipient when compared to tropical subtidal fishes (Dubiaski-Silva & Masunari, 2008;Ferreira & Gonçalves, 2006;Ferreira, Floeter, Gasparini, Ferreira, & Joyeux, 2004;Ferreira, Gonçalves, Coutinho, & Peret, 1998;Randall, 1967) or temperate inter-tidal fishes (Grossman, 1986;Hielscher, Malzahn, Diekmann, & Aberle, 2015;Muñoz & Ojeda, 1997, 2000Velasco et al, 2010). The inter-tidal reef of Castelhanos beach, in the tropical Southwestern Atlantic, has a carbonate substrate and undergoes complete submersion at high tide (Macieira & Joyeux, 2011).…”