Impacts of habitat protection on trophic ecology of white-spotted rabbitfish, Siganus sutor (Valenciennes 1835)

Abstract

This study examined how habitat protection influences the feeding behavior and overall health of rabbit fish Siganus sutor, an important species in artisanal fisheries in coastal Kenya. Total length (cm) and weight (g) of 75 specimens landed by fishers in protected (Kiunga, Ishakani) and unprotected areas (Faza, Kizingitini) were measured, and used to assess length-weight ratios and the overall health condition of specimens.  Stomach contents were evaluated for feeding intensity, frequency of occurrence, diversity and relative abundance of food items.  Protected areas exhibited significantly higher diversity in stomach contents, forming distinct trophic guilds.  Habitat protection influenced fish feeding strategies, with unprotected sites showing signs of food deprivation and probable facultative detritivory. Ontogenic feeding variations were evident, with fish size affecting dietary diversity. A Principal Component Analysis grouped the four sites into two major categories: protected (Kiunga and Ishakani) and unprotected (Faza and Kizingitini) based on fish health condition, food item diversity, and relative abundance. These findings suggest that habitat protection shapes the feeding ecology of S. sutor. A longer time series study of spillover effects of Kiunga Marine Reserve would inform policies and regulations for fish habitat protection measures and managing adjacent fisheries.