Species-specific habitat distribution of coral reef fish assemblages in relation to habitat characteristics in an Okinawan coral reef

Abstract

SynopsisWe determined the species-specific habitat associations of coral reef fishes and environmental characteristics in an Okinawan coral reef in Japan. We focused on three families (Pomacentridae, Gobiidae and Labridae) and attempted to determine differences in habitat utilization. We selected six sites along the coast of Amitori Bay, from the entrance to the innermost part, in order to cover a wide range of habitat characteristics (exposed habitat, semi-exposed habitat and sheltered habitat). The species diversity of coral assemblages was greater at the exposed and semi-exposed habitats, whereas branching coral mostly covered the sheltered habitat. The environmental factors that determine the species-specific spatial association in fishes differed among families. Both biological characteristics (coral morphology and coral species diversity) and physical characteristics (water depth and wave exposure) affected the spatial association of pomacentrids and gobiids. In contrast, physical characteristics such as substrate complexity and water depth affected the species-specific spatial association of labrid species. Further study is needed to determine the ecological factors that regulate the species-specific habitat preference in Okinawan coral reefs.

The effectiveness of different meso-scale rugosity metrics for predicting intra-habitat variation in coral-reef fish assemblages

“…Consequently, determining whether each of these aspects contributes equally to the abundances of different fish species is problematic. Similar problems occur when using maximum relief within a sampling unit (Wilson et al 2007;Harborne et al 2008b), statistics calculated from profile gauges (McCormick 1994), or metrics of change of height within quadrats (Nanami et al 2005).…”

Climate change impedes scleractinian corals as primary reef ecosystem engineers

“…High reef rugosity, for example where large massive Porites coral colonies dominate the seascape, is associated with high abundances of reef fishes (McClanahan and Shafir 1990). Similarly, a high abundance of microstructures within coral colonies is strongly and positively correlated with high fish and invertebrate diversity (Nanami and Nishihira 2004;Nanami et al 2005). Reduction in rugosity reduces the availability of habitat space at a variety of scales and leads to a considerable reduction in reef biodiversity (McClanahan and Shafir 1990).…”

Habitat use patterns of fishes across the mangrove-seagrass-coral reef seascape at Ishigaki Island, southern Japan

“…To detect potential ontogenetic habitat shifts for any fishes, which would then lead to the identification of the nursery habitats within a coastal area, a cross-shelf study across a variety of habitats is crucially important. Although a number of studies have been undertaken on fish assemblage structures in the Ryukyu Islands, almost all of these have been restricted to a single habitat type, such as mangroves (Shokita et al 1988;Tachihara et al 2003), seagrass beds (Kanashiro et al 1997;Nakamura and Sano 2004a;Horinouchi et al 2005a), macroalgal beds (Sano 2001), and coral areas (e.g., Shibuno et al 1999;Sano 2000;Lecchini et al 2003;Nanami et al 2005). Nakamura and Sano (2004b) was the only study in which fish comparisons were made among multiple habitats (seagrass bed, coral area, and sand area).…”