Linking Mesohabitat Selection and Ecological Traits of a Fish Assemblage in a Small Tropical Stream (Tinggi River, Pahang Basin) of the Malay Peninsula

Abstract

Mesohabitat selection in fluvial fishes was studied in a small tropical stream of the Malay Peninsula. A total of 681 individuals representing 24 species were sampled at 45 stations within heterogeneous stream (ca. 1 km in length), in which water depth, water velocity, substrate size, and riparian canopy cover were measured as environmental variables. A canonical correspondence analysis (CCA) yielded a diagram that shows a specific mesohabitat selection of the fish assemblage, in which the species were plotted widely on the CCA1-CCA2 biplot. Generalized linear model also revealed a significant pattern of the mesohabitat selection of several species. Water velocity and substrate size mainly separated on CCA1, indicating variation of pool (deep, slow-flow section) and riffle (shallow, fast-flow section) structures is a primary factor of mesohabitat selection in the fluvial fish assemblage. The mean body weight of species significantly correlated with CCA1; larger species tended to inhabit pools, while small ones occupied riffles. The riparian canopy cover separated on CCA2. The trophic level of species significantly correlated with CCA2; herbivorous species (low trophic level) selected open sites without riparian cover, whereas omnivorous/carnivorous (middle-high trophic level) species preferred highly covered sites. In conclusion, our results suggest that mesohabitat selection is closely related to the species feeding habit, which is consistent with the results of previous studies.

Microhabitat segregation and fine ecomorphological dissimilarity between two closely phylogenetically related grazer fishes in an Atlantic Forest stream, Brazil

“…This form-function relationship makes ecomorphological analysis a reliable methodology to infer many aspects of fish's niche, such as ecological interactions and habitat preferences (Gatz 1979a;Winemiller 1991;Langerhans et al 2003;Casatti and Castro 2006;Leal et al 2010). However, most studies relating morphology and spatial distribution of fishes in streams and rivers have defined the space in physiognomically homogeneous units (i.e., mesohabitat scale, such as riffles, runs, and pools; Rezende et al 2010;Kano et al 2013). Consequently, they probably have not detected niche segregation among several closely related species or morphological types, which in fact tend to occupy similar mesohabitats (e.g., riffles predominately occupied by depressed-body species, whereas pools inhabited by deep-body ones).…”

Ichthyofaunal assessment of the Gelami and Tinggi Rivers, Pahang River System, eastern Malay Peninsula, following construction of an adjacent building complex

“…Three "R" (rare: species usually localized within restricted geographical areas or habitats, or thinly scattered over a more extensive range) or "EN" (endangered: species facing a very high risk of extinction in the wild in the near future) species were not recorded in the most recent survey (Table 1), although several species noted by Othman et al (2003) as "not common" (NC) were represented by many individuals (Kano et al 2013b). It is clear that future habitat conservation and maintenance of fish diversity levels will necessitate continuous quantitative monitoring (see Kano et al 2013b). Othman et al (2003) and the present survey.…”

Homogenization of Fish Composition Among Mesohabitats Driven by Stream Degradation from Urban Land Use

“…Studies have shown that these distinct characteristics of mesohabitats can select sh species according to their ecological requirements (e.g. diet, reproductive strategies, and substrate preference) (Berkman and Rabeni 1987; Teresa and Casatti 2012; Kano et al 2013) and body morphology (Gaston et al 2012;Bower and Piller 2015;Lujan and Conway 2015). For example, species that present a dorsoventrally depressed body are commonly found in the ri es, while the laterally compressed body is a prevalent characteristic of the species that inhabit the pools (Gaston et al 2012).…”