Variation in diet composition of the mudskipper, Periophthalmodon septemradiatus, from Hau River, Vietnam

Abstract

Periophthalmodon septemradiatus (Hamilton, 1822) is a mudskipper of the Mekong Delta. It can be found along estuaries and lower reaches of rivers. We determined diet and feeding ecology of this species by analyzing the contents within the stomachs of 1360 fish samples collected from August 2017 to July 2018. Data analysis suggests that P. septemradiatus is a carnivorous fish. We found six main food item categories: small fish, prawns (Acetes spp.), crabs (Uca spp.), mollusks, ants (Dolichoderus sp.), and detritus. Both males and females at different sizes, seasons, and habitats ingest primarily Dolichoderus sp., secondarily detritus, and rarely other prey. Diet composition is similar between sexes but varies according to fish size, season, and habitat. Dolichoderus sp. and detritus regulate the spatial variation of food composition. Our findings contribute to future artificial cultivation for conservation.

Foraging ecology of the amphibious mudskipper Periophthalmus chrysospilos (Gobiiformes: Gobiidae)

“…Biovolume of prey was calculated by the following equation: % V i = (100 × O i × Wi )/Σ(O i × W i ), where V i , O i and W i are the percentage of biovolume, occurrence and weight of prey i respectively. The diet composition was analysed against sex, size, site, and season to understand the interactions of these parameters to food acquisition ( Natarajan & Jhingran, 1961 ; Hyslop, 1980 ; Clayton, 2017 ; Dinh et al, 2020b ).…”

“…Fishes, occupying all trophic levels within aquatic environments, are integral components to elucidate aquatic trophic ecology ( Wootton, 1996 ; Blaber, 2000 ). In intertidal systems where terrestrial elements factor significantly in trophic ecology, studies traditionally focus on the impact of the environment on the foraging strategy of fishes ( Ravi, 2013 ; Tran, Hoang & Dinh, 2019 ; Dinh et al, 2020b ). During the ebb tide, the landscape of intertidal areas changes drastically.…”

“…Some species, such as those from the genus Boleophthalmus , are less tolerant to desiccation, stay close to the waterline, and graze the substrate surface for diatoms ( Ravi, 2013 ; Dinh, 2015 ). Others, such as species of Periophthalmodon , are carnivorous and are known to traverse upriver to areas unaffected by tidal cycles ( Dinh, 2018a , 2018b ; Dinh, Tran & Nguyen, 2018 ; Dinh et al, 2020b ).…”

“…The prominence of these mesopredators within the intertidal zone, makes species of Periophthalmus excellent candidates to understand the energetic connectivity between terrestrial and aquatic systems. Yet, current information on the effects of spatio-temporal factors on the diet and foraging ecology of these fishes remain scarce ( Ravi, 2013 ; Tran, Hoang & Dinh, 2019 ; Dinh et al, 2020b ). We study the diet composition of an obligate intertidal species, Periophthalmus chrysospilos Bleeker 1853 (Gobiidae: Oxudercinae).…”

Burrow structure and utilization in the mudskipper Periophthalmodon septemradiatus from the Mekong Delta

“…Particularly, the species in the Mekong River basin was found to be a multiple spawner and live from estuary to the upper reaches of river system (Dinh et al ., 2020; Mai et al ., 2019). This species is a carnivore (Dinh et al ., 2018 a ; Dinh et al ., 2020) who feeds mainly on ants, shrimps and small fishes (Dinh et al ., 2020). The species’ morphometric and meristic measurements vary from the lower to upper reaches of river system (Dinh et al ., 2018 b ).…”