Community structure of small fishes in a shallow macrophytic lake (Niushan Lake) along the middle reach of the Yangtze River, China

Abstract

-This study describes the current status of the small fish community in Niushan Lake in China, and examines the spatial and seasonal variations of the community in relation to key environmental factors. Based on macrophyte cover conditions, the lake was divided into three major habitat types: (1) Potamogeton maackianus habitat, (2) Potamogeton maackianus and Myriophyllum spicatum habitat, and (3) uncovered or less-covered habitat. Fish were sampled quantitatively in the three habitat types by block nets seasonally from September 2002 to August 2003. A total of 10 469 individuals from 27 fish species were caught, among which 20 species were considered as small fishes. Rhodeus ocellatus, Paracheilognathus imberbis, Pseudorasbora parva, Micropercops swinhonis and Cultrichthys erythropterus were recognized as dominant small fishes according to their abundance and occurrence. It was noted that (1) small fishes predominated the total number of fish species in the lake, which reflected to some degree the size diminution phenomenon of fish resources; (2) many small fishes had plant detritus as their food item, which was consistent with the abundance of macrophyte detritus in the lake and implied the importance of detritus in supporting small fish secondary production. Canonical correspondence analysis suggested that the spatial distributions of most small fishes were associated with complex macrophyte cover conditions. Macrophyte biomass was positively correlated with species richness, diversity index and the catch per unit of effort (CPUE) of the fish community. Water depth had no significant effects on species diversity and distribution of the small fishes. Correspondence analysis revealed a higher occurrence of the small fishes and higher abundance of individuals in summer and autumn. Seasonal length-frequency distributions of several species indicated that more larval and juvenile individuals appeared in spring and summer. This study provides some baseline information which will be essential to long-term monitoring of small fish communities in the Yangtze lakes.Key words: Small fishes / Freshwater community structure / Habitat utilization / Multivariate statistics / Lake fishery management / Yangtze lakes Résumé -Structure de la communauté des poissons de petites tailles du lac Niushan connecté au fleuve Yangtze (Chine). Ce travail décrit l'état actuel de la communauté des poissons du lac Niushan (Chine) en examinant la distribution spatiale et les variations saisonnières de la communauté en relation avec les principaux facteurs environnementaux du milieu. Les différentes espèces de macrophytes permettent de diviser les habitats du lac en 3 types : (1) habitat à Potamogeton maackianus, (2) habitat à Potamogeton maackianus et Myriophyllum spicatum, et (3) habitat sans ou peu de macrophyte. Les échantillonnages des poissons des trois types habitats ont été effectués à différentes saisons, de septembre 2002 à août 2003. Au total, 10 469 individus appartenant à 27 espèces de poissons ont été pêchés ; 20 espèces...

Effects of a small planktivore (Pseudorasbora parva: Cyprinidae) on eutrophication of a shallow eutrophic lake in central China

“…Pseudorasbora parva is a small planktivore and feeds mainly on aquatic insects, algae, and zooplankton Xie et al, 2000;Yang et al, 2004). This fish species is extremely abundant and plays an important role in fish communities in shallow lakes along the middle reach of the Yangtze River , Xie et al, 2001Xie et al, 2005;Ye et al, 2006). However, we found no study documenting the effects of P. parva on eutrophication in shallow lakes.…”

Abundance and spatial variability of invasive fishes related to environmental factors in a eutrophic Yunnan Plateau lake, Lake Dianchi, southwestern China

“…A lot of empirical studies undertaken in temperate and subtropical lakes have shown that macrophytes offer fish increased foraging opportunities, reduced predation risk, and suitable spawning sites (Dibble et al 1996). Our previous studies in the shallows Yangtze lakes found that the spatial distributions of many fishes are positively associated with submerged macrophytes due to the benefits provided by macrophyte cover (Ye et al 2006). Our research in Lake Erhai, the second largest lake in the Yunnan Plateau, also indicated that the majority of fish species in the lake preferred habitats with abundant macrophytes (Tang et al 2013).…”

“…only listed as introduced fish species without any abundance description by Yang (1996)], and thus assessments of their ecological impacts on local fish community and ecosystem function are unavailable so far. This situation existed partly because these noncommercial species are not targeted by the artisan fisheries of Lake Dianchi and fishery-dependent sampling on the scale that is needed to truly understand fish distribution is costly and usually was given low priority Biol Fish (2015) 98:209-224in lake management (Ye et al 2006). In this light, our experimental sampling with the multiple mesh-sized gillnets can provide an alternative method to evaluate population status of these non-commercial small fish species as well as monitor their long-term dynamics.…”

Predicting fish species richness and assemblages with climatic, geographic and morphometric factors: A broad-scale study in Chinese lakes

“…Specifically, depended on varied study scales, completely different driving factors were emphasized. For instance in local studies, surface area, water depth, water quality (dissolved oxygen, total phosphorus, total nitrogen, chlorophyll a, transparency), habitat type and relative organisms (fish, zooplankton, phytoplankton and macrophtye) were sometimes over-emphasized as potential factors linked to fish species richness and assemblages (Mehner et al, 2005;Ye et al, 2006;Cheng et al, 2012). But climatic factors (e.g.…”

“…Over the last several decades, on-going efforts have been studying fish and fisheries in Chinese lakes. Most studies focused on fish biology, fish community and fish stock enhancement in single or a few lakes in local area (Xie et al, 2001;Ye et al, 2006;Cheng et al, 2010). However, due to the difficulties in compiling reliable and large database of fish species in Chinese lakes, there has been surprisingly little effort to investigate lake fish assemblages related to multiple environmental factors in large spatial scale up until now .…”