Rhinogobius Giurinus Research Articles

Length-weight relationships for four small fish species caught in wetlands of central Yangtze River, China

Summary Length–weight relationships for four native species (Oryzias latipes Temminck & Schlegel, 1846; Rhodeus ocellatus Kner, 1866; Rhinogobius giurinus Rutter, 1897; and Micropercops swinhonis Gunther, 1873) were determined. The fish were collected from the wetlands of the central Yangtze River, in Wuhan, Hubei Province, China. Samples were obtained from May 2012 to January 2013. Length–weight relationships for O. latipes were determined for the first time.

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

Lake Dianchi is the largest freshwater lake on the Yunnan Plateau and the sixth largest one in China. In recent decades, a number of non-native fish species have been introduced into the lake intentionally or accidentally while human-accelerated eutrophication has been occurring. In this study, we provided a whole-lake assessment of species composition and abundance of the accidentally-introduced fishes, and described the spatial variability of invasive small fish community in relation to eight physicochemical environmental factors. Fish were sampled quantitatively at 30 sites throughout the lake with multiple mesh-sized gillnets in the autumn of 2008. A total of 2,050 individuals from seven non-native small fish species were captured. Thin sharpbelly Toxabramis swinhonis and piper halfbeak Hyporhamphus intermedius were recognized as dominant species, followed by barcheek goby Rhinogobius giurinus, topmouth gudgeon Pseudorasbora parva and redfin culter Culterichthys erythropterus, according to their abundance and occurrence. Principal component analysis (PCA) suggested that the fish community structure in the northern part was distinct from those in the middle and southern parts of the lake, corresponding to the increase of lake eutrophic level from south to north. Redundancy analysis (RDA) showed that redfin culter, piper halfbeak and thin sharpbelly were positively related to nutrient variables (total phosphorus, total nitrogen), while topmouth gudgeon and barcheek goby were associated with relatively higher secchi depth and lower nutrition level. Water depth seemed to have moderately negative influence on spatial distribution of all the fish species. Regression tree analysis was applied to visualize decision rules for the prediction of fish abundances (CPUE, ind/fishing pass/h) from key environment variables, and explained 51.5-69.0 % of the total variance of response values. The details of these findings are beneficial to understanding the establishment of invasive fish in degraded environment, and to developing suitable conservation strategies for the restoration and management of fish resources in Lake Dianchi as well as the other lakes of Yunnan Plateau.

Freshwater fish species richness and conservation of mountain streams in the Jinggangshan National Nature Reserve, China

Jinggangshan National Nature Reserve is located in the middle reach of the Luoxiao Mountains in the south-western Jiangxi Province. The fish fauna of mountain streams in the nature reserve was investigated seasonally during 2011. A total of 553 samples were collected and classified into 12 families and 38 species. The samples collected in the nature reserve did not include any exotic species. The most abundant fish species collected was Pseudogastromyzon changtingensis tungpeiensis, followed by Acrossocheilus parallens, Rhinogobius cliffordpopei and Rhinogobius giurinus. A total of 16 species were found to be endemic to China. Current threats to the conservation of fishes in the nature reserve were reviewed and management solutions were suggested.

Complete mitochondrial genome of Rhinogobius giurinus (Perciformes: Gobiidae: Gobionellinae)

In this study, we present the complete mitochondrial gene for the freshwater goby Rhinogobius giurinus. The genome is a circular molecule of 16,520 bp in length and consists of 13 protein-coding genes, 22 tRNA genes, 2 ribosomal RNA genes and 2 main non-coding regions (the control region and the origin of the light strand replication). The overall base composition of R. giurinus is 26.08% for T, 29.56% for C, 27.73% for A and 16.63% for G, with a slight A + T bias of 53.81%. It has the typical vertebrate mitochondrial gene arrangement.

Status and historical changes in the fish community in Erhai Lake

Erhai Lake is the second largest freshwater lake on the Yunnan Plateau, Southwest China. In recent decades, a number of exotic fish species have been introduced into the lake and the fish community has changed considerably. We evaluated the status of the fish community based on surveys with multimesh gillnet, trap net, and benthic fyke-net between May 2009 and April 2012. In addition, we evaluated the change in the community using historical data (1952–2010) describing the fish community and fishery harvest. The current fish community is dominated by small-sized fishes, including Pseudorasbora parva, Rhinogobius giurinus, Micropercops swinhonis, Hemiculter leucisculus, and Rhinogobius cliffordpopei. These accounted for 87.7% of the 22 546 total specimens collected. Omnivorous and carnivorous species dominated the community. A canonical correspondence analysis (CCA) plot revealed that the distribution of fishes in the lake is influenced by aquatic plants, water temperature, pH, and season. The abundance of indigenous species has declined sharply, and a majority of endemic species have been extirpated from the lake (a decrease from seven to two species). In contrast, the number of exotic species has increased since the 1960s to a total of 22 at present. The fishery harvest decreased initially following the 1960s, but has since increased due to the introduction of non-native fish and stocking of native fish. The fishery harvest was significantly correlated with total nitrogen, not total phosphorus, during the past 20 years. Based on our results, we discuss recommendations for the restoration and conservation of the fish resources in Erhai Lake.

Comparative study of the reproductive biology of two congeneric and introduced goby species: implications for management strategies

A full understanding of life history characteristics of invasive species is a fundamental prerequisite for the development of management strategies. Two introduced goby species (Rhinogobius cliffordpopei and Rhinogobius giurinus) have established highly abundant populations in Lake Erhai (China). In the present study, we examined the reproductive biology of these two species with the aim of improving the efficiency of management strategy. The results indicated that R. cliffordpopei spawned from February to June, whereas R. giurinus spawned from April to August. Rhinogobius cliffordpopei showed higher gonado-somatic indices and had larger eggs than R. giurinus. The adult sex ratio of R. cliffordpopei was female skewed, but that of R. giurinus was equal. Rhinogobius cliffordpopei showed a male-skewed sexual size dimorphism, whereas the body size of R. giurinus varied only slightly between males and females. The different reproductive traits appear as a crucial biologic aspect for developing control programs. Specifically, control measures should be implemented and/or intensified from September to February for R. cliffordpopei and from January to April for R. giurinus. The body size of the smaller R. cliffordpopei females is the determinant for minimal mesh size of the nets used in physical removals of R. cliffordpopei.

Habitat segregation between two congeneric and introduced goby species

Spatial segregation is one of the most important mechanisms that facilitates coexistence among competing species. Large populations of two introduced and congeneric goby species (Rhinogobius giurinus and Rhinogobius cliffordpopei) now co-occur in Lake Erhai, a plateau lake in the Yunnan-Guizhou Plateau (China). Herein we quantified the spatio-temporal distribution of the two species to determine whether spatial segregation occurred within the same ecosystem. A total of 67,819 individuals of R. giurinus and 36,043 of R. cliffordpopei were sampled across four seasons. The results indicated that R. giurinus mostly occupied profundal habitat (PH) while R. cliffordpopei mainly used littoral habitat (LH). Correlation analysis revealed the abundance of R. giurinus was positively associated with deep water, silt and coarse sand substrata, whereas the distribution of R. cliffordpopei was positively associated with high densities of macrozooplanktons and high abundances of other fish species, high concentration of dissolved oxygen and high densities of submerged macrophytes. Except in spring, the body condition of R. giurinus was significantly higher in the PH than in the LH. The body condition of R. cliffordpopei did not differ significantly between habitats in the four seasons. These findings demonstrate that the two congeneric and introduced goby species occupy distinct habitats, indicating that spatial segregation enables coexistence of the two invasive species at high abundances within an ecosystem.

Predicting fish assemblages and diversity in shallow lakes in the Yangtze River basin

Habitat modifications induced by humans severely impact biotic components of freshwater ecosystems. In China, shallow lakes in the Yangtze River basin are facing severe habitat degradation induced by pollution, habitat losing, macrophytes disappearing and fishery activities. Effectively modeling the fish communities on the basis of biotic and abiotic environmental descriptors would be helpful to understand the relationships between fish and their environment, and to develop suitable conservation strategies to sustain the biodiversity in these ecosystems. From 2007 to 2009, investigations were carried out on fish and their environment in 6 lakes distributed in the mid-reach of the Yangtze River basin. According to the CPUE values of each fish species from each sampling, 117 datasets were ordinated using self-organizing map (SOM). Fish communities were classified into three clusters of species assemblages, spatial and temporal distributions were showing in it. Seasonal changes in fish community were more obvious in vegetated habitats than in unvegetated areas. The total CPUE, fish diversity and species richness were significantly different among the assemblages ( p < 0.01). Based on the indicative value of each species in each cluster calculated by Indval method, 16 species were identified as indicators: 13 indicators in cluster G1 are pelagic or benthopelagic fish, the only one indicator species in G2 is a tolerant species ( Culter dabry B.), while the other two indicator species in G3 are demersal fish ( Rhinogobius giurinus R. and Odontobutis obscurus T. & G.). These results are in agreement with the contributions of different ecological groups of fish in each assemblage in the trained SOM, pelagic and benthopelagic fish were found having more activities in spring and winter, while more activities of demersal fish were found in summer and autumn. Fish community assemblages, the total fish CPUE, diversity and species richness in those lakes were then predicted by 15 abiotic and biotic factors using random forest (RF) and classification and regression tree (CART) predictive models. The predicted assignment of each site unit to the correct assemblage had an average success of 74.4% and 60.7% in RF and CART models, respectively. The dominant variables for discriminating three fish assemblages were water depth, distance to the bank and total phosphorus. While the two important variables in prediction fish CPUE, diversity and species richness were lake surface area and water depth, density of rotifer and water depth, water depth and water temperature, respectively. The overall percentages of successful prediction varied from 56.5% to 67% utilizing leave-one-out for cross-validation tests.

Selection of spawning habitat by several gobiid fishes in the subtidal zone of a small temperate estuary

We examined the spawning sites of several gobiid fishes in the subtidal zone of a small temperate estuary and determined the relationship of the nest abundance of each species with several environmental conditions, including water temperature, salinity, median particle size, proportion of silt and clay, current width, maximum water depth, distance from each site to the river mouth, and density of objects (boulders, cobbles, empty oyster shells, and empty clam shells) in the water. During this study, we found 115 nests belonging to the following six species: Favonigobius gymnauchen, Tridentiger obscurus, Leucopsarion petersii, Acanthogobius lactipes, Rhinogobius giurinus, and Tridentiger trigonocephalus. Stepwise multiple regression analysis, which was used to determine the best model for the nest abundance of all species, revealed that the nest abundance of each species clearly increased with an increase in the density of spawning substrates, such as cobbles and bivalve shells. These results show that the density of spawning substrates is a crucial factor affecting the selection of spawning habitats by each species.

Fish Communities in Small and Intermediate Streams in Guangxi Province, China

ABSTRACT We examined the relationship between fish species composition and environmental and biogeographical variables in 26 small and intermediate streams in the Guangxi Province. The variables estimated were stream width, stream order, vegetation cover, bottom substrate, altitude, longitude, and latitude. Altogether 4,433 specimens of 36 species were collected. Rhinogobius giurinus (Gobiidae) and Opsariichtys bidens (Cyprinidae) were the most common species, and they were found at 16 of the localities. Species richness was correlated with stream width. Canonical Correspondence Analysis showed that longitude was the only environmental variable that significantly explained community composition of the fishes. Intensive land use is suggested to be a cause off the lack of correlation with other environmental variables. Two fish species assemblages could be distinguished, one eastern and one western.

Egg and clutch sizes of a goby Rhinogobius giurinus in the Aizu River, Kii Peninsula, Japan

Egg and clutch sizes, and gonad somatic index (GSI) at maturity of the amphidromous goby Rhinogobius giurinus were examined in the Aizu River, Wakayama Prefecture, Japan. The goby tended to have a larger clutch size, with smaller eggs, and matured at the lower GSI, compared with those in the three sympatric amphidromous species of R. brunneus complex. Higher water temperature and abundant food conditions may affect the optimal egg size in R. giurinus. Besides, higher larval survival rate during downstream migration may affect lower GSI at maturity in this goby that usually inhabits lower reaches of the river.