Environmental Determinants Influencing Fish Community Structure and Diversity in Two Distinct Seasons among Wetlands of Northern Region (Ghana)

Fish community structure was assessed in six wetlands using cast nets, to correlate with environmental variables with diversity and distribution patterns, from 2010 to 2012. A total of 2,239 individuals belonging to 44 species and 1,938 individuals belonging to 40 species were sampled in the dry and wet seasons. Mochokid and Mormyrid families dominated fish community and constituted 14.8%, respectively, followed by Alestids (12.9%) and Chlariids (11.1%). Rarer taxons were centropomids, channids, malapteruds, and oesteoglossids and represented 1.9%, respectively. Overall, CPUE per net did not vary significantly (Tukey HSD test,p=0.27) in the dry and wet seasons. Wuntori marsh consistently showed dominance in mean monthly CPUE per net (dry =115±4.5; wet =107±7.7seasons), while Bunglung constructed wetland was the least recorded (dry =56.5±6.2; wet =58.3±4.1seasons). Fish diversity and richness differed significantly (F=0.11,p=0.03) among seasons. Environmental disturbances were season-specific and did not differ significantly (F=0.16,df=14,p=0.97) among sites. A DCA ordination explained 69% variability in fish distribution patterns, while PCA showed that 81.8% of nitrate-nitrogen, phosphate, and grazing intensity on axis 1 and conductivity, temperature, and turbidity on axis 2 influenced fish community structure. Wetland conservation must be promoted to sustain fish abundance and overall ecosystem stability.

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Fish community structure along altitudinal gradients with relation to environmental variables in Ratuwa River of Eastern, Nepal

Our Nature ◽

10.3126/on.v19i1.41265 ◽

2021 ◽

Vol 19 (1) ◽

pp. 70-81

Author(s):

Dipak Rajbanshi ◽

Jash Hang Limbu ◽

Niraj Khadka ◽

Prakash Kumar ◽

Jeevan Kumar Gurung ◽

...

Keyword(s):

Community Structure ◽

Altitudinal Gradient ◽

Fish Community ◽

Fish Diversity ◽

Fish Assemblage Structure ◽

Fish Community Structure ◽

Brachydanio Rerio ◽

Altitudinal Gradients ◽

Space And Time ◽

Significant Difference

Studies on fish community structure along altitudinal gradients of rivers are lacking in Nepal. This study was carried out to gauge the fish diversity and composition along elevational gradient in Ratuwa River. The altitudinal gradient varies between 70 m to 1300 m. Fish samples were collected based on habitat representativeness from April (spring) 10-18, July (summer) 10-18, October (autumn) 10-18, 2020 and January (winter) 10-18, 2021. A total of 3447 specimens representing 4 orders, 14 families and 36 species were identified. Both fish diversity and abundance of studied ichthyofauna vary with altitudinal gradient. The present study affirmed that fish species of Opsarius bendelisis, Schistura multifasciatus, Garra annandalei, Brachydanio rerio, Aspidoparia morar, and Schistura scaturigina are the major contributory species (>1%) for both space and time spectrums. Fish community structure testing for both to space and time showed significant difference in spatial spectrum (R=0.72, P<0.01) but no significant difference in temporal variation (R=-0.034, P>0.05). The present results hinted that fish assemblage structure varied significantly from low to high elevations, altitude, water temperature, water velocity, dissolved oxygen and pH was found as major influential factors (P<0.05) for species distribution.

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Marine Fishes of Caño Island Biological Reserve: Reef fish community structure and updated list for the coastal fish.

Revista de Biología Tropical ◽

10.15517/rbt.v63i1.23098 ◽

2016 ◽

pp. 97-116

Author(s):

Eva Salas ◽

Cristina Sánchez-Godínez ◽

Andrea Montero-Cordero

Keyword(s):

Community Structure ◽

Reef Fish ◽

Fish Species ◽

Fish Community ◽

Coral Cover ◽

Fish Diversity ◽

Fish Community Structure ◽

Coastal Fish ◽

Reef Fish Community ◽

Biological Reserve

Biogeographically, the Caño Island Biological Reserve (CIBR) is of strategic importance, since it is located in the center of the Panamic Province (Costa Rica and Panama), characterized by a peak in fish species richness within the Tropical Eastern Pacific (TEP). Despite its importance, fish community structure around the island has not been deeply studied, and coastal fish diversity records need to be updated. The aims of the study were: 1) to describe the community structure of the reef fish community of CIBR and 2) to update the list of the coastal fish species recorded until today. For the first objective, 50 stationary fish counts were conducted at 10 locations around Caño Island, in which 79 species, belonging to 32 families, were registered. The most abundant family was Pomacentridae, and the most abundant species was Chromis atrilobata. Planktivorous and carnivorous fish were the most abundant. The existence of a relationship between coral cover and the presence of herbivorous grazers was highlighted within the analysis. Additionally, species composition was compared by site and this revealed that “El Barco” has an abundant presence of snappers. For the second objective, published fish species records were collected for the CIBR and 35 new records were added, for a total of 212 coastal fish species, which represents approximately 17% of coastal fish diversity in the TEP. This work presents a baseline for fish monitoring and mangement measures in this marine protected area.

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Fish Community Structure and Environmental Correlates in Nepal’s Andhi Khola, Province No. 4, Syangja

Borneo Journal of Resource Science and Technology ◽

10.33736/bjrst.2510.2020 ◽

2020 ◽

Vol 10 (2) ◽

pp. 85-92

Author(s):

Jash hang Limbu ◽

BISHNU BHURTEL ◽

ASHIM ADHIKARI ◽

PUNAM GC ◽

MANIKA MAHARJAN ◽

...

Keyword(s):

Community Structure ◽

Spatial Variation ◽

Fish Assemblage ◽

Environmental Variables ◽

Fish Community ◽

Mesh Size ◽

Fish Diversity ◽

Fish Assemblage Structure ◽

Fish Community Structure ◽

Significant Difference

The study of correlations between fish diversity, environmental variables and fish habitat aspects at different space and time scales of Nepal’s rivers and streams is scanty. This study investigated spatial and temporal patterns of fish assemblage structure in Nepal’s Andhi Khola. The field survey was conducted from September 2018 to May 2019 and the fishes were sampled from three sites using a medium size cast net of mesh size ranging from 1.5 to 2.5 cm and gill net having 2-3 cm mesh size, 30-35 feet length and 3-4 feet width, with the help of local fisher man. A total of 907 individuals representing 15 species belonged to four orders, six families and 11 genera were recorded during the study time. To detect the feasible relationships between fish community structure and environmental variables, we executed a Canonical Correspondence Analysis (CCA). Based on similarity percentage (SIMPER) analysis, the major contributing species are Barilius barila (26.15%), Barilius vagra (20.48%), Mastacembelus armatus (8.04%), Puntius terio (6.64%), and Barilius bendelisis (5.94%). One-way analysis similarity (ANOSIM) tried out for both time and space variations in fish community structure suggested that there was a significant difference in temporal variation (R = 0.794, P = 0.0037) but no significant difference in spatial variation (R = -0.18, P = 0.923). Results from the Canonical Correspondence Analysis (CCA) vindicated that dissolved oxygen, free carbon-dioxide and total hardness were the principle physio-chemical correlates of fish assemblage structure. One-way analysis of similarity (ANOSIM) on the Non-metric Multidimensional Scaling (NMDS) showed significant difference between spring, autumn and winter season but no significant difference was found in spatial variation. The extraction and transportation of boulders, cobbles, pebbles, sand mining, haphazard ongoing road development and dam construction for the irrigation without fish ladders were found to be existing threats to the fish diversity of Andhi Khola. Keywords: Fish assemblage, multivariate analysis, rivers, spatio-temporal, streams

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Fish community structure, habitat complexity, and soundscape characteristics of patch reefs in a tropical, back-reef system

Marine Ecology Progress Series ◽

10.3354/meps12829 ◽

2019 ◽

Vol 609 ◽

pp. 33-48 ◽

Cited By ~ 7

Author(s):

RP Lyon ◽

DB Eggleston ◽

DR Bohnenstiehl ◽

CA Layman ◽

SW Ricci ◽

...

Keyword(s):

Community Structure ◽

Habitat Complexity ◽

Fish Community ◽

Back Reef ◽

Fish Community Structure ◽

Patch Reefs ◽

Reef System

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Dissolved oxygen and temperature best predict deep-sea fish community structure in the Gulf of California with climate change implications

Marine Ecology Progress Series ◽

10.3354/meps13240 ◽

2020 ◽

Vol 637 ◽

pp. 159-180

Author(s):

ND Gallo ◽

M Beckwith ◽

CL Wei ◽

LA Levin ◽

L Kuhnz ◽

...

Keyword(s):

Climate Change ◽

Community Structure ◽

Community Composition ◽

Environmental Conditions ◽

Deep Sea ◽

Gulf Of California ◽

Fish Community ◽

Demersal Fish ◽

Fish Community Structure ◽

Explained Variance

Natural gradient systems can be used to examine the vulnerability of deep-sea communities to climate change. The Gulf of California presents an ideal system for examining relationships between faunal patterns and environmental conditions of deep-sea communities because deep-sea conditions change from warm and oxygen-rich in the north to cold and severely hypoxic in the south. The Monterey Bay Aquarium Research Institute (MBARI) remotely operated vehicle (ROV) ‘Doc Ricketts’ was used to conduct seafloor video transects at depths of ~200-1400 m in the northern, central, and southern Gulf. The community composition, density, and diversity of demersal fish assemblages were compared to environmental conditions. We tested the hypothesis that climate-relevant variables (temperature, oxygen, and primary production) have more explanatory power than static variables (latitude, depth, and benthic substrate) in explaining variation in fish community structure. Temperature best explained variance in density, while oxygen best explained variance in diversity and community composition. Both density and diversity declined with decreasing oxygen, but diversity declined at a higher oxygen threshold (~7 µmol kg-1). Remarkably, high-density fish communities were observed living under suboxic conditions (<5 µmol kg-1). Using an Earth systems global climate model forced under an RCP8.5 scenario, we found that by 2081-2100, the entire Gulf of California seafloor is expected to experience a mean temperature increase of 1.08 ± 1.07°C and modest deoxygenation. The projected changes in temperature and oxygen are expected to be accompanied by reduced diversity and related changes in deep-sea demersal fish communities.

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