scholarly journals Annual and Monthly Variation in Species Composition and Catches of Fishes from the Tabusintac River Estuary in the Southern Gulf of St. Lawrence

2009 ◽  
Vol 123 (1) ◽  
pp. 48 ◽  
Author(s):  
A. M. Herrell ◽  
D. A. Methven
Keyword(s):  
Atlantic Salmon ◽  
Species Composition ◽  
Brook Trout ◽  
White Perch ◽  
River Estuary ◽  
Fish Fauna ◽  
Freshwater Species ◽  
Total Catch ◽  
Additional Species ◽  
Sampling Gear

A total of 7130 fish from 13 taxa were collected during summer and autumn, 2002-2005 using box traps at two sites in the Tabusintac River Estuary, New Brunswick, Canada. The objective was to determine seasonal change in species composition and catches, and to access change in annual returns of Atlantic Salmon, an important recreational fishery during autumn on the Tabusintac, Miramichi and neighboring rivers. Taxa richness and composition varied annually and from trap to trap. Richness ranged from 8-10 taxa annually and catches were usually highest in the trap closest to the ocean despite its slightly smaller size. Taxa contributing greater than one percent of the total catch during the four years of sampling included six diadromous taxa: Blueback Herring and Alewife (41.65%), Striped Bass (21.54%), Atlantic Salmon (3.98%), Tomcod (2.95%), Brook Trout (1.05%), American Eel (5.27%); one freshwater species, White Sucker (11.96%); one marine species, Winter Flounder and one resident estuarine species, Smooth Flounder which together account for 11.19% of the total catch. The remaining five species (American Smelt, Northern Pipefish, White Perch, Cunner, Sea Lamprey) contributed 0.39% of the total catch. The fish fauna 14-15 km up the Tabusintac River was not species rich, due in large part to the limited sampling time each year and due to fishing with just one sampling gear, a stationary box trap. Additional species would have been collected if smaller mesh sampling gear were used. Comparisons were made with other studies and the phenology of the dominant species on the Tabusintac and Miramichi River Estuaries during the ice free season is established. Most catches appear to be related to pre- or post-spawning movements of anadromous fishes.

System for Sampling Large Trawl Catches of Research Vessels

1976 ◽  
Vol 33 (4) ◽  
pp. 833-839 ◽  
Author(s):  
S. E. Hughes
Keyword(s):  
Species Composition ◽  
Dominant Species ◽  
Puget Sound ◽  
Length Distribution ◽  
Handling Time ◽  
Total Catch ◽  
Sampling Gear ◽  
Trawl Catches ◽  
Large Research

Procedures and sampling gear designed 1) to sample large research trawl catches prior to sorting by species and 2) to reduce catch handling time and permit an increase in the number of hauls per cruise, are discussed and illustrated. The rationale behind the method relies on the hypothesis that species and size stratification in the codend of the trawl are bilaterally symmetrical The codend is positioned above a deck bin prior to releasing the catch so that a sampling net can be lifted from the deck bin to remove about one half of the total catch. The sampled portion is processed on a fish sorting table, and the unused portion brailed overboard by a net which lines the entire deck bin. Tests conducted in Puget Sound indicated that the species composition and length distribution in the sample adequately represented the total catch; errors greater than 25% were usually restricted to species composing less than 5% of the catch, and for dominant species errors were less than 10%.

Atlantic salmon (Salmo salar) in the lower Nastapoka River, Quebec: distribution and origins of salmon in eastern Hudson Bay

1991 ◽  
Vol 69 (6) ◽  
pp. 1674-1681 ◽  
Author(s):  
Roderick Morin
Keyword(s):  
Atlantic Salmon ◽  
Brook Trout ◽  
Reproductive Potential ◽  
River Estuary ◽  
Maximum Size ◽  
Hudson Bay ◽  
Gill Net ◽  
Salmon Population ◽  
Freshwater Zone ◽  
Rapid Current

Atlantic salmon have been occasionally reported along eastern Hudson Bay, north of Richmond Gulf; however, in the Nastapoka River estuary they dominated gill-net catches over a 3-year period. The results of surveys of native fishermen suggest that this is the only anadromous stock in eastern Hudson Bay. Salmon are also present in the Nastapoka River above a 35-m coastal escarpment. It is proposed that they colonized the river from Ungava Bay by headwater exchange with the Koksoak River following deglaciation. Atlantic salmon and brook trout accounted for >80% of gill-net catches in the lower Nastapoka River and estuary. Salmon and trout were similar in size up to age 7. Trout growth was linear whereas salmon growth slowed, resulting in a smaller maximum size, but longevity was greater in salmon than in trout. Salmon matured at a greater age and had lower fecundity and reproductive potential than trout. In the estuary, both species consumed mainly littoral marine amphipods and marine fishes. The salmon population is located at the northern limit of the thermal optimum reported for the species. Habitat in the lower Nastapoka River may favour salmon over trout because of the rapid current in the restricted freshwater zone below the coastal waterfall. This habitat is threatened by the proposed diversion of headwaters for hydroelectric development.

The concept of local explosion in freshwater ecosystems

2013 ◽  
Vol 25 (1-2) ◽  
pp. 136-148
Author(s):  
I. V. Gryb
Keyword(s):  
Species Composition ◽  
Aquatic Environment ◽  
Arid Zone ◽  
Fish Fauna ◽  
River Basins ◽  
Freshwater Ecosystems ◽  
Human Society ◽  
Living Matter ◽  
Ecosystem Recovery ◽  
Average Temperature

The concept of an explosion in freshwater ecosystems as a result of the release of accumulated energy, accompanied by the destruction of the steady climax successions of hydrocenoses is presented. The typification of local explosions as well as methods for assessing their risk during the development of river basins are shown. The change in atmospheric circulation, impaired phases of the hydrological regime of rivers, increasing the average temperature of the planet, including in Polesie to 0,6 ºC, deforestation leads to concentration and release of huge amounts of unmanaged terrestrial energy, which manifests itself in the form of disasters and emergencies. Hydroecological explosion is formed as a result of multifactorial external influence (natural and anthropogenic) on the water body in a certain period of time. Moreover, its level at wastewater discharge depends on the mass of recycled impurities and behaved processing capacity of the reservoir, and the mass of dumped on biocides and the possibility of the water flow to their dilution and to the utilization of non-toxic concentrations. In all these cases the preservation of "centers of life" in the tributaries of the first order – local fish reproduction areas contributed to ecosystem recovery, and the entire ecosystem has evolved from equilibrium to non-equilibrium with further restructuring after the explosion and environmental transition to a new trophic level. It means that hydroecological explosion can be researched as the logical course of development of living matter in abiotic environmental conditions, ending abruptly with the formation of new species composition cenoses and new bio-productivity. The buffer capacity of the water environment is reduced due to re-development and anthropic transformation of geobiocenoses of river basins, which leads to a weakening of life resistance. This applies particularly to the southern industrial regions of Ukraine, located in the arid zone that is even more relevant in the context of increased average temperature due to the greenhouse effect, as well as to Polesie (Western, Central and Chernihiv), had been exposed to large-scale drainage of 60-80th years, which contributed to the degradation of peatlands and fitostroma. Imposing the western trace of emissions from the Chernobyl accident to these areas had created the conditions of prolonged hydroecological explosion in an intense process of aging water bodies, especially lakes, change in species composition of fish fauna and the occurrence of neoplasms at the organismal level. Under these conditions, for the existence of man and the environment the vitaukta should be strengthened, i.e. buffer resistance and capacitance the aquatic environment, bioefficiency on the one hand and balanced using the energy deposited - on the other. This will restore the functioning of ecosystems "channel-floodplain", "riverbed-lake", reducing the energy load on the aquatic environment. Hydroecological explosions of natural origin can not be considered a pathology – it is a jump process of natural selection of species of biota. Another thing, if they are of anthropogenic origin and if the magnitude of such an impact is on the power of geological factors. Hydroecological explosions can be regarded as a manifestation of environmental wars that consciously or unconsciously, human society is waging against themselves and their kind in the river basins, so prevention of entropy increase in the aquatic environment and the prevention of hydroecological explosions is a matter of human survival. While the man - is not the final link in the development of living matter, it can develop without him, as matter is eternal, and the forms of its existence are different.

scholarly journals The fish fauna of streams in the Madeira-Purus interfluvial region, Brazilian Amazon

Check List ◽  
2011 ◽  
Vol 7 (6) ◽  
pp. 768 ◽  
Author(s):  
Daniela de França Barros ◽  
Jansen Zuanon ◽  
Fernando Pereira De Mendonça ◽  
Helder Mateus Viana Espírito Santo ◽  
André Vieira Galuch ◽  
...  
Keyword(s):  
Species Richness ◽  
Species Composition ◽  
Fish Fauna ◽  
Brazilian Amazon ◽  
Neotropical Region ◽  
Environmental Conservation ◽  
Taxonomic Group ◽  
Conservation Strategies ◽  
Species Richness And Diversity ◽  
High Species Richness

Small headwaters streams of the Neotropical region usually have high species richness and diversity. This study aimed to investigate the species composition and abundance of fish fauna in the headwaters streams of the Madeira-Purus interfluvial plain in the Brazilian Amazon. A total of 22 streams of 1st to 3rd order were sampled during two expeditions at two separate locations in April-May and July of 2007. A total of 5508 fishes were captured using hand and small seine nets, belonging to 78 species, 22 families and six orders. Characiformes was the most diverse taxonomic group in the samples, followed by Gymnotiformes and Siluriformes. Our findings indicate that the fish fauna of streams in the Madeira- Purus interfluvial plain is both rich and diverse and should be considered during the implementation of strengthened environmental conservation strategies in this region. 

Rainbow trout (Oncorhynchus mykiss) habitat overlap with wild Atlantic salmon (Salmo salar) and brook trout (Salvelinus fontinalis) in natural streams: do habitat and landscape factors override competitive interactions?

2018 ◽  
Vol 75 (11) ◽  
pp. 1949-1959
Author(s):  
Scott D. Roloson ◽  
Kyle M. Knysh ◽  
Michael R.S. Coffin ◽  
Karen L. Gormley ◽  
Christina C. Pater ◽  
...  
Keyword(s):  
Rainbow Trout ◽  
Atlantic Salmon ◽  
Oncorhynchus Mykiss ◽  
Salmo Salar ◽  
Brook Trout ◽  
Salvelinus Fontinalis ◽  
Habitat Overlap ◽  
Atlantic Salmon Salmo Salar ◽  
Rainbow Trout Oncorhynchus Mykiss ◽  
Natural Streams

The purpose of this study was to update rainbow trout (Oncorhynchus mykiss) invasion status, delineate factors that increase the invasion probability, and quantify habitat overlap between invasive rainbow trout and native Atlantic salmon (Salmo salar) and brook trout (Salvelinus fontinalis) on Prince Edward Island, Canada. Analysis of landscape-level variables in 26 watersheds (14 with and 12 without rainbow trout) demonstrated that watershed slope, percent agricultural land use, and distance to the nearest rainbow trout population significantly increased the probability of rainbow trout establishment. Two independent reach-level fish community surveys were conducted by electrofishing in combination with habitat surveys. Reaches with rainbow trout had higher stream slope, Atlantic salmon were found in wider reaches with larger substrate, and brook trout were typically dominant in headwater reaches with finer substrate. Findings at multiple ecological scales illustrated that rainbow trout invasion success is positively influenced by the presence of high-slope habitat. Habitat separation of the three salmonid species indicates that competition with introduced rainbow trout may not be the most significant threat to native salmonid populations.

Historical Changes in Large River Fish Assemblages of the Americas

2005 ◽  
Keyword(s):  
New Mexico ◽  
North America ◽  
Gulf Of Mexico ◽  
Fish Assemblages ◽  
Fish Fauna ◽  
Rio Grande ◽  
Large River ◽  
Freshwater Species ◽  
The World ◽  
Native Fishes

<em>Abstract.</em>—The Rio Grande is the fourth longest river in North America and the 22nd longest in the world. It begins as a cold headwater stream in Colorado, flows through New Mexico and Texas, where it becomes warm and turbid and finally empties into the Gulf of Mexico. The diversity of native fishes is high in the Rio Grande ranging from freshwater salmonids in its upper reaches to coastal forms in the lower reaches. Historically, about 40 primary freshwater species inhabited the waters of the Rio Grande. Like many rivers throughout North America, the native fish fauna of this river has been irrevocably altered. Species once present are now extinct, others are threatened or endangered, and the majority of the remaining native fishes are declining in both range and numbers. Today, 17 of the 40 primary native freshwater fishes have been either extirpated in part or throughout the Rio Grande drainage. This chapter examines the river, its fauna, and its current plight.

Status of fish biodiversity and fishing on Hau River, Mekong Delta, Vietnam

2020 ◽  
Vol 56 ◽  
pp. 14
Author(s):  
Vu Ngoc Ut ◽  
Au Van Hoa ◽  
Huynh Phuoc Vinh
Keyword(s):  
Species Composition ◽  
Fish Species ◽  
Mekong Delta ◽  
Middle Part ◽  
Fishing Ground ◽  
Sampling Gear ◽  
Fish Biodiversity ◽  
Gill Net ◽  
Fishing Gears ◽  
The Status

Fish biodiversity on Hau (Bassac) river was investigated to assess the status of species composition and fishing by fishing gears during a year. Sampling was implemented monthly at the upper part (An Giang province), middle part (Can Tho City) and lower part (Soc Trang province) of Hau River using trawl net as main sampling gear. Additionally, fish composition was also recorded from four other most popular fishing gears including cast net, gill net, fixed net and hook operated in the study sites. Fish species composition was determined by fishing gears and their abundance (CPUE) was calculated only from the main sampling gear (trawl net). The results showed that a total of 176 fish species belonging to 16 orders and 49 families was recorded. Perciformes was the most abundant group with 51 species followed by Cypriniformes with 46 species. The number of fish species was decreasing from upper part to lower part. Trawl net was considered the most destructive gear as up to 145 fish species caught by this device, followed by gill net with 98 species, fixed net 75, cast net 57, and hooks 16 species. CPUE was very low ranging from  0.53 kg.ha−1 h−1 to 26.30 kg.ha−1 h−1. Higher CPUE was recorded at lower part in compared to upper part and middle part, and at dry season in compared to rainy season. Regulation on fishing gears, fishing ground and season should be taken into consideration to protect and conserve the resources.

Measurement of circulating thyroxine in several freshwater teleosts by competitive binding analysis

1973 ◽  
Vol 51 (1) ◽  
pp. 49-53 ◽  
Author(s):  
D. A. Higgs ◽  
J. G. Eales
Keyword(s):  
Brook Trout ◽  
Competitive Binding ◽  
Freshwater Species ◽  
Thyroxine Binding Globulin ◽  
Binding Analysis ◽  
Freshwater Teleosts

A competitive binding analysis using human thyroxine-binding globulin (TBG) and Sephadex columns was the most satisfactory of several methods tested for measuring fish plasma thyroxine concentrations.Thyroxine levels were usually less than 1 μg and in most cases less than 0.5 μg per 100 ml plasma for laboratory-held brook trout and nine other freshwater species.

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