Nonconsumptive effects of Brook Trout predators reduce secondary production of mayfly prey

Fish yields of Ruditapes philippinarum have been decreased and the resources have not yet recovered. It needs to clarify food sources of R. philippinarum, and relationship between primary and secondary production of it. The purpose on this study is to reveal transfer efficiency from primary producers to R. philippinarum and food sources of R. philippinarum. The field investigation was carried out to quantify biomass of R. philippinarum and primary producers on intertidal sand flat at Zigozen beach in Hiroshima Bay, Japan. In particular, photosynthetic rates of primary producers such as Zostera marina, Ulva sp. and microphytobenthos were determined in laboratory experiments. The carbon and nitrogen stable isotope ratios for R. philippinarum and 8 potential food sources (microphytobenthos, MPOM etc) growing in the tidal flat were also measured. In summer 2015, the primary productions of Z. marina, Ulva sp. and microphytobenthos were estimated to be 70.4 kgC/day, 43.4 kgC/day and 2.2 kgC/day, respectively. Secondary production of R. philippinarum was 0.4 kgC/day. Contribution of microphytobenthos to R. philippinarum as food source was 56-76% on the basis of those carbon and nitrogen stable isotope ratios. Transfer efficiency from microphytobenthos to R. philippinarum was estimated to be 10-14%. It was suggested that microphytobenthos might sustain the high secondary production of R. philippinarum, though the primary production of microphytobenthos was about 1/10 compared to other algae.

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Spatial and seasonal variation in brook trout diet, growth, and consumption in a complex Appalachian watershed

10.33915/etd.2047 ◽

2004 ◽

Cited By ~ 1

Author(s):

David W. Thorne

Keyword(s):

Seasonal Variation ◽

Brook Trout ◽

Spatial And Seasonal Variation

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Secondary Production of Net-Spinning Caddisflies (Trichoptera: Curvipalpia) in an Ozark Stream

10.21236/ada228640 ◽

1990 ◽

Author(s):

David E. Bowles ◽

Robert T. Allen

Keyword(s):

Secondary Production

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Organochlorine Residues in Brook Trout and Yellow Perch From New Brunswick and Nova Scotia (Canada) Lakes

Water Quality Research Journal ◽

10.2166/wqrj.1987.027 ◽

1987 ◽

Vol 22 (3) ◽

pp. 352-364

Author(s):

R. Peterson ◽

S. Ray

Keyword(s):

Nova Scotia ◽

New Brunswick ◽

Brook Trout ◽

Yellow Perch ◽

Intensive Agriculture ◽

Fish Tissues ◽

North Central ◽

Ddt Metabolites ◽

Headwater Lakes

Abstract Brook trout and yellow perch collected while surveying New Brunswick and Nova Scotia headwater lakes were analyzed for DDT metabolites, chlordane, hexacyclohexane isomers, hexachlorobenzene, toxaphene and PCB’s. Concentrations of DDT metabolites were much higher from fish taken from lakes in north-central N.B. (200-700 ng/g wet wt) than from fish taken elsewhere (<10 ng/g). Seventy to 90% of the DDT metabolites was DDE. Chlordane (3-13 ng/g) was analyzed in seven trout, six of them from central N.B. areas with intensive agriculture. Isomers of hexachlorocyclohexane were in highest concentration from north-central N.B. (10-20 ng/g), eastern N.S. (5-15 ng/g) and southern N.B. (5-20 ng/g). In most cases, alpha-hexachlorocyclohexane (lindane) was the isomer in highest concentration. Concentrations of hexachlorobenzene in fish tissues was highly variable with no obvious geographic bias. PCB’s were detected in very few fish, and no toxaphene was detected.

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Effects of genetic origin on phenotypic divergence in Brook Trout populations stocked with domestic fish

Ecosphere ◽

10.1002/ecs2.3119 ◽

2020 ◽

Vol 11 (5) ◽

Author(s):

Philippine Gossieaux ◽

Émilie Lavoie ◽

Pascal Sirois ◽

Isabel Thibault ◽

Louis Bernatchez ◽

...

Keyword(s):

Brook Trout ◽

Genetic Origin ◽

Phenotypic Divergence

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Tracking the Fate of Aluminium in the EU Using the MaTrace Model

Resources ◽

10.3390/resources10070072 ◽

2021 ◽

Vol 10 (7) ◽

pp. 72

Author(s):

Gabriela Jarrín Jácome ◽

María Fernanda Godoy León ◽

Rodrigo A. F. Alvarenga ◽

Jo Dewulf

Keyword(s):

Secondary Production ◽

Economic Importance ◽

Baseline Scenario ◽

Light Weight ◽

The European Union ◽

High Corrosion Resistance ◽

Product Categories ◽

The Impact ◽

Selective Collection ◽

The Eu

Aluminium is a metal of high economic importance for the European Union (EU), presenting unique properties (e.g., light weight and high corrosion resistance) and with applications in important sectors (e.g., transportation, construction and packaging). It is also known for its high recyclability potential, but relevant losses occur in its life cycle, compromising the amount of aluminium available for secondary production. A novel methodology that allows the identification of these losses and their impact on the aluminium flows in society is the MaTrace model. The objective of this article is to perform a dMFA of the secondary production of aluminium in the EU technosphere using the modified version of MaTrace, in order to estimate flows of the metal embedded in 12 product categories. Twelve scenarios were built in order to assess the impact of changes in policies, demand and technology. The flows were forecasted for a period of 25 years, starting in 2018. The results of the baseline scenario show that after 25 years, 24% of the initial material remains in use, 4% is hoarded by users, 10% has been exported and 61% has been physically lost. The main contributor to the losses is the non-selective collection of end-of-life products. The results of the different scenarios show that by increasing the collection-to-recycling rates of the 12 product categories, the aluminium that stays in use increase up to 32.8%, reaffirming that one way to keep the material in use is to improve the collection-to-recycling schemes in the EU.

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Evidence for the Use of Mucus Swabs to Detect Renibacterium salmoninarum in Brook Trout

Pathogens ◽

10.3390/pathogens10040460 ◽

2021 ◽

Vol 10 (4) ◽

pp. 460

Author(s):

Tawni B. Riepe ◽

Victoria Vincent ◽

Vicki Milano ◽

Eric R. Fetherman ◽

Dana L. Winkelman

Keyword(s):

Brook Trout ◽

Sampling Methods ◽

Kidney Tissue ◽

Detection Methods ◽

Fish Health ◽

Wild Populations ◽

Renibacterium Salmoninarum ◽

Tissue Samples ◽

Future Studies ◽

Aquaculture Facilities

Efforts to advance fish health diagnostics have been highlighted in many studies to improve the detection of pathogens in aquaculture facilities and wild fish populations. Typically, the detection of a pathogen has required sacrificing fish; however, many hatcheries have valuable and sometimes irreplaceable broodstocks, and lethal sampling is undesirable. Therefore, the development of non-lethal detection methods is a high priority. The goal of our study was to compare non-lethal sampling methods with standardized lethal kidney tissue sampling that is used to detect Renibacterium salmoninarum infections in salmonids. We collected anal, buccal, and mucus swabs (non-lethal qPCR) and kidney tissue samples (lethal DFAT) from 72 adult brook trout (Salvelinus fontinalis) reared at the Colorado Parks and Wildlife Pitkin Brood Unit and tested each sample to assess R. salmoninarum infections. Standard kidney tissue detected R. salmoninarum 1.59 times more often than mucus swabs, compared to 10.43 and 13.16 times more often than buccal or anal swabs, respectively, indicating mucus swabs were the most effective and may be a useful non-lethal method. Our study highlights the potential of non-lethal mucus swabs to sample for R. salmoninarum and suggests future studies are needed to refine this technique for use in aquaculture facilities and wild populations of inland salmonids.

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