Browsing All Posts filed under »habitat diversity«

How the food web affects river restoration

October 8, 2018

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River restoration commonly  concentrates on improving habitat quality for threatened fish populations.  However, because stream fish are strongly influenced by food availability, competition and predation, a case can be made for also incorporating food web modelling into the restoration process.  A group of environmental scientists developed an ecosystem model and applied it to a river-floodplain […]

Lakes are good for river species

October 8, 2018

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While it’s known that terrestrial landscape features, such as soil type, topography and land use, influence the abundance and distribution of stream fish, only a few studies have considered the possible effects of lakes on stream fish populations.  Biologists carried out a three-year study on native brook trout (Salvelinus fontinalis) in 36 streams in the […]

Floodplain fisheries and overexploitation

October 8, 2018

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The floodplain fishery in the Pantanal region of South America, one of the biggest wetlands in the world,  illustrates the difficulties often faced in managing resources in complex, highly changeable environments.  In the late 1970s and early 1980s, traditional small-scale commercial fishers accounted for around three-quarters of the fish catch.  In the absence of scientific […]

Stream assessment by citizen scientists

July 5, 2018

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Although the potential spatial and temporal coverage of environmental data sets generated by citizen scientists is enormous, the quality of volunteer data sets depends on the use of simple, clearly defined and standardised methods.  To answer the need for an approach that can be used by citizen scientists to assess physical habitats and human pressures […]

Successful stream restoration can take decades

July 5, 2018

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Although assessments of the success of stream restoration projects depend on post-restoration monitoring, in most cases the monitoring period ends long before the system reaches full functional maturity.   Given this situation, it can be helpful to refer to performance curves that forecast how stream restoration projects will perform over time.  American environmental scientists set out […]

Freshwater fish surveys: direct observation works well

March 26, 2018

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Although surveys of freshwater fish populations often rely on electrofishing, it’s difficult to use this technique in some habitats. An alternative sampling method is direct observation by snorkelling, an approach often applied in marine environments.  While comparisons of the sampling efficiency of electrofishing and snorkelling have been carried out, most of them have been based […]

Freshwater conservation needs flagship umbrellas

March 26, 2018

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Flagship species are surrogate species that are used to raise public awareness and funds for conservation, while umbrella species are those which ensure that a wide range of co-occurring species are conserved when they themselves are afforded protection.  In principle, conservation efforts should be enhanced by identifying species – dubbed “flagship umbrellas” – that combine […]