Browsing All Posts filed under »physiology«

What drives regional differences in streamflow?

October 8, 2018

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Typically, large-scale models of stream flow take into account the interaction between climate and vegetation (which determines evapotranspiration) and landscape features that dictate how non-evaporated water is diverted to soil, groundwater and overland flow.  However, there are often strong spatial variations in streamflow drivers, which can limit the usefulness of global models.  Researchers drew on […]

Research on insect emergence warms up

October 8, 2018

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Long-term data show that climate change affects ecosystem functioning and the body size distributions of animal species, but more information is needed to understand the mechanisms underlying these changes.  There’s a need for experimental studies that take account of linkages between the aquatic and terrestrial environment and that simulate changes in the intensity and frequency […]

Small fish species are more at risk

October 8, 2018

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Large-bodied animal species tend to have relatively low fecundity, long generation times and slow growth rates, which makes for low population turnover and a heightened risk of extinction.  This trend seems to be true for vertebrates such as mammals and marine fish, but not, it seems, for freshwater fish.  Australian ecologists explored the relationship between […]

Fish life histories: filling in the gaps

July 5, 2018

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Estimates of life history parameters such as age at maturity, maximum body size and rates of growth and mortality play a crucial role in understanding and managing animal populations, but in the case of many species they’re lacking or poorly measured.  Fortunately however, compilations of existing estimates now exist, and these databases open up opportunities […]

Triggers for algal blooms: peak temperatures aren’t always important

July 5, 2018

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There are concerns that human impacts  on freshwater systems – particularly temperature increases linked to climate change and nutrient enrichment caused by run-off and pollution – are encouraging the spread of blue-green algae (cyanobacteria) capable of generating toxic blooms that threaten human and animal health.  One such case is the recent spread of Cylindrospermopsis raciborskii, […]

A mature approach to growth data

March 25, 2018

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The age at which an animal matures is a key life history trait with implications for ecology, evolution and population dynamics, but data on maturation can be costly to collect. However, in many animals growth occurs in two phases, with a change-point at maturity, which means that it’s sometimes possible to estimate the maturation age […]

Ironing out harmful algal blooms

September 25, 2017

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An understanding of how iron affects the supply of nutrients in aquatic systems may open the door to better success in managing harmful algal blooms. In highly productive lakes, the release of phosphorus stored in the bottom sediment can encourage bloom development, but nutrient release is retarded in the presence of iron, which precipitates phosphorus […]