Galaxias and Climate Change

Thermal history influences thermal tolerance of freshwater fish

Compared to other climate regions of the world, Mediterranean regions are likely to experience more severe effects of climate change as rainfall decreases and temperatures increase. Global climate change models predict a reduction in rainfall and rise in the temperature of rivers in South Africa’s Cape Fold Ecoregion (CFE) – a Mediterranean region in the south-west corner of the country.

In the climate change context and with the prediction that stream temperatures will increase, determining thermal thresholds of freshwater fish in relation to their thermal history (the temperature in the river where they live) is a key element in understanding the potential impacts climate change and a rise in stream temperatures will have on already threatened freshwater fish.

new study published in the Journal of Thermal Biology by Toni Olsen and co-authors at the FRC investigated the influence of thermal history on a small, endemic species of freshwater fish – the Cape Galaxias.

Results of the study show that we can predict the thermal limits (how hot they can handle) of these fish (and potentially other fish living in Mediterranean regions) from the temperature of the river where they live, which has important implications for understanding climate change impacts on river ecosystems and managing them accordingly.

EFT Account Details

Account Name:               Freshwater Research Centre NPC 
Bank:                                 Nedbank Limited
Account No:                     102 680 5341    
Branch Code:                   104 309
Swift Code:                       NEDSZAJJ

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