By Mischa Turschwell
Climate change may lead to the extinction of many fish species around the world, but it is not clear whether local actions can help mitigate the impacts of climate change. Our recent work shows that planting trees can cool down streams and help offset the impacts of global warming on threatened Australian fish.
We combined previous research on Northern river blackfish (Gadopsis marmoratus), a threated species in the upper Condamine River, Australia, to test how climate change and replanting trees along riverbanks (riparian restoration) might affect blackfish survival.
Compared to current climatic conditions, climate change may reduce the chances of blackfish survival, because they prefer cooler habitats.
However, local actions could help save the blackfish. Many streams that blackfish use have had their vegetation cut down and grassy banks are maintained by grazing of cattle and sheep.
We found that the impact of climate change could be almost completely offset if tree side vegetation was restored across the catchment.
We also found that blackfish could go extinct under a wide range of possible future climatic conditions. This means that blackfish are highly vulnerable to extinction, and hence we must focus efforts towards restoring their habitats.
To achieve the highest chance of blackfish survival, we recommend the complete restoration of the riparian zone and exclusion of grazing animals such as cattle, which will mitigate the impacts of warming stream temperatures and the degradation of riparian zones.
This work appeared in Aquatic Conservation: Marine and Freshwater Ecosystems