Loch Lomond faces "extreme loss" of fish within 80 years, study suggests as heatwaves will see water temperature rocket. Researchers at the European Space Agency modelled the impact of severe climate change on hundreds of lakes around the world, concluding that the length and intensity of heatwaves would increase, with potentially catastrophic implications for wildlife. At Loch Lomond, one of two UK lakes included in the study published in the journal Nature, average temperature rise during a heatwave would increase from two degrees to four degrees, and heatwaves would increase in length from 12 days to 174 days per year. Lead author R. Iestyn Woolway, a research fellow at the ESA, said heatwaves could lead to algal blooms which can threaten the health of humans and animals. "Algal blooms and fish die-offs can render a lake unsuitable for recreational activities which then has a detrimental influence on businesses that cater to them, with a knock-on effect on others," he said. As well as trout and salmon, the loch is home to the rarer powan whitefish, which is a species that is particularly susceptible to temperature changes. Co-author Professor Stephen Maberly, an expert in the impact of climate change on aquatic life, said that a previous heatwave in central Europe in 2003 had had significant impact on the oxygen and algae levels in affected lakes. "It's going to affect the physics, the chemistry and the biology of the lakes, and especially species which are at the edge of their range. Maybe that will push them over the limit," he said.