The endangered vendace, that has been in Britain since the Ice Age, is in danger of dying out as lakes and rivers warm up because of man made global warming.
To ensure the species survival, the UK's environmental watchdog took eggs from Derwentwater in Cumbria, thought to be the only remaining site where the fish are found in England and Wales.
They then took 25,000 young fish from the hatchery to a cooler lake higher up the mountains of the Lake District, Sprinkler Tarn, to establish a new 'refuge' population that is more likely to survive warming temperatures.
Because the route to the lake is so rocky and uneven, it was impossible to use conventional transport like a 4x4 motorbike or landrover. So, the fish were given a ride during part of the two-hour trek by sure-footed llamas from a local charity. The journey was finished by fisheries officers on foot to ensure none of the smarts were spilt.
Lord Chris Smith, Chairman of the Environment Agency, said British species have to be protected from climate change.
"In addition to the anticipated warming of lakes and rivers, we may also see an increase in the occurrence of extreme weather events such as floods, droughts and heatwaves.
"All of these could have an impact on much of the native wildlife in England, especially aquatic species such as the rare and specialised vendace, so we are taking action now to conserve the existing populations." (read more)