Vendace (Coregonus albula) are thought to have been present in the lake for over 11,000 years, becoming trapped there after glaciers retreated.
The species is also thought to be one of the first to have arrived and settled in UK, but has only ever been documented in two lakes in England; Bassenthwaite Lake and Derwent Water.
Scientist Dr Ian Winfield from the Centre for Ecology & Hydrology, Lancaster, who captured the video of the fish, explained that work on the species and monitoring/sampling has been taking place since the 1990's using survey gill nets and hydroacoustics.
The latest sampling (November 2016) estimates there to be around 5000 Vendace adults present in the lake.
Dr Winfield explained that the footage of the fish was captured at the deepest part of the lake, at a depth of around 20 meters.
"The fish needs cold waters and cannot tolerate waters above 15°C. The Vendace therefore retreats to the deepest part of the lake where the water is the coldest," Dr Winfield said, speaking to The Fish Site.
The Vendace also requires high oxygen levels and feeds on zooplankton.
While the species seems to have established itself well in the lake, it is facing threats from two fish species that have been illegally introduced over the last few years. The two species, Roach and Ruffe, may compete with Vendace for food - zooplankton - and eat its eggs, respectively.
Although monitoring and knowledge of the species is growing, there is one thing puzzling scientists - it is why, in the video footage, the Vendace appeared to show aggressive and erratic behaviour towards the perch?
The scientists will now continue their work on the species and hope to catch more footage in the near future.
Take a look at the fast moving Vendace, here:
