The campus lake is the largest plastic-bottomed lake in Europe. The decision by Sir Andrew Derbyshire and Stirrat Johnson-Marshall to give the university a lake had two motivations: one, to give the university a distinct image and identity while also creating areas to foster community; and two, more practically to create a drainage basin for the relatively flat agricultural site as it was feared the construction of the new buildings would increase the risk of flooding. The lake has attracted a large population of wild and semi-wild waterfowl, including greylag, Canada, barnacle and snow geese, coots, moorhens and large numbers of ducks, including mallards, tufted duck, and common pochards. There is also a growing population of black swans and a few great crested grebe. Herons have also been sighted on the lake. The southern end of the lake has been established as a bird sanctuary. Fishing is permitted in season, on purchase of a licence.