The council is urging visitors and dog walkers to stay away from Ashby Ville Local Nature Reserve due to a potential outbreak of blue green algae in the pond, which could be toxic.
An investigation is currently being carried out. The council is working with the Environment Agency to identify if it is blue green algae.
Blue green algae can increase in water that is nutrient-rich causing algal blooms. These blooms can produce toxins, which can kill wild animals, farm livestock and domestic animals.
People visiting any local nature reserves or parks are being reminded to follow the government’s guidance on social distancing measures and only go out once a day for exercise.