The Environment Agency is urging people to report potential sightings of dangerous blue-green algae in Cumbrian Lakes.
It comes after sightings of the algae blooming in Coniston, Windermere and other lakes in the county.
What is blue-green algae and why should you report it?
Blue-Green Algae is a group of bacteria known as ‘cyanobacteria’.
It's more common in warm and dry weather - however, it can also come about in periods where there is heavy rain.
The algae poses a small risk to human health if a person comes into direct contact with the water (e.g. while swimming).
It can pose a serious risk to animals such as dogs if they drink or swim in the affected water.
The Blooming’ Algae app will help people to report and record potential sightings of blue-green algae.
It works by allowing you to take a picture of the algae at a specific location - it should help speed the process for warning members of the public and helps manage risks in the area.
Professor Laurence Carvalho of the UK Centre for Ecology & Hydrology said: “If people report sightings via the Bloomin’ Algae app with a photograph, we can quickly check if it is blue-green algae or something harmless, with correct and incorrect reports plotted on an interactive map in the app.”
Bloomin' Algae app users can set up notifications for confirmed blooms in their area.
Blue-green algae can cause stomach pains, vomiting, diarrhoea, and skin rashes - though the risk to people is normally very low as they are unlikely to swallow much contaminated water.
Environment manager at the Environment Agency Jim Ratcliffe said: "Animals such as dogs can, however, be more seriously affected and we would urge dog owners to keep their pets out of the water if they suspect that blue green algae may be present."