Lady’s Island Lake is among the biggest and best examples in Ireland of a sedimentary lagoon. The site supports an exceptional diversity of plant and animal life including the highest number of lagoonal specialists recorded in any lagoon in the country.
The critically endangered Cottonweed plant survives on the fringing gravel barrier separating the lagoon from the adjoining eastern Celtic Sea. The rare plant is not found growing anywhere else in Ireland or Britain.
The largest mixed colony of breeding terns in Ireland is found on islands in the lake together with a large colony of Black-headed Gulls. The site has one of the highest diversities of breeding wildfowl species in the country and is of high conservation importance.