The Convention on Wetlands of International Importance, called the United Nations Ramsar Convention, is an intergovernmental treaty that provides the framework for national action and international cooperation for the conservation and sustainable use of wetlands and their resources. It is named after the city of Ramsar in Iran, where the Convention was signed in 1971.
L-Għadira and is-Simar are considered to be two of the few main wetlands in the Maltese Islands. These are designated as Ramsar Sites (apart from forming part of the Natura 2000 network and having other designations). Both these sites are managed on the basis of a management agreement with BirdLife Malta.
Għadira is a brackish coastal pool (once used for salt production) of varying water level and salinity, bordered by a remnant dune. Several rare plant species, salt-resistant vegetation, and a diverse invertebrate fauna, including endemic grasshoppers and wasps, are known from this site. Aphianus fasciatus, better known as the Mediterranean killifish, and which happens to be the only freshwater fish found in the wild in the Malta, is known from this site, where it is found in a relatively good status. L-Għadira is an important area for resting and feeding for numerous species of migratory birds.
Is-Simar is a human-made coastal wetland, consisting of a saltmarsh, a central pool with islets supporting dense salt-resistant vegetation, shrubs, and Aleppo pines. Water levels are maintained by precipitation, run-off, and saltwater seepage through the porous substratum.