Reference is made to Paul Camilleri's letter (December 31) on the Malta Environment and Planning Authority's policy not to consider the prickly pear as an endemic Maltese plant.

The term "endemic species" generally refers to species which occur within a defined area. Therefore, species which are endemic to Malta can only be found within the Maltese islands. The prickly pear (Opuntia ficus-indica) is not endemic. In fact, it is not even of Maltese origin and had been introduced for its edible fruit. At present, it is also used as fodder and as a windbreak, sheltering other crops in fields.

Contrary to what Mr Camilleri claimed, Mepa recognises that the prickly pear is an important crop plant and that it is a characteristic of the Maltese landscape.

However, Mepa also recognises the fact that the prickly pear is potentially invasive if planted adjacent to natural habitats. This plant has invaded natural habitats such as maquis, screes and cliffs. Such invasive species are detrimental to the Maltese natural habitats since they compete with, and may replace, the indigenous Maltese flora. For this reason, while the prickly pear is tolerated on agricultural land, it needs to be kept away from natural habitats and from cliff areas in particular.

Permit PA 00491/01, to which Mr Camilleri makes reference, concerned development on a site lying close to the cliff edge at Ta' Cenc, Sannat. The vegetation communities present on these cliffs are considered to be of high ecological value and the removal of the prickly pears from this site was requested in order to safeguard the important cliff vegetation communities from such invasive species.

In other cases, where the prickly pears are located within agricultural land and away from important natural habitats, the removal of this species is not requested.