Zona fil-Bahar fil-Grigal ta’ Malta

Name of Site:  Zona fil-Bahar fil-Grigal ta’ Malta 

Year of designation: 2012 

Area [ha]: 15519.4 

Annex 1 Protected Habitats:

  • 1110 Sandbanks which are slightly covered by sea water all the time
  • 1120 Posidonia beds (Posidonion oceanicae)
  • 1170 Reefs
  • 8330 Submerged or partially submerged sea caves

 

 Annex II protected species:

Gibbula nivosa

  

Importance:

This area hosts the largest variety of Posidonia sub-types when considering the marine sites selected to form part of the Natura 2000 Network, with the representativity of each being considered superior. The subtypes present in this site are the following: – Posidonia settled on matte, whose meadows are normally continuous and having a high density; – Posidonia settled on rock, showing a reticulate distribution of dense strands; – Posidonia settled on sand, with continuous beds generally showing low densities and variable percentage cover; – Mosaic morphology, intermixed between Posidonia oceanica, Cymodocea nodosa and coarse sand, showing a reticulate structure; – Ecomorphosis of ‘barrier reef’ Posidonia meadows. The Posidonia meadows within this site are also known for a high degree of connectivity, as well as percentage coverage. From the data available through a Posidonia Baseline Survey carried out in 2002, it is evident that the Posidonia meadows in various parts of this site are very abundant and healthy. They are dense and show a high degree of shoot density, particularly in White Tower Bay, which appears to host probably the highest shoot density in the Mediterranean. The site is also known for the deepest records where Posidonia grows, namely off the south coast of Comino. However, in some areas within this site, such as at Mistra Bay and at Mellieha Bay, the beds are showing signs of regression, especially as a result of anthropogenic activities. Sandbanks, formed by associations of Cymodocea nodosa are also present within this site. The following subtypes are present: – sandbanks with associations of Cymodocea nodosa on well-sorted fine sands; – sandbanks with associations of Cymodocea nodosa on superfically muddy sands in sheltered waters; – facies with Cymodocea nodosa occurring within coarse sands and gravels with more or less mud. As part of a survey carried out in 2002, reefs have been identified within this site, occurring on hard beds and rocks. The following subtypes occur within this site: – reefs with associations of Dictyopteris polypodioides; – reefs with associations of Halopteris scoparis and Padina pavonica; – reefs with associations of Flabellia petiolata and Peyssonnellia squamaria; – reefs with associations of Cystoseira spp. Partially submerged caves are also present, mostly located along the coast of Comino. No quantitative data is available for this habitat type. Amongst the important species within this site is Lithothamnion minervae, a species which has been included in national legislation as a plant species of national interest whose conservation requires the designation of Special Areas of Conservation. Gibbula nivosa, which is considered as the only endemic marine mollusc of Malta, and is listed as having a vulnerable status and a restricted distribution within Maltese waters, is also present within this site. Gibbula nivosa has been found on Posidonia oceanica leaves and under stones.