Habitats of the Maltese islands (17)

The pounding of waves along the shore poses an interesting challenge to organisms which live in what is known as the mediolittoral zone. This is that part of the coast which covers both submerged and non-submerged areas and may be as large as 10cm to 150cm.

The activity and behaviour of several of the species in this zone is actually related to changes in water level.

For instance, some mobile organisms migrate to deeper water when prone to dehydration or heat stress. Others, especially sessile ones, that is, those that are not free to move about from one location to another, become active only when covered with water.

Most of the fauna found in this zone adopt various shapes to break waves, otherwise they can be physically damaged.

For instance, limpets (mħar) have a characteristic cone-shaped shell, which together with the powerful suction of the foot, allows the animal to survive even in the presence of waves.

Species present within this zone vary according to extent of submersion, such that we can possibly distinguish the upper, middle and lower mediolittoral. In rocky shores, organisms in the upper mediolittoral zone include barnacles, limpets and microscopic blue-green algae. In the mid-mediolittoral zone, large algae become evident. In the lower mediolittoral Coral Weed, known in Maltese as korallina, starts to become more evident.

Should you require more information, please contact nature.requests@mepa.org.mt.

The United Nations declared 2010 to be the International Year of Biodiversity. Malta together with many other countries around the globe is carrying out a number of initiatives to celebrate life on earth and the value of biodiversity for our lives. We are all invited to take action in 2010 to safeguard the variety of life on earth: biodiversity.