Anyone interested in sand dunes was in for a treat last month. The Mellieha council and UNESCO linked up to host a free half-day educational seminar organised by Nature Trust. Participants learned how dunes are formed and were shown examples of both protected and eroded dunes around the Mediterranean.
Louis Cassar of the International Environment Institute, author of a book on sand dunes, spoke on dune dynamics and the lessons that could be learned from other coastal areas in the Mediterranean.
Sand dunes form when wind-driven particles of sand slide and roll across the beach or foredune, colliding with larger grains, ricocheting into the air to be picked up by the wind once again. It is the lighter grains that are blown furthest inland and transported to the resting zone or stable dune.
Pioneer vegetation on a newly formed dune is highly sensitive to disturbances. The natural population of flora struggles to take root and establish itself. A lowering of the fresh water lens in a dune could make it easier for alien species to move in and take over.
Most dunes in Malta are reduced to the foredune as the back has been taken up by agriculture or development. Ramla l-Hamra is considered to be possibly the best dune site in the Maltese Islands and has suffered the greatest impact.
Modification of landscape, agriculture, terracing and dams all mean that less sediment is reaching the beach. When developments disrupt the spatial association between the beach and the dune it is the beginning of the end. Case studies in Italy and Tunisia showed how poor dune management had led to beach erosion.
Coastal dunes depend on an abundant supply of sediment. This can originate out at sea and be transported and deposited by strong onshore winds. Water courses also contribute to the life of a dune by bringing material to the shore from inland. Both factors were originally present for White Tower Bay, the area of study and an ongoing restoration project between MEPA and Nature Trust.
Dune management
Alan Deidun, Coastal Habitats Conservation Officer for Nature Trust, reported on restoration measures at White Tower Bay, one of the last of 32 beaches originally supporting dune systems. Now there are only five left and they take up a total of just 25 hectares between them.
This particular dune is more rich in species than the larger dune at Ramla l-Hamra in Gozo. Reduced to a quarter of its size compared to a few decades ago, the dune at White Tower Bay must be saved before it disappears altogether.
Following constant requests from Nature Trust since the 1980s for the area to be scheduled, the need for conservation was finally recognised in 1995 when all sand dunes were granted status as Areas of Ecological Importance (AEI) by MEPA.
More recently a committee has been set up for the rehabilitation of the White Tower Bay dunes which brings together the Mellieha council and Nature Trust with the Environmental Initiatives Partnership Programme within MEPA. Although not represented on the committee there is contact with the association of boathouse owners as stakeholders in the project.
Until last year parts of the dune were still being used as a car park. The existing road cuts through the dune and is expected to be rerouted as part of the Marfa Action Plan.
Camping has disturbed the dune system's vegetation leading to stunted growth. Fifty African tamarisks which once grew in the bay area were chopped down by government workmen. Increased use of fertiliser on fields further up the valley has had an impact on the dune. This is evident in the spread of nitrophilic species which become rampant at the expense of other dune life.
Improperly managed beach cleaning activities have also taken their toll. The Malta Tourism Authority likes to see tidy beaches with posidonia sea grass collected and removed. On the other hand the dried sea grass is beneficial to maintaining dunes as it forms sandwich-like layers.
Posidonia wracks, the natural banks of dead grass piled up on the shore, form a popular haven for a myriad of organisms between the land and the sea. Many species are so specialised they can only live in the humid habitat of posidonia mounds. Cleaning of the posidonia sea grass which starts in late April could be done manually with some of it being moved back to feed the dune.
While the beach comes alive with human activity in summer it is the worst time of year for dune life. Emergency measures are being taken which, if succesful, will lead to more permanent steps towards conservation. It was planned to put up metal bollards and a chain which would not interfere with sand reaching the dune and have minimal visual impact. Unfortunately vandalism has struck. The chain was cut and an educational sign removed and used as a goal post.
Restoration will include relocation of the road and beach dwellings and a restriction on agriculture in the valley to help terrestrial sediment reach the dune. Measures are to include the manual removal of alien species such as Cape Sorrel (haxixa ngliza) and an attempt to decrease night-time lighting since sand dune fauna are mainly nocturnal.
A buffer zone should be declared all around the sand dunes. New colonisation on the beach part of the dune is a sign that the habitat is slowly returning to health.
Darrin Stevens, an officer with the Biodiversity and Nature Protection Unit within the EPD at MEPA, gave a presentation on the rich heritage of plants found growing on sand dunes.
Today we are left with only the remnants of dune systems which were present up until 20 years ago in 14 different localities. Now only six of these can be seen in Malta, one at Santa Marija Bay in Comino and Ramla l-Hamra in Gozo.
Dune species have developed internal mechanisms to cope with the harsh conditions. They are able to survive because they have adapted to tolerating high salinity. The sand may hardly be visible on a dune which is "fixed" or kept in place by vegetation. Often these have been taken over by agricuture or development.
White Tower Bay displays some fixed dunes which house the only population of endemic Maltese Sand Broomrape. Coast Spurge is a rare species of international importance which has recently died out at White Tower Bay but persists at other dune localities.
Other Mediterranean species such as the Sand Star Thistle or Sand Crosswort are missing on Maltese dunes or were here once but have not been seen for over a century.
Trees, reeds and dunes
Examples of coastal dune woodland remnants are seen at Ghadira, Ramla l-Hamra and Santa Marija Bay in Comino. Alien species of French tamarisk were planted at Ramla il-Hamra in the 1960s. The young African tamarisk tree (bruka) resists smothering and is able to resprout when buried by sand.
While there is much emphasis on afforestation these days there are concerns that the wrong type of tree planting would be damaging for the dunes. The dune remnants at Ghadira and Gnejna require some active management and reintroduction of vegetation chosen to encourage a healthier dune habitat.
The invasion of dunes by alien species of reed is a problem. Previously the reeds were managed by farmers but in cases where they have been abandoned they run riot on the dune and squeeze out dune natives. Recolonisation of dunes with Mediterranean reeds would have to be carried out with great care.
Other alien invasions smother the dunes, mostly the flowering South African succulent Kaffir Fig and grapevines. Landscaping with Washingtonia Palms and Agave at Golden Bay has not been particularly sensitive with regard to the dunes there.
Sea spurge, once common at White Tower Bay, has disappeared and is now only found in Gozo. The prickly Sea Holly is rapidly declining, threatened by cleaning activities and illegal clearings mostly by tourists who are unaware of its value on the dune.
Marram grass, well known as a dune builder because of its expansive root sytstem, once grew at White Tower Bay. The dune grassland was torn up by bulldozers in the early 1980s as part of an acacia planting scheme and is now extinct from the Maltese Islands. The suitability of the grass for the conditions at White Tower Bay, a fixed dune, is debatable since the grass needs a high degree of mobility.
The Sand Carrot is another grass which once grew at the bay but is no longer found there. It was last recorded in Gozo. Although it appears to be extinct there are hopes that some seeds might still be present in the sand.
A management plan is being drawn up for the White Tower Bay dune. The ideal would be to have technically comprehensive management plans in place for all the dunes and surrounding valleys. "If we block or obstruct the valleys we will destroy our sand dunes," concluded Mr Stevens.
A spin-off from large development projects is compensating for some of the damage being done to natural and historical heritage, continuously under pressure from expanding development. This goes by the name of planning gain.
Senior Planning Officer Kevin Mercieca spoke on MEPA's Environmental Inititatives in Partnership Programme (EIPP). He explained how MEPA seeks funds through planning gain which generates projects while mitigating or compensating for environmetal impact.
Partnerships are formed with non-governmental organisations (NGO's) such as Nature Trust and local councils.
A planning gain of Lm200,000 for the L-Ahrax tal-Mellieha area is available and a heritage trail taking in sites of interest is planned. The dunes will offer a natural habitat feature along the route. Specific funding for the dunes will be identified once a management plan for the dunes is in place.
Dune animals
Professor Patrick Schembri, marine biologist, lecturer at the University's Department of Biology and scientific adviser to Nature Trust, introduced seminar participants to the creatures living in and around coastal dunes.
There is much more animal life in and on a dune than appears at first sight. Dune species fall into the category of being rare because their habitats are rare yet the dunes are rich in life.
Life on a Maltese sand dune comprises no fewer than 15 species of ants, 11 arthropods (crickets, scorpions, spiders, wasps) as well as butterflies, preying mantis, beetles, skinks and in Gozo a rare shrew. A rare snail is found only at the dunes of Ghadira and Ramla l-Hamra. White Tower Bay is home to an extremely rare wasp which is found nowhere else in the world.
There are nematode worms, crustaceans, springtails and a whole set of microscopic species that are not known at all. Beachhoppers demonstrate a talent for orientation by sun or moonlight offering great prospects for further study of this branch of biology.
Nature Trust president Vince Attard said that the environment organisation was collaborating with MEPA and the Mellieha council. Mellieha mayor John Buttigieg said the council had been active on the enforcement side, organising inspections by local wardens.