Rocky shore biotic assemblages of the Maltese Islands (Central Mediterranean) : a conservation perspective

Limestone rocky shores constitute ca 90.5% of the 272km coastline of the Maltese islands. Only some 40% of this rocky coastline is gently sloping and easily accessible. Such shores are heavily impacted with 96% of the accessible coastline dominated by tourist-related or by maritime activities. We characterized the biotic assemblages of lowland Maltese rocky shores and tested the popularly held view that given the scarce variation in physical characteristics, such shores form a homogenous habitat. Belt transects were laid perpendicular to the shoreline from biological zero to the adlittoral zone on seven Coralline Limestone and one Globigerina Limestone shores. Cover (for algae and encrusting species) or population density (for animals except sponges) were estimated using 0.5m X 0.05m quadrats placed contiguously for the first few metres and then at regularly spaced intervals. Overall, 19 faunal and 47 floral species, and 10 faunal and 8 floral species were recorded from the Coralline and Globigerina transects respectively, with 60.8% faunal and 25.6% floral species common to the two substrata. Hierarchical clustering showed that the Coralline and Globigerina transects harboured distinct biotic assemblages and identified an upper shore assemblage dominated by the littorinid Melarhaphe neritoides and barnacles, and a lower shore assemblage dominated by algae and molluscs; a mid-shore transition zone where certain species from both assemblages reached peaks of abundance was present in almost all Coralline and the majority of Globigerina transects. Differences in biota between the two types of shore are most likely primarily related to differences in microtopography and, to a lesser degree, to exposure. It is concluded that in spite of gross physical similarity, Maltese lowland rocky shores are biotically inhomogeneous, making conservation of individual sites much more important than previously thought.peer-reviewe

A case for biological zeros

Most ecological work on rocky shores entails the quantification of species distributions and abundances relative to some convenient and accurate datum point. The most commonly used are tide Ievels and chart data. The problem arises when tides are virtually absent as in most of the Mediterranean Sea or when accurate chart data are not available. In the Maltese Islands there is only one datum point located in the Grand Harbour, Valletta. A number of bench marks and trigonometric stations of various orders are found scattered all over the Islands, but these are not always located very close to the shore so that levelling work from these stations to a particular study site may become quite a laborious task which may exceed the capabilities of most ecologists. Furthermore, some of these marks are old and location data for them are untraceable, while others have turned out to be inaccurate. In fact a project is currently underway by the Mapping Unit of the Planning Authority to recalibrate these stations and to establish new bench marks. A further complicating factor is that different charts make use of different datum points. Thus, while Admiralty Charts use a zero point (Chart datum) which is the level of lowest astronomical tide and the level to which all bathymetric soundings are referred, all heights shown on the official Government of Malta survey sheets use a datum point which is 0.5859m above the Admiralty Chart datum and which is taken to be mean sea level (MSL) for the Maltese Islands. Additionally, there is also a Public Works Department (PWD) datum which is 0.4100m above the AdmiraIty Chart datum. It is not always clearly stated which datum points charts and maps are based on. This state of affairs has resulted in field workers having to resort to some other datum point with which to relate all their data, including the so called “biological zero”. However, this also has its own set of problems.peer-reviewe

National Database on Biodiversity : a tool contributing to a better understanding of the flora and fauna of the Maltese Islands

The National Database on Biodiversity (NDB) project was initiated in 1991 within the framework of the Biological Diversity and Genetic Resources Network of the Malta Council for Science and Technology (MCST), in partnership with the Department of Biology of the University of Malta. This project is concerned with the collection and cataloguing of information on Maltese biodiversity and with making this information accessible to a wide range of potential users in the form of a computer database. In the pilot and building phases of the project, data on the flora and fauna of the Maltese Islands was structured in an appropriate format and a customised database with data entry, editing, management and querying facilities was created using Corel® Paradox® 8; the database currently holds some 450 species records and can be expanded to cover the entire range of MaItese species. The problems and opportunities in setting up such a database are discussed.peer-reviewe

A preliminary report on the marine Macrobenthos and the Demersal fish fauna of the island of Filfla (Maltese Islands, Central Mediterranean)

The nature, distribution, and abundance of the main component species of the supralittoral, mediolittoral and upper infralittoral marine macrobenthic assemblages of Filfla were studied during a series of expeditions to the islet between 1990 and J 994. The demersal fish fauna was censused by direct observation. The distribution of sponges was studied along two 2m-wide belt transects laid along a gently sloping and a steep sloping bottom, respectively. In general, the same type of benthic assemblages as found on other exposed rocky coasts in the Maltese Islands occurred at Filfla. However, at Filfla, the littoral zones were compressed, and species richness and abundance in the littoral and sublittoral were generally low compared to other exposed rocky shores in the Maltese Islands. In spite of the extensive infralittoral sandy bottoms present at Filfla, no sea-grass meadows were encountered. Most of these differences are probably attributable to the high exposure, the extensive boulder shores and submarine boulder fields that surround the islet, and to bottom turbulence. Large differences in species composition and abundance of sponges were found between the two transects. Crambe crambe and Agelas oroides were the most abundant sponges on the steep bottom, while Sarcotragus spinosula was the most abundant species on the more gently sloping one. Compared to that of mainland sites, the demersal fish fauna of Filfla was impoverished in terms of both species richness and abundance.peer-reviewe

An innovative sand dune restoration project from Malta

Sand dunes arguably qualify as the most endangered natural habitats in the Maltese Islands due to the small size of the dunes, the low proportion of sandy shores (just 2.4% of the entire islands‟ coastline), the intense human impact, and the lack of public awareness and information about these ecosystems. Out of 32 areas known to have harboured some sort of natural sand dune flora, only five localities now support dunes with a relatively intact characteristic dune vegetation. One of these, the dune at White Tower Bay was earmarked for a dune restoration project since this is the best-preserved sand dune system on the island of Malta. Main threats to the White Tower Bay dune include illegal camping activities and parking especially during summer, trampling by humans and off-road vehicles, ill-conceived afforestation schemes, cultivation in the dune‟s catchment area, and huts that abut on the dune. These threats operate even though the White Tower Bay sand dune is scheduled as an Area of Ecological Importance and a Site of Scientific Importance. Restoration of the White Tower Bay sand dune is being jointly undertaken by the Malta Environment and Planning Authority (MEPA) and the NGO Nature Trust (Malta), as part of MEPA‟s Environmental Initiative In Partnership Programme. Restoration includes both short-term (temporary) and long-term (permanent) measures. Emergency measures included the installation of metal bollards joined by metal chains around the dune‟s landwards border to prevent vehicular access to the dune from the road skirting it, as well as the installation of educational signs explaining the importance of the dune and the scope behind the restoration works. Due to consultation with stakeholders and their involvement from the onset, it was ensured that conflicts were minimized. The permanent restoration measures will be completed within the next few years. These include the gradual relocation of the huts, closure of the road surrounding the dune, the manual removal of alien flora, and the planting of Ammophila littoralis (marram grass) – a stabilising pioneer species of foredunes that is now extinct from the Maltese Islands – along the seaward margins of the dune. In addition, the complete removal of seagrass wrack from the beach will be discouraged. Special emphasis will be placed on the educational value of the site and on effective enforcement of existing and planned regulations concerning the area through wardening. This restoration project is locally (and perhaps regionally) innovative for a number of reasons, including the extensive and ongoing consultative process with all stakeholders, the emphasis on the educational value of the site, the basing of restoration measures on sound scientific research, and the inclusion of a monitoring programme to assess effectiveness of the interventions and to fine-tune these as the need arises. This initiative can serve as a pilot upon which other habitat restoration projects may be based.peer-reviewe

Biodiversity conservation and utilisation in the Maltese Islands

The Maltese archipelago which occupies an area of c.316km2 consists of the inhabited islands of Malta, Gozo and Comino and several other uninhabited islets and rocks. In spite of their restricted area, the limited number of habitats, and the intense human pressure, the Maltese Islands support a very diverse terrestrial and freshwater biota, with some 2000 species of plants and fungi known, more than 4000 species of insects, several hundred species of other invertebrates, and more than 200 terrestrial or freshwater vertebrates; of these c.80 taxa are considered as endemic. The most characteristic terrestrial ecosystems are those represented by the Mediterranean scrubland, of which the maquis, garigue and steppe are the main types present - evergreen woodlands are all but extinct and only four relict patches occur. Minor terrestrial ecosystems include rupestral, freshwater and coastal communities including sand dunes, saline marshlands and rocky coasts. Marine communities include those characteristic of both hard and mobile substrata. Human impact is significant, and human influence is a key feature of the islands' ecology. In fact, the population density is the highest in Europe and built-up areas have increased from 5 to 16% in the past 30 years. Some 38% is agricultural land and 46% of the area is undeveloped, but even so, no wilderness areas remain in the Maltese Islands. The management practices of the islands include mainly those concerned with agriculture, animal husbandry and herding, and the use of fire, which all proved to be detrimental to the local biota, mainly through habitat destruction, the removal of competing species and the introduction of alien ones, particularly goats, rabbits and sheep. All these human activities have put great stress on the Maltese biodiversity, with a consequent impoverishment of the flora and fauna. Flora and fauna which are directly or indirectly exploited in the Maltese Islands are reviewed. Work on biodiversity carried out by national institutions, government departments, agencies and non-governmental organisations is also outlined. Legislation safeguarding biodiversity is relatively new to Malta. Prior to the Environment Protection Act [EPA] (1991), and the Development Planning Act [DPA] (1992), legislation mainly protected species due to their associated economic importance. Both the EPA and DPA have permitted the creation of protected areas. The EPA also protects some of the flora and fauna, including some 10% of the endemics. The DPA, on the other hand incorporates the Structure Plan for the Maltese Islands which is a strategic plan meant to harmonise development with conservation. On the international level, Malta is party to the Washington Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) which is implemented locally by means of regulations controlling trade in species of flora and fauna (1992). Malta is also party to the Ramsar Convention, the Berne Convention, the Barcelona Convention, the Convention on Biological Diversity, and the Law of the Sea Convention.peer-reviewe

Final report in connection with MED-ERMIS (Mediterranean Environmental Reporting Monitoring and Information System) MALTA

This report outlines the work that has been carried so far as part of the MED-ERMIS (Malta) project between November 2000 and November 2002. The Sustainability Indicators – Malta Observatory (SI-MO) was established in November 2000 to meet the requirements of the MED-ERMIS (Malta) project. The Observatory’s main remit was to conduct research and development work, and to disseminate information on Sustainability Indicators for Malta. SI-MO engaged research assistants, consultants and secretarial staff in order to assist in the execution of this project.peer-reviewe

State of the Environment Report for Malta 1998

All activities of Man have an impact on the local and global environment. It has become increasingly important to gauge these impacts, both because these impacts are becoming more and more significant and also because Man’s expectations have increased more than ever before in the last ten years. Moreover, the aspect of sustainability, that is whether what we are doing today to satisfy our needs will have an impact on future generations, has become an overriding concern. It is therefore important that all decisions are taken with an informed mind. For this to be possible, there must be accurate and accessible information about the state of our environment. Indeed, in signing the Convention on Access to Information, Public Participation in Decision-Making and Access to Justice in Environmental Matters in December 1998, Malta has pledged amongst other things to keep the public informed about the state of the environment. This is precisely the scope of this report, which intends to be one of a series of regular snap-shots of the state of the local environment. Such reports will facilitate a co-ordinated response to be made and eventually will enable trends to be discerned. While the report shows that there is considerable work still to be done in the environmental field, it is nevertheless a milestone towards achieving sustainable development. [preface]peer-reviewe

Detecting low-level sewage pollution using rocky shore communities as bio-indicators

Coastal pollution due to high inputs of organic matter is easy to detect and monitor it is much more difficult in the case of sporadic low-level inputs. Full routine water-quality surveys of large stretches of coastline are time-consuming and expensive. The present study evaluates the suitability of using rocky shore community structure as such an indicator in the Maltese Islands. The rocky shore communities at Xaghra, which is 1.3km south of Malta’s main sewage outfall were sampled. The peculiarities found in these communities suggest that rocky shore biotic assemblages may be useful indicators of low-level sewage pollution, at least under local conditions.peer-reviewe