Greening of the Sea Gives Adriatic States the Blues

Bojana Stanisic Podgorica, Kotor, Dubrovnik, Split, Mljet, Bari, Ancona, Rome and Pisa

A plague of invasive algae is testing countries’ willingness to work together to save their marine heritage and tourist industries.

The pristine waters of the Adriatic have long been the boast of the countries with coastlines alongside it. Azure in colour and much cleaner than the adjoining Mediterranean, they are a major draw for the growing numbers of foreigners holidaying in Slovenia, Croatia, Montenegro and more recently, Albania. With the decline of heavy industry in all, these waters constitute a precious economic asset.

Now they face a new danger. Year by year, an insidious green underwater predator is making its stealthy advance, disturbing the marine environment as it does so and turning pristine sandy and rocky seabeds into thick carpets of waving green fronds.

The state of the once clear waters around the Ligurian island of Elba is a stark warning of what the Adriatic may expect. Formerly home to beds of dazzling coral and molluscs, they were a paradise for divers. “Today, no one goes there for diving,” Professor Francesco Cinelli, a marine biologist at the University of Pisa, laments, peering into the water at the village of Marina di Pisa. “The seabed is covered by a green carpet”, he explains.

Professor Cinelli is talking about Caulerpa Racemosa, an invasive algae that has spread like wildfire in the Mediterranean, and now threatens to do the same in the Adriatic.

The plant is not merely unattractive. Forming dense colonies on all types of seabeds, in both clean and in polluted waters, it transforms the characteristics of its adopted habitat, dramatically reducing the variety and abundance of other underwater fauna. Rapidly growing on all surfaces and in both cold and warm water, it blocks out the sunlight that smaller marine plants need, causing their death.

In addition, the algae releases alkaloid substances that kill all other organisms in its vicinity. By destroying rival flora as it covers the seabed, it also impairs the survival of fish and molluscs that feed on other underwater plants, or which require bare sand or rock as a habitat. Sole and spider fish are especially endangered, as they require sandy seabeds.

“When Caulerpa covers the seabed like a carpet, these species lose their natural habitat,” says Ante Žuljević of the Institute for Oceanography and Fishery in Split, Croatia.

The spread of the algae into the rest of the Adriatic and the Mediterranean, therefore, will deplete economically viable edible fish stocks as well as deter divers and tourists. Seas renowned for numerous fish species and for the beauty of their underwater landscape could turn into monotonous underwater deserts.

Scientists say if governments in Italy, Slovenia, Croatia, Montenegro and Albania fail to take concerted action to eradicate the scourge, it is likely to spread beyond their control. Yet in spite of the serious nature of the threat, governments in the Adriatic region have so far shown no sign of cooperating among themselves, nor have they actively sought advice from other EU countries, such as France, Italy and Spain, which have already faced this problem and worked together to limit the damage.

Coming to a sea near you

The existence of Caulerpa Racemosa in the Mediterranean was first noted some 80 years ago. A tropical species originating in the Red Sea, it came through the Suez Canal in the early 1930s and gradually took over more than 50,000 hectares of the seabed. Designated by the European Commission as a serious threat to marine biodiversity some ten years ago, it has since advanced across the Mediterranean and into the Adriatic with growing speed.

After its initial appearance off Libya about 20 years ago, it moved to the coastal waters of other Mediterranean countries on sea currents. Man inadvertently carried these marine hitchhikers on the bottoms of ships, their anchors and on fishing nets and diving equipment. Each time an “infected” boat anchored or discharged ballast water at a port of call, algae fell off and found new habitats.

Arriving later to the Adriatic, Caulerpa Racemosa has, in the last three years alone, spread in Montenegrin waters from two to eight locations. The biggest infested area is around the Luštica peninsula at the entrance to the Bay of Kotor, where the algae has spread over two square kilometres. Two new outbreaks were recently spotted there and in the immediate vicinity of the resort of Budva, south of Kotor. By late August, it was estimated that the algae covered a total of over four hectares of the Montenegrin seabed.

In Croatia, the scourge is worse. After first appearing near the Pakleni Otoci, a group of islands in central Dalmatia, a total of 54 locations have become infected. It was also reported recently in the waters off the island of Mljet, a national park whose blue seas are an important attraction for visitors.

The fact that the algae has no natural enemies in the Mediterranean has assisted its spread. So has insufficient awareness of the seriousness of this problem. Long after it appeared, France, Italy and Spain failed to take much notice, and by the time they realised the nature of the threat, it was too late.

Today, the waters off Elba are not the only ones in the Mediterranean suffering massive infestation. Much the same has happened to the seabed off Monaco, on the Cote D’Azur, according to Thierry Thibeau, a researcher from Nice University. There, the algae has driven out rival flora and fauna. “Divers don’t want to dive around Monaco since there is only a green carpet of Caulerpa there now,” Thibeau maintains.

The fightback – it hasn’t really begun

While the total eradication of the algae is no longer a practical proposition, scientists believe its spread can be slowed through the concerted application of European directives prohibiting anchoring, fishing and diving in infested areas.

Belated awareness of the problem has, meanwhile, scared the Mediterranean countries into working together to protect maritime areas of key importance in terms of biodiversity, fishery and tourism development. Spain, France and Cyprus are undertaking joint research projects, and setting aside money to investigate eradication strategies and map the extent of the problem.

There is no sign of similar cooperation against the algae among Balkan countries along the Adriatic coast, which experts attribute to a lack of administrative capacity, shortages of money and a failure to harmonise domestic legislation with European law.

Montenegro’s parliament, for example, has yet to pass even basic necessary regulations on marine management in the form of an environmental protection bill, though one is supposed to be enacted by the end of this year.

National institutes for marine biology of the Adriatic region started exchanging information on common problems a couple of years ago, but governments have not kept pace. They have not declared the eradication of Caulerpa a priority, for example, and show no signs of doing so.

Reasons for the current lack of political cooperation among the countries in the region range from political divisions to an absence of a real awareness of the magnitude of the problem. The wars in the Balkans in the 1990s have also had a lasting, negative, impact, slowing the information flow among the individual states, especially between Montenegro and Croatia, while Albania is only just emerging from years of self-imposed isolation.

Europe urges common action, however. “Coordinated action of states affected or likely to be affected by Caulerpa is strongly recommended, particularly in terms of adopting common strategies,” the Council of Europe recommended, as far back as 1995.

More recently, the UN’s development arm, UNDP, urged all Western Balkan states to increase their commitment – and adopt a more concerted approach - in tackling environmental concerns generally. In a report, issued this October, it made an explicit link between progress in this regard and further European integration.

Scientists working on the algae threat agree the Adriatic states cannot tackle the problem in isolation. Roberto Danovaro, of the Marine Science department at the University of Marche, in Ancona, Italy, says regional and European cooperation is essential. “It would be very stupid to discuss marine issues solely at the local level,” Danovaro says. “We must have a common policy concerning the sea.”

Representatives of the non-governmental sector agree. “It would be pointless for one of these six countries to address the problem if all the others don’t do the same,” says Maria Rapini, of the Rome-based environmental group, Marevivo. “Perhaps they might eradicate it, but it would only be temporary, as it would return again, say, from Albania or Montenegro.”

Gianni Guarieri, a former advisor on international relations to the Italian environment ministry, also believes that “the Adriatic requires joint projects”. He highlights the need to create jointly protected marine reserves. “Every [coastal] municipality should designate one of these zones,” adds Guarieri. “They must possess biological wealth, and be attractive, so that the population living in the vicinity can profit from this.”

Montenegro’s Riviera under threat

The Veslo Cove, at the entrance to the Bay of Kotor, is widely seen as the pearl of the Montenegrin coast – a key asset to the burgeoning tourist trade on which the newly independent republic increasingly depends for its future prosperity. But the underwater situation is alarmingly similar to that around Elba, according to Vesna Mačić, of the Montenegrin Institute for Marine Biology. She says Caulerpa is already wiping out local molluscs and other algae.

Accurate data on how the algae is changing the biodiversity of Montenegrin waters does not exist because Montenegro’s maritime experts have no data on which species inhabited the waters before it appeared.

The government has invested only tiny sums in resolving the algae problem - 10,000 euros over the last three years. By comparison, Croatia has earmarked around 135,000 euros each year for the same purpose while France spends 50,000 euros a year on mapping the extent of Caulerpa’s spread alone.

Montenegro justifies the meagre sum it has made available for research by claiming that the area infested with the algae is not yet alarming. According to Siniša Stanković, of the environmental department of the ministry of tourism, there is also little point in throwing money at an ineradicable problem. “If we knew what the methods were for the eradication of the algae, no one would be saving money on this,” he says. “But all the currently known methods can do is limit its proliferation.”

Montenegro is a small, relatively poor country, and finds it politically hard to justify allocating funds for environmental protection from its limited budget. More questionably, though, it takes no real advantage of EU pre-accession funds made available for this purpose - according to Stanković, this is because it lacks the administrative capacity to prepare and implement such projects in keeping with European standards.

Stanković says the Montenegrin government plans to make up for lost time by taking part in a new marine protection project backed by the World Bank, the Global Environment Facility, a mechanism that helps developing countries fund projects that protect the global environment, and UNEP/MAP, a UN environmental programme for the Mediterranean.

“We’ve earmarked 150,000 dollars [approximately 107,000 euros] for the purpose of underwater sea life protection over the next five years,” Stanković claims, adding: “Part of the money will be spent on Caulerpa eradication.”

The Montenegrin state company, Morsko Dobro, which manages the republic’s marine zones, has also taken the first steps towards alerting the public of the danger posed by the algae, by printing and distributing brochures. Aleksandra Ivanović, who works on the campaign, says that since 2005, the company has also funded monitoring activities and attempts to prevent the spread of the algae in the waters around Budva using foils that block the sunlight the algae need to live.

But the sums it has spent on these activities so far are minimal at only 5,000 euros.

Whatever happened to the “ecological state”?

Despite its increasingly rapid integration into the EU, Montenegro has done surprisingly little to put into place laws to combat invasive marine species, even though they constitute an important part of the Union’s environmental law. The fact that Brussels recognised the issue as a priority in its Sixth Environment Protection Action Plan, adopted in 2002, shows how concerned it is with this problem.

In its communication of September 2006, Halting the Loss of Biodiversity by 2010, the European Commission’s Environment Protection Directorate also identified this as a key area, saying action needs to be taken to halt the spread of alien species.

It is currently drafting a strategy to solve the problem. “The Algae Caulerpa Racemosa has been recognised as a serious threat to marine biodiversity,” says Lenka Karova, of the Commission’s Environment Directorate. “This strategy is intended to reduce the detrimental effects of invasive species on European biodiversity in a sustainable manner.”

She went on to say that research conducted as part of the project, Streamlining European 2010 Biodiversity Indicators, SEBI2010, listed Caulerpa among “the worst invasive species threatening European biodiversity”.

Although Montenegro is an “ecological state”, according to the first line of its own constitution, the country has neither ratified the 1976 Barcelona Convention for the Protection of the Mediterranean Sea against Pollution, nor signed the 2003 Bern Convention on the Conservation of European Wildlife and Natural Habitats.

Siniša Stanković promises that the Barcelona Convention will be ratified by the end of the year and says “this law, and particularly the protocol on protected areas appended to it, will meet necessary preconditions for solving the Caulerpa problem”. But it all comes late in the day. All Mediterranean states are already signatories to the Barcelona Convention, and so are most of Montenegro’s neighbours. The Croatian parliament passed a law on implementation of the Barcelona Convention back in 1996.

Apart from Bosnia and Herzegovina, which has only a tiny coast, Montenegro is also the only Adriatic state that has not signed the Bern Convention. “It makes no sense to boast that we’re an ecological state given our attitude towards the sea,” Vesna Mačić says.

Montenegro is also an exception, compared to other Mediterranean states, in having no officially designated protected seas. According to EU directives and conventions, every state is obliged to have several national parks or protected marine areas and to adopt legal regulations to protect them from pollution and invasive species.

Sea reserves are to be protected by law from unauthorised anchoring, diving and fishing. Italy, for instance, has 27 protected marine areas and the objective, says Maria Rapini of Marevivo, is to increase the number to 50 in next few years.

“When we ratify the Barcelona Convention, we’ll be under obligation to declare protected marine areas,” pledges Ana Pajević, of Montenegro’s ministry for tourism. “We plan to protect 10 per cent of the total marine area in Montenegro.” But for the moment, these are just goals.

Scientists show the way

While politicians from the countries in the region have done little to cooperate on tackling the threat to their common marine heritage, scientists from the various countries are busy exchanging information. “The sea has no borders,” Mačić says. “If we want to preserve it, we must all work together. All those dealing with marine issues know there can be no borders there.”

The Institute for Marine Biology in Kotor is collaborating with the Institute for Oceanography and Fishery in Split, the Institute for Marine and Coastal Research in Dubrovnik, Croatia and with the Laboratory for Marine Biology of the University of Nice, in France.

The Kotor institute’s staff is proud it initiated a joint project on their border marine area in company with their Croatian colleagues shortly after the wars of the 1990s. “Collaboration in the field of marine protection is a good model for reconciliation between former foes in the war,” Mačić suggests. Her counterparts in Split and Dubrovnik echo this conviction.

But the wars in the Balkans have left lasting consequences and scientists admit that it will take more time before full scientific cooperation is restored. “Five years ago, the German government wanted to fund a project on dolphins which Croatia would implement together with Montenegro,” notes Vlado Onofri, of the Dubrovnik Institute for Marine and Coastal Research.

“But owing to the antagonistic political positions of both countries, we failed to establish cooperation.” He adds: “Wars inhibit exchange of information, particularly in the heads of politicians and statesmen, and they are the ones holding the purse-strings.”

Osvin Pečar, director of Mljet National Park, agrees that the problem is the politicians. When it comes to scientists in the region, “[W]e’ll cooperate with everyone if our interests are involved,” he says. “But if you get your money from governmental structures, then it’s much more difficult.” Meantime, the unique beauty of the Adriatic seabed remains in serious danger from this mobile predator.

Seaweed and snails – unlikely allies

Can anything be done at this stage? There are some faint hopes of an environmentally friendly solution to the problem of the spreading algae. Scientists highlight the importance of the Posidonia variety of seaweed, for example, which can create a natural barrier to the spread of Caulerpa.

But this is only possible when the Posidonia colonies are large and healthy. “If Caulerpa destroys the Posidonia, the fish in that area will leave, and the coastal zone will suffer from erosion,” notes Professor Cinelli of Pisa University.

Another proposed “biological” solution is the introduction of a tropical snail whose staple food is Caulerpa. The snail in question inhabits seas around Australia and its introduction to the Mediterranean would help solve the Caulerpa problem in the best possible manner, according to Ante Žuljević of Split.

Scientists are also investigating whether the proliferation of Caulerpa can be halted by covering infected locations with foils, although many argue that this method does not yield good results. “Covering the algae with foils, or injecting poison, is like chemotherapy – it destroys not only the tumour but the organism as well,” Onofri says. “Poison injected to eradicate the algae will also kill micro-organisms living in the vicinity.”

Other measures aimed at controlling the spread of the algae, meanwhile, collide with the demands of the tourism industry.

One method recommended by scientists is to prohibit boats from anchoring in areas where Caulerpa is present, or where there are colonies of Posidonia, as these may be destroyed by anchoring, clearing the way for the algae. “A cruising liner with an anchor weighing several tons can uproot Caulerpa and scatter it all over the seabed,” Onofri says.

He says a ban on anchoring is certainly needed in the Dubrovnik area, where big ships arrive daily. But the economics of tourism make this very unlikely. “If we prohibit anchoring, there will be a detrimental economic impact,” he admits.

As far as local residents are concerned, though, there would be no love lost. “The tourists that come with these boats do not spend any money in our cafés or restaurants. They have everything on their floating city”, Ljuba, a café owner says. “They just pollute our sea and air, bring some strange plants on their anchors and then leave. It’s better they don’t come at all”, she added.

Osvin Pečar agrees that something needs to be done, but knows this will be hard to achieve. “A prohibition on anchoring in coves is directly opposite to the needs of nautical tourism,” he says. “About 25 per cent of nautical tourists come to Croatia only because anchoring is allowed everywhere.”

He and Onofri hope for a compromise solution in the form of large buoys, to which ships could anchor themselves without coming into direct contact with the seabed. Scientists, NGOs and governments also urge people diving, anchoring or fishing not to throw Caulerpa back into the sea if they pick it up. If people cannot halt its spread, they should not at least help its propagation.

Meanwhile, Onofri warns that the unchecked spread of Caulerpa will have serious economic ramifications for all the Adriatic states in the near future. “In a couple of years, the sea will be blue on the surface, but green on its bed,” he says, pointing at the small island of Lokrum lying off Dubrovnik, a seaside paradise now “occupied” by the insidious algae.

“Caulerpa is ‘ethnically cleansing’ the sea,” Onofri says.

Fellow Bio


Bojana Stanisic

Bojana Stanisic from Podgorica, Montenegro, is editor and journalist for TV Vijesti and founder of web-portal Evropski Reporter