DRAMATIC CHANGES IN ADRIATIC ECOSYSTEM: Unwanted Deep Sea Guests

The so called Tumour of the Mediterranean- a noxious seaweed, keeps spreading along the coast of Montenegro, venomous fish end up in fishing nets, and by a stroke of luck, they still haven't made it to the dining table, giant crayfish pop up, huge bluefish and dangerous mako sharks are on the horizon... while on the other hand, the authorities have no clue how to respond- for the time being    

The Tivat based St. Mark fishing vessel was gliding the calm open sea a few miles south-east of the Bay of Kotor. As the crew was getting ready to launch a dragnet into the deep, it noticed a commotion some two hundred metres away. A huge fish was locked in a death grip near the surface and its reflection gave off the position. The fishermen sped to the spot and found a dying greater amberjack whose lower half was chopped off. The unidentified 'villain thing' had a half a metre jaw mouth opening.

Some 46 new species of sea plants and animals have been confirmed in the Adriatic in recent years. Nonetheless the number is not final. Among them are some dangerous species like lionfish whose fin rays can be fatal to humans if not treated. Furthermore hazardous mako sharks are frequently spotted closer to the shore than before. The local fishermen have had a growing number of encounters lately with the species that inflict damage to their equipment or spoil the catch. They may have adverse effects on tourism as well.

New animal and plant species arrive due to global warming and increasing marine traffic. Vessels from all over the world carry tiny stowaways on their hulls and in their ballast waters- larvae and full grown fish, molluscs, algae and other creatures.

So far, the government hasn't tried to lay out a plan on how to deal with this global issue besides drafting a few papers. Furthermore there is no systematic marine ecosystem monitoring, especially when it comes to the spread of invasive and hazardous species like Caulerpa Cylindracea algae which many call the Tumour of the Mediterranean. According to Montenegro Investigative Reporting Centre (CIN-CG), it spreads unchecked and takes over seabeds along Montenegro's coast.

Dr Aleksandar Joksimovic is an ichthyologist and until recently on Montenegro's expert team that deals with Chapter 13- fishery of the EU accession talks. He points out that the Adriatic's temperature has risen by 0.6 degree Celsius in the last century. “That doesn't seem to be much, but even small temperature shifts combined with other physical and chemical parametres of the seas and oceans cause substantial changes in the living world. We can certainly say that the temperature shift has tropicalized the Adriatic Sea. The best example of that are new organisms which are bio-indicators of the habitat changes. As a consequence we have 46 new plant and animal species” emphasizes Joksimovic.

Dangerous Lionfish Fin Rays

The majority of non-native (allochthonous) species are unable to adapt and thus they disappear. A few manage to intergrate into the existing native species without causing any serious harm. Nonetheless, some species quickly adapt as they have no natural predators. Consequently such communities exponentially grow and push out native (autochthonous) species. As a result, biodiversity is on the decline, the food chain is disrupted and the whole ecosystem is affected. Invasive species put the ecological balance at risk for they threaten autochthonous fish and other organisms by feeding on them or kicking them out of their habitats. Arrivals of allochthonous fish contribute to social and economic changes. Some bring economic benefits while others pose a threat and harm the fish and fishing trade.

“We can already claim with certainty that about ten new species of fish and crayfish have fully accommodated in the Adriatic”- says Dr Mirko Djurovic, director of the Kotor based Institute of Marine Biology (IMB) in an interview with CIN-CG.

The Institute has been monitoring the impact of invasive species in the Adriatic for awhile. Its 40 experts (of whom 12 have doctoral degrees) and 7 post-graduate students, work together with colleagues around the region and with those further abroad to draft a new biological profile of the Adriatic. They published the 'Allochthonous Species of South Adriatic East Coast' monograph back in 2014 together with the Institute for Marine and Coastal Research of the University of Dubrovnik and the Institute of Oceanography and Fisheries in Split. Nevertheless the monograph is already due for an update given the arrival of new unwanted guests. Kotor's IMB also collaborates with marine biodiversity experts in Albania and Italy.

'Various satellite recordings indicate that the Adriatic in early July was very warm. Even over here ( the south of Adriatic) the surface temperature reached 26-27 degrees Celsius, which is pretty high at this time of the year. The sea temperature is very often the trigger for organisms' behavioural changes, like reproduction, feeding, etc. Hence there's a growing presence of the so called termophilic species which like warmer seas. “That's primarily the case with fish and crayfish” says Djurovic. He stresses that when it comes to the new species here, the lionfish, a native of the southern Pacific and the Indian Ocean, is considered a potential threat.

“The presence of this fish has been confirmed in the Adriatic. It is highly venomous and its toxin in the fin rays can be fatal to infants and older people” warns Djurovic and adds that certain jellyfish turn up in big numbers occasionally and that may affect tourism.

'Montenegro as a tourist destination is appealing because of the attraction of our sea. However, with each year we have more invasive species. We'll see how our tourism and fishery stand the test of time. “The warming up of the sea is also something to count on. It is hard to make any forecast right now”, says Djurovic.

The Mediterranean Tumour keeps spreading

Some of the invasive species like 'the Tumour of the Mediterranean' are harmful to the environment although humans are not directly affected. This algae was first noticed in 2004 when it covered only a few square metres of seabed in the Bay of Budva. Now it covers hectares of the sea floor. Experts warn that it will keep spreading as it has no natural predator while science still hasn't found a way to stop its progress. It grows fast and it spreads over seabeds as a carpet thus destroying sea flora and fauna. It is particularly harmful to posidonia sea grass which is essential for marine biodiversity and as such protected by international conventions. The aforementioned algae discharge an alkaloid substance which causes death to surrounding  organisms. It also affects fish, crustacean and molluscs which feed on seabed plants and live in rocks or sand. The areas covered by this algae become 'underwater deserts' rendering the landscape monotonous and poor in terms of biodiversity. It also harms diving tourism as divers seek areas abounding with fish, corals, clams and other creatures. The noxious seaweed Caulerpa has got the upper hand over substantial part of the Pakleni Islands seabed in Croatia in recent years thus slashing scuba diving revenues as tourists used to travel to see underwater walls with its distinguishing gorgonians.

“Upon discovery of Caulerpa near Budva in 2004 we conducted a certain monitoring so we could keep an eye on the algae and its growth” points out Dr Vesna Macic of IMB, the head of its laboratory for benthos and marine protection. Benthos is all plants and animals living at the sea bottom. Macic is the first one in Montenegro who discovered and scientifically examined Caulerpa. Unfortunately,  the Caulerpa database is not up to date as the government discontinued the monitoring (and the financing thereof).

“What we know for sure is that Caulerpa is spreading to more and more places. Earlier it was identified in Budva, Lustica and Donji Grbalj. Now those areas are even more infested with it, both in terms of size and depth. Now the noxious seaweed is present in previously intact areas south of Bar and Ulcinj. It's present at the entrance of the Bay of Kotor, around Dobrec and Njivice. I believe it hasn't spread further inside the Bay, and perhaps the fresh water influx there has something to do with it. Anyway, we can't be completely certain about it without detailed monitoring and research” – explains Dr Macic.

Apart from global climate changes and marine traffic, Dr Macic claims that the Adriatic biodiversity is also harmed by human activity like pollution of the sea, overbuilding along the shoreline, poaching, use of dynamite for fishing and fishing of date-shells. The latter practice is widespread. The Marine Fisheries Inspectorate conducted intense controls of restaurants and shops in August last year and in just ten days it confiscated 325kg of fish and seafood. It also found 25kg of date-shells in spite of the ongoing fishing ban. The date-shells are offered under the table though. In order to supply a single dish of date-shells in a restaurant (250-300gr) it takes the destruction of about one square metre of rocks by hammer. On the other hand it takes more than 20 years for the habitat to recover.

No Perception and Understanding- Thus No Money for Monitoring

Macic stresses that unlike Italy or Croatia, Montenegro has neither reliable data nor continuous systematic monitoring of physical and chemical parametres of the sea, of which temperature is the foremost.

“This country fails to understand that it cannot rely on single-point data scientific research projects by the IMB“. That's not enough and we must have an ongoing monitoring. Single-point data gathering is not the proper monitoring method. Next year we may do an entirely different project and do something else elsewhere- adds Macic. This kind of situation will pose a problem for Montenegro in accession talks with the EU when Chapter 27 comes to the fore.

Montenegro marine ecosystem monitoring programme is a part of the National Environmental Monitoring Programme and has been in progress since 2008. It is pursuant to the environmental and water resources protection laws, the protocol on classification of surface and underground waters and it's somewhat in harmony with MEDPOL criteria of the European Environment Agency (EPA) in Copenhagen. The EPA is in possession of our marine ecosystem data from 2008 to 2011. It also states on its website that reports for 2012, 2014 and 2015 are of smaller volume 'as a result of under funding while the 2013 monitoring didn't even happen due to inability to follow the obligatory tender protocol. The EPA still hasn't released the report for 2017 while the marine ecosystem data for preceding years are rather scarce and collected without consistency and frequency hence the overall picture remains hazy.

The EPA hasn't responded to questions about the aforementioned problems that CIN-CG submitted. The Agency didn't pay heed to monitoring of the noxious seaweed, except for 2016 when several locations were surveyed although it was known beforehand that Caulerpa had no presence there. There's not a single reference on other invasive animal and plant species that have gained foothold.

Professional and recreational fishermen alike can feel the marine change as the fish catch is not as great as before.. In an interview with CIN-CG the fishermen stated that the Bay of Kotor had an unusually high density of jellyfish with sizeable bell diametres. Also the year before the sea 'flourished' by outburst of algae twice. The second outburst happened in October which is an indicator of sea warming. In recent years 16 new fish species have been discovered.

'I come across the new species almost on a daily basis. They are mostly triggerfish and then lizardfish. Lately I've come across some new very small fish that we haven't seen before. They resemble tropical minuscule fishes in aquariums. Furthermore as we launch closer to the shore the bluespotted cornetfish often ends up in our nets'- says Srecko Andricic, a veteran fisherman from Tivat. He also claims that he spotted mako sharks several times which were chasing their prey and had jumped several metres out of the water. Andricic says that new fish are hard to sell although there are people who like well cooked triggerfish.

'We often net a lot of small squid whose shapes are different from those we know. We bumped into a subspecies of sole which had six spots instead of four. Not many alien fish turn up in my nets but they may in due course prove to be harmful to native fish' –estimates Andricic. He shows all unusual specimen to the IMB experts in Kotor. He says that at times he nets large shrimps of up to 300gr in weight in the waters close to the Bay of Kotor. He saw the same kind of shrimps in Thailand. In Solila near Tivat he found the remains of domicile crabs who lost a fight to a blue crab whose presence is ever growing.

'The blue crabs can be so big that a single one can cover the bottom of a large basket while their pincers can easily cut the 6mm net rope' –says this veteran fisherman from Tivat.

First Hand Encounters in Proximity to Shore

Fellow fishermen from Bar who are into tuna and swordfish 'big game fishing' also run into mako sharks in the open sea. By an unwritten rule the fishermen don't talk to the media about it. Their uploaded photographs and video clips on social network speak about encounters some ten miles off the coast. Sometimes they end up in the catch as it happened near Petrovac recently. Most of sharks are rather small, but witnesses have seen some exceeding three metres in length.

The shortfin mako shark (also blue pointer - Isurus oxyrinchus) is on record as the fastest swimming shark capable of speed of up to 70 km/h. It mainly feeds on tunas, bonitos, mackerels and swordfish. It is considered one of the most intelligent and also one of the more aggressive sharks. Around thirty attacks on humans have been recorded by these sharks around the world.

'It's hard to talk with confidence about mako shark growing numbers in the Adriatic. Those captured are rather small and young. They don't grow fast but we should take notice of them and see what brings them over here' – says Dr Mirko Djurovic.

Joksimovic admits that it's hard to control the spread of invasive species but they have learned something about those arrivals and how they fare in the new environment through information exchange with their colleagues around the region. He expects Montenegro to pass a law on invasive species by the end of this year. He stresses that the EU Directive 1143 on invasive species applies to Montenegro according to the Chapter 27 on environment which is a part of the accession talks with the EU.

The new Montenegrin law on invasive species will mostly be copy-paste of the EU Directive 1143. It will regulate import procedure and prescribe what is allowed or restricted in terms of alien species and draft a list of banned species and those that should be closely monitored. The law will have various provisions for action plans against inadvertent introductions and measures how to contain the invasive species, emergencies, tip offs, tracking and surveillance. The fines will range from 250 to 20 thousand euros.

When it comes to the sea itself the law can't do much there as invasive species arrive there either by chance or due to environmental changes. Deliberate introductions of the invasive species are more likely to happen on land and in fresh waters. The law should primarily aim to prevent deliberate introductions of new species and enable strict control of national borders. Bringing of larvae or grown ups of new species should be either prevented or reduced to a minimum as it is regulated by the already adopted Law on Ballast Water. Importantly, port authorities should be keener in enforcing the law.

'It's a fact that new species are here and they live next to us and with us. Therefore we must find the best way how to scientifically monitor, study and explain them to the public'- concludes  Dr Joksimovic.

Salema porgy and mullet under threat

As for the new species, some came from the Indian Ocean and the Red Sea, and they are known as Lessepsian migrants after Ferdinand de Lesseps, the Suez Canal builder. As much as 14 species have been identified in the Adriatic in recent years, from dusky spinefoot (siganus luridus), silver-cheeked toadfish (lagocephalus sceleratus), reticulated leatherjacket, yellowstripe barracuda to yellowmouth barracuda.

Bluespotted cornetfish have settled in the south of the Adriatic and can grow up to 160cm. It's a predatory fish which feeds on economically important autochthonous species like bogue, pickarel, piper gurnard, anchovy and pilchard. As a consequence it is likely to expect adverse effects on local fisheries and the food chain.

Some of these species like the silver-cheeked toadfish, or fugu fish as it is known in Japan, can be very dangerous to humans.It is a fast-reproducing fish and is detrimental to the fishing industry because it cuts the fishing nets and eats the catch. It contains tetrodotoxin which is 1,250 times stronger than cyanide. It is considered one of the greatest delicacies in Japan once the toxin is neutralized. Fortunately this fish is not a part of our menu.

Dusky spinefoot have also been caught in the Bay of Kotor. It feeds on sea grass and lives in rocky seabeds covered by vegetation. It can grow up to 30cm. Its dorsal and anal fin spines contain venom that is not life-threatening to humans. In the eastern part of the Mediterranean it expelled salema porgy which was an autochthonous species.

'One of the most aggressive new species is bluefish (pomatomus saltatrix) which has spread over the entire Adriatic. It is aggressive with strong teeth and it literally decimates the mullet population. People from the Neretva estuary have already encountered such problems since mullet is one of the fishing industry pillars there. The bluefish has a commercial value on the other hand and its meat is very delicious. It also attracts recreational fishermen' states Dr Aleksandar Joksimovic.

Some of the alochthonous species, like the blue crab (callinectes sapidus), are edible and may be commercially exploited. Another species recently discovered is a shrimp (farfantepenaeus aztecus) which came from the Gulf of Mexico. It is very popular on the US east coast and is the hinge of the fishing industry over there.

The yellowstripe barracuda and the yellowmouth barracuda have inhabited the southern part of the Adriatic while the autochthonous European barracuda is very similar to them. Their meat is delicious hence there's a commercial potential for local communities. The Big Game Fishing tourism can also benefit from the above species.

Coming soon- aquarium and turtle asylum  

The IMB in Kotor has embarked on a project supported by Norweigan donors to found the Centre for Marine Biodiversity Protection whereby Montenegro could give its humble contribution to the world. Furthermore, the first public aquarium in Montenegro is expected by next summer, as well as a turtle rehabilitation centre. Similar centres exist in surrounding countries. The project also aims to help the authorities in Montenegro get a better view of all that stands in their way in terms of fulfilling the Chapter 27 goals of the accession talks. Therefore five workshops are on the schedule. They will help to scrutinize the national legislature in regard to the EU harmonization process.

Siniša LUKOVIĆ