Look over the side of a ferry in Eminönü or Kadıköy in İstanbul, and chances are you will see one, two or 10 of what some scientists are labeling a new water pollutant. Not the odd grocery bag or half-eaten simit, but one of the many jellyfish proliferating in the Turkish seas. Composed of 95 percent water and lacking both brains and blood, the translucent creatures, resembling pale, floating disks with tentacles streaming off of them, are nonetheless formidable marine predators.

Rising jellyfish numbers worldwide have been drawing the attention of scientists and some in the media over the past decade, but the first half of 2008 has seen a particular increase in coverage due to worries over tourism in the Mediterranean, and on Spanish beaches in particular. Sometimes floating in menacing "blooms," or schools, jellyfish -- sometimes just an eyesore, and sometimes a menace -- have raised concerns about possible beach closures and impacts on the European and Mediterranean tourism industries similar to problems faced by nations including Japan, Ireland, Australia and Peru.

A sustained increased of jellyfish in the world's oceans and seas could have a disastrous effect on tourism, fishing and the global economy. The beginnings of a similar phenomenon can be observed in İstanbul and other coastal regions in Turkey, where media have picked up the story on the increasing numbers jellyfish but drawn only uncertain conclusions. Will jellyfish be responsible for wrecking Turkey's fishing industry and reverse the popularity of Turkish beaches for foreign and domestic travelers? Experts speaking to Sunday's Zaman say there is definitely an ecological problem, but that the extent of it -- and the means to solve it -- can only be evaluated after much more research into jellyfish and their place in and effect on Turkey's ecosystem.

Miner's canary of the high seas

International media reports have focused on jellyfish as indicators of environmental problems with potentially serious ramifications that go far beyond disrupting beach tourism. Jellyfish, whose populations usually swell in the summer as waters warm and recede again in winter as the world's seas and oceans cool off, are displaying an alarming trend of reproducing over increasingly longer periods that are growing more and more irrespective of season. Many point fingers at global warming right off the bat. While this may seem a convincing argument -- the Earth's temperatures are going up and, along with them, the temperatures of oceans and seas, creating ideal breeding grounds for jellyfish -- ecosystems aquatic and terrestrial are incredibly complex, making it hard to pin the blame for an irregularity on any single cause. The experts that spoke with Sunday's Zaman emphasized that jellyfish were only one part of a larger environmental puzzle.

Banu Dökmecibaşı, the head of Greenpeace Mediterranean's "Defending Our Mediterranean" campaign, is hesitant to pass judgment on the issue, citing a need for more research into the cause of the jellyfish population boom in the Mediterranean. She said a number of questions remained about the issue in Turkey and that jellyfish populations in Turkish waters had not been as extensively studied as those in Spain and other places where the problem had become more visible.

"It's all connected, and therefore difficult to determine exactly what's affecting what. There's climate change involved, jellyfish types native to the Mediterranean and jellyfish that come from other areas. If they're coming from other areas, why is this happening? This is an ecosystem with many factors involved -- these things need to be researched. Jellyfish reproduce in cycles. If this is mostly a normal phenomenon, there's no need to intervene. But if it's abnormal, caused by man, then it needs to be taken very seriously and addressed. If it's related to global climate change, then the root action will be to address the problem of burning fossil fuels and switching to renewable energy forms with less environmental impact," Dökmecibaşı said.

"We know that the temperature of the Mediterranean Sea's waters has risen. But beyond that, it's not clear what the root causes are behind the jellyfish population growth. At this point it could still be a seasonal, cyclic phenomenon, with some connections to over-fishing," she added.

Global warming has heated the Earth's seas, resulting in warmer, saltier waters that are ideal for jellyfish reproduction. In addition to more favorable reproductive conditions resulting in more jellyfish, jellyfish compete with fish in more ways than one: They eat what fish eat as well as eating fish.

Turkish Marine Environment Protection Association (TURMEPA) Secretary-General Levent Ballar, speaking with Sunday's Zaman last week, also noted that beyond being one of the many signals of global warming-driven climate change, the increasing jellyfish numbers were part of an ecosystem problem tied into fishing and waste management.

"This jellyfish explosion stems from a decrease in the population of species such as tuna, swordfish and sea turtles, all of which feed on jellyfish. Another crucial factor is that the fish population has shrunk due to uncontrolled fishing," Ballar said, adding: "Industrial and domestic waste, as well as organic substances carried by rivers, pose another threat to the seas. The increasing jellyfish population curbs fish populations as the former feed on fishes' food as well as larval fish."

Jellyfish not affecting Turkish tourism -- yet

As Ballar put it, Turkey's unique geography -- "surrounded on three sides by four different types of sea" -- makes it particularly vulnerable to jellyfish population growth in other areas of the world. There have so far been no reports of large numbers of tourists dissuaded by jellyfish problems along Turkey's coasts, but the potential looms as non-native species of jellyfish are swept into Turkish waters.

"As far as tourism goes, tourists in Turkey aren't used to seeing jellyfish in the water, especially not in large numbers, and so it's an aesthetic problem for now," Greenpeace's Dökmecibaşı said. But she agreed that if the problem continues tourists will be some of the first to notice. "Jellyfish are generally seen around coastlines, where tourists often flock in ferries and to beaches."

Ballar points to the danger of the introduction of new types of jellyfish to Turkish waters: "Alien species, including jellyfish, are believed to be carried through the Suez Canal into the Mediterranean. They harm the ecological balance and damage the ecosystem at sea. Some are very dangerous, with stings poisonous enough to kill humans."

The two main types of jellyfish in the Turkish Mediterranean today are Aurelia aurita, known commonly as the "moon jellyfish," and Rhizostoma pulmo. They are both native to Turkish waters and harmless. The proliferation of these will impact fishing and aquatic systems, but for tourists they will be more of an "eyesore" than a threat.

The Rhopilema nomadica, on the other hand, is a jellyfish that can sting severely and could pose quite a problem for tourists if the species, first spotted in large numbers Turkish waters in 1995, reproduces unchecked. Ballar warns: "Especially in the last few years, our seas have seen an increase in foreign jellyfish species. …Their migration is facilitated by the Suez Canal from the Red Sea into the Mediterranean. For example, Rhopilema nomadica jellyfish are native to the Red Sea, but they have migrated to the Mediterranean, negatively affecting fishing, tourism and human health."

More research, government support needed

Phoned by Sunday's Zaman, Turkey's Nature Association (Doğa Derneği) said it was also concerned with jellyfish population growth but that it did not yet have much information on the phenomenon. Professors from İstanbul University and the Middle East Technical University Institute of Marine Sciences expressed regret that they had no detailed research on jellyfish specific to Turkish waters. This sentiment was echoed by environmental and marine organizations across Turkey: A problem does exist, but more research, time and money are needed to assess the specifics of Turkey's jellyfish population.

"The government needs to support universities and researchers in learning more about the jellyfish increase and how this will affect the waters of the Mediterranean," Dökmecibaşı said. Ballar agrees, adding, "No matter what the cause, this situation should be a strong example to people that our marine ecosystems are important and that everything we do has an impact."

TODAYSZAMAN