Just after sunrise, ours is the only small cruise ship anchored in the bay of Vis. Most of the passengers are still asleep, but for Captain Ante Letica, it’s just another day’s work. At 06:00, as the Jadrolinija ferry, the government-owned transport backbone of the islands and coastal towns, leaves the port, we follow behind us and set sail.

Croatia boasts a 6,000 km long strip of mountainous coastline and over 700 largely unspoiled islands. The Adriatic is famous for its clean and clear azure waters, a paradise for snorkeling and diving.

I’m on a small boat cruise from Dubrovnik to Split aboard the 148ft My path, which Letica purchased in 2018 with a loan from its bank. I swim every day from the back of the boat. We sail in and out of tiny Venetian-style ports, moor next to Ottoman castles and wander the cobbled streets of Korkula, Starigrad and Hvar, which have changed little over the centuries.

Yet when the engines roar or I hear the strange smell of diesel fumes, I wonder just how much damage small boat cruises do to the environment. In 2019 there were over 350,000 boats on the water in Croatia.

“The future is scary,” says Letica. “The problem is traffic. More and more people are going to sea, and sailing is becoming more and more popular as the equipment improves. So there will be more ships, but the Adriatic is a small sea with small ports. And with more and more flotillas, pressure on ports is a growing problem.”

Every five weeks, Letica stops in Split to refuel, taking 40,000 liters of fuel on board. Our week-long cruise from Dubrovnik to Split uses around 4,000 litres. The cleaner diesel it uses complies with the recent and stricter IMO 2020 regulations, which reduce the polluting sulfur content of fuel oil used on board ships. He says diesel is currently the most convenient fuel; biofuels are not suitable for marine engines.

Small cruise ships emit a small proportion of total shipping emissions. Jerzy Herdzik of the Maritime University of Gdynia in Poland estimated that maritime transport generated between 2.5 and 3.0% of the carbon dioxide pollution in the world. Transport generates about a quarter of global emissions.

Could Letica have bought an electric boat? No, he replies. It’s not just that the batteries aren’t big enough for the route yet; it’s about passenger expectations.

“Thirty years ago, our passengers did not expect Wi-Fi”, explains Letica. “They didn’t expect to have a TV in their bedroom. We didn’t have all those dishwashers or cell phones or laptops to charge.”

My path is Letica’s ship – he will own it entirely once he pays off the bank loan he took out to buy it. His wife and grandson are on board for the first two days. Warm and charismatic, he treats the crew almost like family, but they never cross the line. Discipline is tight. In case of disagreement between the crew members, they leave the boat. The ship is immaculate, the food excellent, but there is no waste.

Tourism generates around 20% of Croatia’s GDP and operators must prove that their activities create local wealth. However, as a semi-enclosed sea, the Adriatic is becoming increasingly vulnerable to the impacts of economic activities such as tourism.

One of the key environmental considerations for Letica is how to dispose of “black water”, wastewater from bathrooms and toilets. My path black water is on board in a black box, discharged at the port at the end of each voyage. He welcomes the stricter regulations that have accompanied Croatia’s accession to the EU.

Croatia complies with Annex IV of MARPOL of the International Maritime Organization, prohibiting the discharge of black water into the sea within 12 nautical miles of land, unless it has been or treated by a sewage pump.

The idea of ​​change does not phase Letica – after all, he lived through communism, the last war and the transition beyond. “Since the 1990s we have had choices. It is possible to choose better equipment and fuels. Change takes time – it will take time to change the engines of ships. But we have to keep up with what is modern and the best practices if we want to work in the tourism industry.”

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