So, it must come to an end. Saturday the Baltic Sea Expedition finished. We arrived to Stralsund in Germany, where Hanse Explorer was going to be transformed back to its normal look. This job toke days, as everything had to be packed properly and send back to Spain, where lots of the stuff, including the ROV, is going to be used on Oceana’s next expedition in the Mediterranean Sea. But before arriving to Stralsund, we managed to do several underwater recording in the southern Baltic Sea. We did scuba diving and ROV dives in different offshore areas in Swedish, Danish and German waters.
We arrived in the Gulf of Riga Tuesday afternoon. The Estonian’s Muhu archipelago separates the Gulf of Riga from the rest of the Baltic Sea, and several large rivers provide fresh water to the gulf. The gulf is quite shallow with 67 m as maximum depth. The salinity is lower here than in the Baltic Proper. Because of these conditions the Gulf of Riga is in risk of eutrophication and algae bloom in the spring and summer times. The first dive we had here was in a MPA close to a small island, called Ruhne Island. Here the divers had a dive with bad visibility, due to algae.
As we were sailing from the Bothnian Sea towards the Åland Islands, the wind increased. Our plan was to go diving near a small island in the region Jomala west of the main town Mariehamn, but when we arrived the weather has turned so bad that diving in this non-sheltered area was impossible. Instead we sailed into the harbor of Mariehamn, which is located at the main island Fasta Åland, and after arriving we decided to take the zodiacs a couple of miles south east and go diving in sheltered area there.
Fortunately the weather has improved, so it again is possible to work and walk (!) onboard. As we were moving north the nights were getting longer and longer, which impressed even a Scandinavian as me; at 1:30 AM there was still twilight in the Bothnian Bay. As expectedly the temperature drops when going north, which indeed could be felt when being outside. We spotted the last small pieces of ice on the sea; these are probably melted in a few days from now.
The last days have been unusual for this expedition; we had spent more time in land than at the sea. We arrived to Helsinki on the 19th May, where the Oceana Baltic Sea Expedition team had time to explore the city. By being onboard on this expedition we are working every day, also in weekends, and therefore a day off in harbor is well deserved. On the 20th May we left Helsinki for sailing to the most eastern part of the Baltic Sea, St. Petersburg in Russia. St. Petersburg is placed where the river Neva runs into the Baltic Sea, and therefore St.
After spending less than a day in Tallinn, it was time for us to continue our expedition for doing recordings in Estonian and Finnish waters. We spend the next days to explore some areas close to the Estonian island Hiiumaa, both inside and outside marine protected areas. The divers were lucky to see and document a lumpfish (Cyclopterus lumpus). The lumpfish has a quite characteristic appearance, as it looks tropical and has a special suction disk; the fish can use these discs to adhere to the substrate.
Today we are spending the day sailing towards Tallinn, where we will make a stopover from this evening until tomorrow. Though having at tight time schedule, we made a stop close to an island called Osmussaar in Estonia to do underwater filming, taking a sample from the seafloor and measure the oxygen in the water column. There was no visible life at 110 meters depth, no either in the sediment sample, which again tell us about the critical situation the Baltic Sea is in.
After filming the German waters, we now sailed into the Polish water where we did recordings offshore, inclusive at a sandbank and two places in the Gdansk Deep. At the shallow sandbank, called Oderbank, the divers went diving directly from Hanse Explorer. We could see their bobbles from the boat, while they dived around it.
The reason for why we did a stopover in Copenhagen was, beside the press conference, to exchange some members of the Oceana team. We had to say goodbye to Carlos Minguell, Gorka Leclercq and Jose Manuel Saez ‘Pisha’, which were going back home. Instead we could welcome our new team members which include Carlos Suarez (photographer and diver), Enrique ‘Kike’ Talledo (videographer and diver), Josep Maria Fortuny ‘Pitu’ and Daniel Sanchez (ROV technicians) and Sole Esnaola (deck support). Great to have new people onboard!