Enlarge By Maciej Czoska, AP Adam Buczynski carries a dog found floating on an ice floe Tuesday, 15 miles off the Polish Baltic Sea coast in Gdynia. Buczynski, a sailor from the ship Baltica, pulled the dog from the ice floe. WARSAW (AP)  A frightened, shivering dog was rescued after floating 75 miles on an ice floe down Poland's Vistula River and into the Baltic Sea , officials said Thursday. Now his saviors just have to figure out who really owns him. Four people have already claimed him, but so far rescuers say there's been no wagging tail of joy from the miracle dog they nicknamed "Baltic." PAW PRINT POST: Dogs and cats reign in this community The dog's frozen odyssey came as Poland suffers through a winter cold snap.Temperatures have dipped to below minus 4 degrees Fahrenheit. The thick-furred male dog was found adrift Monday 15 miles out in the Baltic Sea by the crew of the Baltica, a Polish ship of ocean scientists carrying out research. Researcher Natalia Drgas said Thursday that the rescue was difficult and at one point it seemed the dog had drowned. "It was really a tough struggle. It kept slipping into the water and crawling back on top of the ice. At one point it vanished underwater, under the ship and we thought it was the end, but it emerged again and crawled on an ice sheet," Drgas said. At that point, the crew lowered a pontoon down to the water and a crewmember managed to grab the dog by the scruff of his neck and pull him to safety. Too weak to shake off the frigid water, Baltic was dried and wrapped in blankets. After he warmed up, he was massaged, fed and soon got on his feet to seek company, Drgas said. A firefighter in Grudziadz, on the Vistula river 60 miles inland from the Bay of Gdansk, told the Associated Press the dog was spotted Saturday floating on ice through the city. Firefighters tried to save him but could not approach the dog due to shifting ice sheets, said the officer, who spoke on condition of anonymity. The Baltica crew, now moored in the port city of Gdynia, has been searching for the dog's owners, ship captain Jerzy Wosachlo said. So far four people have claimed him, but Baltic has not claimed any of them back, Drgas said. The dog didn't welcome the first two people to come for him, keeping his distance and showing no recognition toward a couple on Wednesday and a woman on Thursday who both said he was theirs. Two other would-be owners were still en route to Gdynia for a possible reunion. Once in port, the brown-and-black mongrel was taken to a veterinarian, who found him in surprisingly good condition and estimated his age at around 5 or 6 years old. Veterinarian Aleksandra Lawniczak said the 44-pound dog was clearly frightened but in strikingly good shape and had suffered no frostbite. A dog with thick fur and a layer of fat can survive such cold conditions for as long as eight days if it has water to drink, Lawniczak said. She described Baltic as a friendly dog who was clearly well treated before getting lost. Wosachlo said the research team is prepared to adopt Baltic if his original owner is never found. Copyright 2010 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed. Guidelines: You share in the USA TODAY community, so please keep your comments smart and civil. Don't attack other readers personally, and keep your language decent. Use the "Report Abuse" button to make a difference. You share in the USA TODAY community, so please keep your comments smart and civil. Don't attack other readers personally, and keep your language decent. Use the "Report Abuse" button to make a difference. Read more