Rescue teams in northern Germany are in a desperate race against time to save a humpback whale stranded in shallow waters of the Baltic Sea.

Experts convened on Timmendorfer Strand beach on Tuesday morning, attempting to refloat the 10-metre-long (30-feet-long) mammal.

Previous attempts on Monday afternoon, involving police boats, inflatable vessels, and firefighter drones guiding operations, proved unsuccessful, with the high tide around midnight also failing to free the animal, according to German news agency dpa.

Despite the ordeal, the whale remains alive, breathing, emitting sounds, and occasionally lifting its head, Carsten Mannheimer of the marine conservation organisation Sea Shepherd told dpa.

Rescue efforts have been fraught with difficulty. Rescuers initially managed to turn the whale, orienting its head towards deeper water in the hope it would swim free, but the animal subsequently reverted to its original position.

Boats from the coast guard and the fire department passed by, creating large waves in the hope of freeing the animal — but also without success, German public broadcaster NDR reported.

The animal, which weighs several tons, cannot actively be pulled back into deeper water because it could be seriously injured in the process, experts said.

“If the whale can’t get off the beach, it’s a death sentence for the animal,” Sven Biertümpfel of Sea Shepherd told NDR, adding that the whale’s condition is deteriorating by the hour.

Experts assume that the whale is a young male, as males, unlike females, tend to migrate. It also seems to be the same whale that has been spotted several times in the port of Wismar in eastern Germany in recent weeks.

It was not immediately clear why the whale got stranded, but rescuers found parts of a fishing net wrapped around the body of the whale, which they managed to cut off.

In the meantime, police cordoned off the beach area with construction fences to keep a large crowd of onlookers at bay.

“It is very important that the animal does not become even more stressed,” police spokesperson Ulli Fritz Gerlach said.