Necropsy finds German Baltic Sea humpback whale likely died of severe bacterial infection

A dead male humpback whale discovered floating on its back in the Greifswalder Bodden between the island of Ruegen and the German mainland died of a suspected bacterial infection and sepsis, according to preliminary necropsy findings from the German Oceanographic Museum (Deutsches Meeresmuseum). The animal, measuring approximately ten metres in length and weighing seven tonnes, was estimated to be between three and four years old. Officials from the Baltic Sea Waterways and Shipping Authority recovered the carcass on 13 August 2026 and transported it by sea to the island of Daenholm for examination. Pathologists estimated the time of death as 12 or 13 August 2026, finding no external injuries from ship propellers or fishing gear.

Abscesses along the spine

The examination, concluded on 15 August 2026, revealed four pus-filled abscesses. The largest abscess measured 110 centimetres in length and 42 centimetres in width, spanning roughly one-tenth of the animal's total body length along the spine. Another abscess extended directly from the bone outward through two round openings in the rear back, leaving nearby vertebral processes partially porous. Pathologists also located an abscess at the ball joint of the right pectoral fin.

The whale must have suffered enormous pain, especially while moving, because most of the abscesses were located directly on the spine.

Evidence of starvation and skin disease

Internal examinations showed that the whale had endured a prolonged period of starvation before dying. Its blubber layer was six centimetres thick, and both the stomach and small intestine were completely empty, with only a small quantity of brownish residue found in the rear part of the large intestine. The whale displayed two enlarged lymph nodes in the digestive tract, while its skin was discoloured reddish-brown from the snout to the dorsal fin, with large sections of the top skin layer missing. Scientists attributed this skin condition to a weakened immune system. Aside from a minor parasite presence in the blubber near the left shoulder blade, the body was largely parasite-free.

Which bacteria were specifically involved and whether the suspicion of sepsis is confirmed will be shown by bacteriological and virological examinations in the laboratory.

Necropsy conditions and earlier sightings

A team of 13 scientists conducted the post-mortem examination on 14 and 15 August 2026 in direct sunlight, with outdoor temperatures reaching 30 degrees Celsius. Rapid decomposition and gas buildup, including inside the animal's swollen tongue, prevented researchers from gathering viable tissue samples from the brain, lungs, and kidneys. Museum specialists noted that the distinctive skin lesions and the restrictive placement of abscesses on the spine and pectoral fin match earlier sightings of a young humpback whale observed off the coast of Schleswig-Holstein, inside Wismar harbour, and along the Polish coastline.