The huge growth or malformation on its right side of a humpback whale is being investigated.

The huge growth or malformation on its right side of a humpback whale is being investigated. Blue Dolphin Marine Tours

THE marine life of Hervey Bay waters continues to keep researchers and local tour operators fascinated.

Having spotted a humpback whale on Sunday with a strange growth on its right side, Blue Dolphin Marine Tours owner Peter Lynch decided it was worth investigating.

After forwarding photos to Marine Mammal Research, the whale's plight is being investigated closely by research networks.

A Department of Environment and Heritage Protection spokesperson said its experts were not able to determine from a single still photograph what might cause the apparent lump.

Marine Mammal Research project co-ordinator Scott Sheehan said from the photo the humpback whale appeared to have its pectoral flipper missing.

"The lump may be a genetic abnormality, but the swelling when seen along the dorsal surface looks like it is under tension, like a big abscess or something," he said.

"The mass/swelling may be rolling the pec ventrally and giving the appearance of no pectoral flipper."

Asked what should be done about the whale, Mr Sheehan said the answer was "nothing".

"This whale was actively swimming, although it does appear slim from the photos," he said.