Reconstructing a Sperm Whale’s Tale

Four years after a female sperm whale was found dead in Singapore waters, scientists are starting to put the pieces together to reconstruct the story of how she got to be there.

Discovered off Jurong Island in July 2015, she was the first (and only) sperm whale sighting that has been recorded here till date.

The dead female sperm whale, found in the waters off Jurong Island, July 2015.

However, her life was shrouded in mystery – no one knew where she came from, or what happened prior to her death.

After years of research, Marcus (our former curator of mammals, currently on study leave) and his co-authors have recently published a paper that aims to shed light on the sperm whale’s life.

Their study, published in PeerJ, found that the sperm whale could have originated from a population in the Indian Ocean, close to the Cocos (Keeling) Islands or Indonesia.

Before she died, the whale was probably hunting in waters outside Singapore or the surrounding enclosed seas, as suggested by the large diversity of deep sea prey items found in her gut.

Sorted prey items (squid beaks) found in the sperm whale’s gut.

Interestingly, pyrosomes (cylindrical-shaped colonies comprising hundreds/thousands of individual organisms known as zooids) were one of the prey items discovered. According to Marcus, this is unusual as they seem to be seldom eaten by female sperm whales.

Other than prey items, ingested plastic trash were also found in the sperm whale’s stomach. Beyond providing additional evidence on where she could have originated, it also highlights the prevalence of plastic marine trash in the ocean and the potential danger they pose to wildlife.

Cups and other ingested plastic trash retrieved from the gut.

“This study provides an increase in the understanding the diet and natural history of the sperm whale in Southeast Asia. The combined analyses of stomach contents, DNA, and hydrodynamic modeling could provide a context to future studies on the sperm whale strandings, and have broader applicability for other marine mammals in the region,” said Marcus.

Read the full paper here.

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The salvage, exhibition, research, and education programmes on the Singapore sperm whale were made possible by the generous public support of the Jubilee Whale Fund.