‘Hooked and Hungry’: Carnivorous ‘death-ball’ sponge found in Southern Ocean depths

A team of researchers exploring one of the planet’s most remote waters has discovered 30 previously unknown species deep beneath the Southern Ocean. Among them is a carnivorous “death-ball” sponge that has fascinated scientists with its unusual and deadly design.

What makes the 'death-ball' sponge so unique?
Scientists from The Nippon Foundation-Nekton Ocean Census made the discovery during two 2025 expeditions with the Schmidt Ocean Institute. In a press release, they described the “death-ball” sponge as a spherical organism covered with tiny hooks used to trap prey. This predatory trait makes it stand out from most sponges, which typically filter-feed on microscopic particles drifting through the water.

Researchers say the sponge’s shape and hunting method reveal how extreme environments foster extraordinary adaptations. The team also observed ‘zombie worms’ (Osedax sp.), which feed on whale bones using bacteria instead of mouths or stomachs. Although not new to science, these worms were a reminder of the unusual survival strategies thriving in the dark ocean.

Dr Michelle Taylor, Head of Science at The Nippon Foundation-Nekton Ocean Census, said the Southern Ocean remains largely unexplored. She noted that less than 30 per cent of the expedition’s samples have been analysed, yet 30 new species have already been confirmed. “By coupling expeditions with species discovery workshops, we compress what often takes more than a decade into a faster pathway while maintaining scientific rigour,” she said.