Dolphin poo plays 'significant role’ in helping coral reefs survive, says new study

Dolphin poo could be the key to saving the world’s coral reefs, according to a new study.

Spinner dolphins, famous for their acrobatic marina displays, have some very special excrement. Their poo has “reef-enhancing nutrients” which are not to be underestimated, a report by Zoological Society London (ZSL) finds.

The dolphins are giving threatened coral reefs in the Maldives and Chagos Archipelago a helping hand by pooing in the shallow lagoons. Published this week, the study shows that the amount of nitrogen absorbed by spinner dolphins during their daily commute can improve coral reef productivity and resilience.

The species plays a “significant role” in supporting the vulnerable ecosystems in this region and scientists are calling for their protection.

Spinner dolphins are about 6.5 feet (around 2 metres) with a long, thin snout. They have white stomachs and dark grey backs and live in warm ocean waters around the world, including near Thailand, along the Pacific coast of Central America and around the Hawaiian islands.

The species is not classified as endangered on the IUCN red list, but it does face threats from potential entanglements with ghost nets and other marine debris, collisions with ships, noise disturbance, habitat degradation and human activity.

A team in the Maldives used a combination of visual observations and underwater recordings, some hailing from tourist whale watching trips, to monitor the spinner dolphins. Around 105 spinners live in this area.

They noticed that the dolphins enter atoll lagoons (ring-shaped coral reefs) in the morning, where they then spend half the day resting, before leaving in the afternoon to hunt and forage in the deeper waters at night.

During the first half of the day,