Climate change: Seychelles' sea cucumber stock falls by 30%

One piece of good news is for the prickly redfish, which has increased from 3 million to more than 4.5 million in 2021. (Paul Asman and Jill Lenoble, Flickr) Photo License: CC BY 2.0

The stock of sea cucumbers in Seychelles is depleting by 30 percent due to various factors, including climate change, according to the results of a recently conducted survey.

The aim of the survey organised by the Seychelles Fishing Authority was to assess the abundance of all sea cucumber resources, not just those that are commercially exploited.

In the survey, headed by Australian consultant Tim Skewes and a group of local sea cucumber divers, 206 sites from the Mahe Plateau and the Amirantes Banks were visited but data was collected on 192 sites only because of bad visibility and strong currents on 14 sites.

The findings of the survey were presented to people working in the sea cucumber industry last week.

The results show that one species, the black teat fish, is under threat. Since 2004 the population was more than 7.5 million but has fallen to 1.4 million in 2021.

A decline has already been recorded for two other species - the white teat fish has declined from 4.5 million in 2004 to less than 500,000 in 2021 and the average stock of the pentard species decreased from around 4.5 million in 2004 to over 2.5 million in 2021. 

One piece of good news is for the prickly redfish, which has increased from 3 million to more than 4.5 million in 2021.

Australian consultant Tim Skewes said that the 30 percent depletion of the species is due to various factors.

"Climate change is affecting the ecosystem and fisheries and there is a need to do more research on this. Other potential impacts are fishing and the fact that some species do vary on an annual scale," said Skewes.

Seychelles' minister for fisheries, Jean-Francois Ferrari, said that research will give all partners concerned guidance on the future management strategy of sea cucumber as resources."

He stressed the importance of preserving the stock and said that "you all have a responsibility to ensure that we preserve this resource. We have to think ahead because our responsibility is towards our children who will join the industry in the future."

James Lesperance, a processor in the sea cucumber industry since 1999, agrees that Seychelles needs to implement some measures to ensure a healthy stock for the future.

The new survey was the result of a recommendation from the 2017 fisheries stock assessment that the Marine Resource Assessment Group (MRAG Ltd) based in the United Kingdom. The group highlighted that there was a need to increase confidence in stock status and encourage SFA to do a fisheries stock assessment.

Senior fishery scientist from SFA, Stephanie Hollanda, said that the last fisheries independent survey was done in 2004 and 2005 and there is a need for a new assessment.

The Management Advisory Committee board composed of officers from SFA and the sea cucumber industry will meet to decide on the new measures for the new fishing season expected to open in October.