Caribbean fishers are bracing for another year of sargassum influx, which has had a devastating impact on fisheries and tourism in recent years.
Barbados, St. Lucia, Trinidad and Tobago, and Mexico have all reported a recurrence of unusually high levels of sargassum thus far in 2018. A February report on the Caribbean News Service states simply, “The dreaded Sargassum seaweed is back.” Trinidad's Newsday newspaper reported, “Sargassum seaweed has once again invaded several beaches along Trinidad’s East coast as mounds of the brown seaweed have once again washed ashore along the Mayaro coastline.” And a Mexican online publication's headline announced dramatically, “Sargassum attack! Costa Maya Mahahual under siege again in 2018.”
A study published last year on the sargassum's impact on Barbados' important flying fish fishery noted the first large-scale sargassum influx occurred in 2011, but the quantity of seaweed has increased drastically in the last two events in 2014 in 2015. The influx has also occurred on other Caribbean islands, including Trinidad and Tobago, Antigua and Barbuda, Grenada, and St Lucia.
A 2017 technical report by the Centre for Resource Management and Environmental Studies, entitled “Socio-economic impacts of Sargassum influx events on the fishery sector of Barbados,” cited several adverse effects of the sargassum on the region’s fisheries.
These included “increased number of juveniles following the seaweed, [which] also meant more juvenile fish were caught, sold and eaten, and less were available for replenishment of the stock ... This was particularly so for dolphinfish, where the sargassum mats were bringing a large number of juveniles into Barbadian waters, which fishers reported seeing and catching in and around the mats.”
There was also a major decrease in flying fish catch in 2015 due to the sargassum event, with the island's Fishery Division reporting “277.9 tonnes landed from January-June in 2015 compared with 981.3 tonnes landed over the same months in 2014.”
The report also noted that “the large mats and patchy windrows,” of the sargassum offshore made it difficult for fishers to operate their boats and fishing gear, especially the flying fish gillnets. Fishers reported that the sargassum mats not only covered a large surface area, but were also several meters deep. As a result, flying fish fishers were unable to successfully set and retrieve their gillnets, and the sheer weight of the entangled sargassum also damaged the nets.
Problems with setting and retrieval of sub-surface gear were also reported by some longliners, and surface hook-and-line fishing was also affected as the line gathered sargassum, which then became entangled on the hook, rendering it ineffective for catching fish, the report noted.
Efforts are ongoing to find viable solutions for dealing with the sargassum events, which are predicted to become the new normal as seas and oceans become warmer due to climate change, the report concluded.
