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Support Research and Help Track Caribbean Seaweed

By Joan Conover - SSCA — last modified Nov 16, 2018 02:31 PM
Contributors: The opinions expressed in this article are the author's own and do not reflect the view of or the World Cruising Club.
All you have to do if you spot Sargassum (Caribbean seaweed) is log the incident (date/time/photo) and post the data to the research website on arrival somewhere in the tropics with internet.

Published: 2018-11-16 00:00:00
Topics: Atlantic Crossing , Caribbean Sea , Environment

Support Research and Help Track Caribbean Seaweed

Sargassum line offshore - photo by GCRL

The Caribbean Seaweed Problem (Pelagic Sargassum)

Starting primarily in 2011, massive quantities of pelagic (floating) Sargassum occurred throughout the Caribbean, impacting aquatic resources, fisheries, shorelines, waterways, and tourism. The 2017/2018 season has been significantly worse - over 50% worse than previous infestations.  A report from the southern Caribbean mentions;  “The smell at the moment is near intolerable; the build up has increased massively in the last week or so and now there is too much aggregated for the tide to remove it. Furthermore, there is so much ashore already that new influx can only sit on and in the water. The wet Sargassum rots on the shore, and sea life dies on the mass floating at the shoreline.“

What can cruisers do to assist?

Under development is an early warning system for the arrival of Sargassum, but more information on the spread, timing of plant migrations and validation of type and stages are critical.

Over the past several years, several research facilities have been developing technologies to identify the location of weed masses based on satellite imagery ( While this seems simple, it has required on the ground, or in this case sea, knowledge of where volumes of weed had infested. This then allowed comparison to satellite data to develop suitable applications.

Cruisers can get the word out to other concerned people and continue to report the weed, especially important as now there is such a large amount of growth of the weed.

Reporting your findings

For several years, private citizen scientists and cruisers have reported their Sargassum findings to the Gulf Coast Research Laboratory’s (GCRL) Sargassum research group headed by Jim Franks (University of Southern Mississippi). GCRL’s Senior Scientist, Jim Franks, asks for cruisers to input their data (Lat/long/DTG), photographs if possible, and comments to a website designed for reporting Pelagic Sargassum observations.

This years reported data included close up photographs of the weed on deck with a dark background (a black garbage bag works fine) to allow identification of the stage of development of this mobile plant.

Data provided to this site will continue to be used by GCRL scientists and colleagues throughout the region to identify the source and examine the movements and causes of these extraordinary events.

Please file your report on the form at

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