From the University of Southampton, SARTRAC investigator Prof Robert (Bob) Marsh and PhD student Yanna Fidai visited the Centre for Resource Management and Environmental Studies (CERMES) at the Cave Hill campus of the University of the West Indies, over 24-31 March 2022. The Cave Hill campus is located in the northern suburbs of Bridgetown in Barbados, which lies a little east of the Windward Islands of the Lesser Antilles, at the entrance to the Caribbean Sea. Located at approximately 13°N, 59°W, Barbados enjoys a tropical climate, with steady trade winds blowing from the east-northeast and ocean currents typically from the east-southeast – both consequential for the drift and beaching of Sargassum seaweed, a focus of SARTRAC. After two years of intermittent lockdowns and restrictions on international travel, we finally had the opportunity to meet our Project Partners, until now familiar only through so many online discussions. We had the further opportunity to join in some fieldwork, on beaches and offshore, trialling new ways to monitor beached Sargassum, and collecting ground truth data to train our satellite algorithms. Here is a day-by-day record of our activities and experiences.
Preparation: To get ready for fieldwork and to familiarise with the equipment, Prof Jadu Dash and Yanna spent some time developing the protocol and exploring how to use the field spectrometer in a mock-beach environment outside Building 44 on our Southampton campus. Additionally, NERC FSF (who kindly loaned the field spec for this project) offered some virtual training on how to use the kit properly.
Thursday 24th: On arrival at Bridgetown airport, we were met by Southampton colleague, Prof Jack Corbett, coming to the end of his week-long visit. Jack has been working with Dr Janice Cumberbatch on the governance issues related to Sargassum. With Jack, we met up with Janice, Prof Hazel Oxenford and Catrina Hinds, for dinner together.
Friday 25 March 2022: First thing in the morning, Bob crossed the road next to our hotel in the Hastings suburb of Bridgetown, and 2 minutes later reached a near-deserted beach, making first contact with Sargassum, washed ashore in limited quantities on this semi-exposed southwest coast; after breakfast with Jack, we finally arrived at CERMES, perched on the edge of the Cave Hill campus, to start work! Yanna met the graduate student and technical team at CERMES (Dale Benskin, Joe Weekes, Mia Clarke and Micaela Small) and got stuck in straight away experimenting with adding a multispectral camera to the CERMES drone and taking it out to a testing site, unfortunately it didn’t go so well and the drone struggled with the weight of the camera, so it was agreed that we would only use the RGB (Red Green Blue) camera at the beach fieldwork site as it’s a high wind environment and the risk of using the additional payload was too high. In the afternoon, in the CERMES lecture room, Bob presented Southampton SARTRAC work and plans to the students and technical staff who are working on Sargassum. Late that evening, over a beach walk and rum punch, we discussed the topic of ocean harvesting of sargassum (for biodiesel) with visiting academic entrepreneur Ute Marx from Germany, visiting UWI for a conference.
Saturday 26 March: We took a clockwise round-island tour, courtesy of Hazel, to eventually reach major inundations of Sargassum on the windward east coast. Passing through a magnificent mahogany forest, we reached Cherry Tree Hill and views across the geologically distinct Scotland District of the northeast part of the island. This was our first sight of the wild east coast, looking down on Walker’s beach, where CERMES have painstakingly undertaken Sargassum surveys every fortnight for nearly a year! Travelling further north on the east coast, via the rural communities of Boscobel and Pie Corner, we eventually stood on fossil corals to gain a clifftop vantage point overlooking Gay’s Cove, turned brown with Sargassum; via the beautiful coastline of Bathsheba, we reached Conset Bay in the southeast, a small fishing port where fishers daily navigate the treacherous reef to reach favoured fishing spots, and where Sargassum has also piled high – right up to the landing stage.
Sunday 27 March: Up early, Bob went to see the magnificent thoroughbred racehorses from Garrison Savannah stables taking their morning swim at nearby Pebbles Beach. Late morning, we called by Hunte’s Gardens, near the centre of the island, where the remarkable Anthony Hunte has nurtured a botanical wonder in a natural sinkhole. Lunch at laid-back Fisherman’s Pub, up the west coast at historic Speightstown, was followed in the evening with a lovely dinner at Hazel’s place.
Monday 28 March: We rose very early (0430!) to reach Cave Hill around 0500, where we joined CERMES colleagues (Micaela, Mia, Joe, Hazel) in two 4×4 vehicles – suitable for traversing the rough tracks just after sunrise – to reach Walker’s beach at low tide, when ‘fresh golden’ Sargassum is left stranded. Three variants of Sargassum are mixed together in the beached jumble stretching away as far as the eye can see. To monitor the beach, a team of four (plus us) staked out a 100-m transect, which was surveyed with a drone, while samples of Sargassum were sifted for the ratios (by volume) of the three variants. Yanna, Micaela, Joe and Mia used a field spectrometer to record the spectral signature of Sargassum, ground-testing what we see from satellites. In the afternoon back at CERMES, Bob and Hazel met with Sanola Sandiford (MPhil student intern with the Caribbean Institute for Meteorology & Hydrology) to discuss modelling of atmospheric pathways and deposition of the volcanic ash which potentially fertilized Sargassum in April 2021 following a major volcanic eruption on the nearby island of St Vincent.
Tuesday 29 March: Yanna returned to the field with Micaela, Joe, Makeda Corbin, Mia and Kristie Alleyne, to monitor Sargassum in Conset Bay where the team undertook a drone survey and took some great aerial videos and photos, we applied a refined protocol to collect data with the field spec, having learnt lots at Walker’s Beach. Hazel meanwhile took Bob snorkelling at dawn in Carlisle Bay, where green turtles grazed on seagrass as a charismatic spotted eagle ray cruised by – memorable experiences! Later on, we finalised some collaborative work to align different types of Sargassum forecast and worked on other research papers. Meanwhile, it was clear from the CERMES ‘lookout’ that Sargassum was drifting northward off the west coast. On mid-morning return, the team therefore headed offshore to sample this drifting Sargassum, directed from the CERMES rooftop by Hazel, in between celebrating her birthday with colleagues Henri Valles, Amina Desai and Shelly Ann Cox! In the evening the fieldwork team went for a well-earnt dinner together at Worthing Gap, while Bob flew (sadly!) home.
Wednesday 30 March: On Wednesday morning, Yanna took the opportunity to go for an early morning scuba dive with Micaela to see the wonderful biodiversity that the Bajan coast is home to; Carlisle Bay is full of wonderful fish, coral, and shipwrecks. She spent the rest of the day at CERMES, processing and sorting field data in the office, rounding off the day with a wonderful dinner with Hazel.
Thursday 31 March:
Yanna spent the morning at CERMES soaking up the remaining time with colleagues and finishing up some data sorting, before heading off back to the UK where it was 1 degree and snowing on arrival (take me back to Barbados please!).
Reflections: This was a memorable experience for both of us, scientifically and culturally. Hazel and CERMES colleagues – plus many others across the island – showed us such hospitality, helping us to build our knowledge and understanding of this special tropical environment. As our world opens up again and as Sargassum continues to challenge the region, there is so much more to do on and around this wonderful island, growing our collaborations and friendships as we go along.
by Bob Marsh & Yanna Fidai
5 April 2022