Impacts of sediment and fishing stress on coral reefs of Saint Lucia

Saint Lucia has a series of Marine Protected Areas (MPAs) that were established over 25 years ago and have been successful at increasing the biomass of reef fishes. However, coral has continued to decline in Saint Lucia, both in and out of MPAs, largely because of sediment runoff. As part of this long-term project in Saint Lucia in partnership with the Soufriere Marine Management Association, we continue to monitor coral reefs to better understand how they are affected by sediment runoff and protection from fishing, and to develop increasingly successful management strategies.

Accurately measuring sedimentation rates on Eastern Caribbean coral reefs

The islands of the Eastern Caribbean are volcanic and steep. Activities that remove natural vegetation (such as agricultural development and unpaved roads) lead to increased erosion in the watershed, and high sedimentation rate in coastal ecosystems. While we know that excess sediment is detrimental to coral, actual sedimentation rate has been historically quite difficult to measure accurately. During our 2018 Eastern Caribbean expedition, we deployed relatively new devices that measure sedimentation rate more accurately than possible in the past. These allowed us to quantify sedimentation rate at 45 reef sites that span a range of coastal development, in Saba, Saint Eustatius and Saint Lucia. Thanks to National Geographic for funding that made this project possible! We are now working on finding funds to sustain these sediment monitoring projects and eventually expand them to other islands.

Linking service-learning field courses with community partners throughout the Eastern Caribbean

One difficulty in managing marine protected areas (MPAs) is that there is often not enough time, resource and funding for robust monitoring programs which allow managers to understand how the protected ecosystems are changing over time, yet this information is critical to make good management decisions. On the other hand, many marine biology students want to gain field experience and need practice surveying coral reefs and other marine ecosystems. Chantale has led many field courses in the Caribbean, in which students learn how to identify reef coral, invertebrates and fish, and how to conduct various reef surveys. Since 2018, she has teamed up with various community partners so that surveys completed by students in the courses are done in areas that are especially worthwhile for marine park managers, and to analyze and present results to these managers. We are now working on building new partnerships throughout the Caribbean, to facilitate field courses being held in various locations to collect data in many more places.

Our work platforms

We work in a number of ways, but sailing is often a great way to get to our field sites while carrying our home and equipment, in a much more sustainable way that we could do by flying from site to site. S/V Maia Sophie allowed us to carry out our 2018 Expedition. Eliot Thorne has designed a vessel which we hope to build in the future, to allow us to carry out many more expeditions.

Our past vessel and work platform, Maia Sophie

Our future vessel, designed by Thorne Yacht Designs

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