NICO Science Expedition to the Dutch Caribbean
December 13th marked the beginning of an incredibly exciting and ambitious research expedition organized by the Royal Netherlands Institute of Sea Research (NIOZ) and NWO-Science (ENW). On that day, NIOZ’s research vessel RV Pelagia set sail from Texel, The Netherlands, and will be at sea for the next seven months conducting a multidisciplinary scientific expedition entitled “Netherlands Initiative Changing Oceans (NICO)”. Aboard the vessel are 100 scientists (spread out over 7 months) from a wide range of disciplines and representing 20 national and international scientific organizations. Over the coming seven months, the ship will visit five ocean provinces (North Sea, Atlantic Ocean, Caribbean Sea, Gulf of Mexico and Bay of Biscay) and collect research data on such diverse subjects as foraminifers, viruses, coral reefs and migratory birds.
The NICO expedition aims to provide the Netherlands with a better understanding of changing seas and oceans, and data collected “will help answer fundamental questions in marine science and help develop new technical solutions which are essential for planning and making decisions about our future livelihoods” (NIOZ, 2017). An extra motivation for the expedition is the policy document 'Oceanennotitie' which was published by the Dutch Government last spring. This document emphasizes the importance of healthy and resilient oceans to The Netherlands and outlines 30 policy ambitions with regard to the sustainable use of oceans. There are twelve stages to the expedition, some lasting a few days whilst others will take several weeks. Four of these stages (stage 3 to 6) will take place in Dutch Caribbean waters and collect invaluable data for the management of our islands’ marine resources.
During the Southern Caribbean leg of the expedition, the mesophotic reefs (i.e. reefs below 30 m depth) of Bonaire, Curaçao and Aruba will be the focus of the expedition’s first research project within the Dutch Caribbean (Stage 3: Chief Scientist: Petra Visser – UvA; Co-scientist: Fleur van Duyl-NIOZ). The goal of this project is to explore the deep reefs along the coast of the ABC-islands, sample and investigate the fields of cyanobacteria that have been observed in front of Kralendijk and detect where onshore ground waters enter the offshore environment . If seepage areas of nutrient rich water/pollution sources can be found, they can be mapped and managed. Mesophotic reefs are still mostly unexplored because of their remoteness or inaccessibility, but are believed to be of great ecological value, providing offspring to shallow reef communities that are more prone to climate change and pollution. One focus of this project is cyanobacterial mats; the hypothesis here is that submarine groundwater discharge (SGD) or runoff from the land causes eutrophication of waters and results in the proliferation of cyanobacterial mats. The research team will use photographic and acoustic mapping to investigate the bottom topography on both the leeward and windward side of the islands. Water samples will be taken to detect the seepage of nutrients from ground water and samples from cyanobacterial mats will be collected to investigate their composition and functioning. The intention is to investigate putative effects on the coral reef ecosystem like adding more nitrogen to the system by nitrogen fixation by the cyanobacteria, toxicity of the mats to other organisms, and the production of organic matter. This project will provide vital data to ensure efficient waste water management on the islands and consequently improved health of the coral reefs.
The second research project of the expedition in the Dutch Caribbean (Stage 4: Chief Scientist: Femke de Jong – NIOZ; Co-scientist: Meike Scheidat-WMR) takes place between Aruba and St. Maarten and investigates how eddies in the Caribbean influence the occurrence of pelagic megafauna, more specifically cetaceans, turtles, large fish species (sharks, sunfish) and sea birds. Eddies are known to affect and transport plankton communities. However, there is very little research that has explored both the impact of eddies and their oceanographic characteristics on the distribution and occurrence of organisms at a higher trophic level. Visual surveys will be used to assess the occurrence of pelagic megafauna. Passive acoustic monitoring will help monitor the presence of deep diving cetacean species. Eddies are known to greatly impact ocean currents and local sea level, but it is unclear what processes govern the lifecycle of these eddies. Sailing northeastwards from Aruba to St. Maarten, the project’s team will there try to locate an eddy and perform a detailed hydrographic survey of it and its ambient Caribbean waters. The index of productivity and nutrient availability of the waters inside and outside the eddy will also be measured. This research project will not only gather important information on the hydrography and cetaceans and other megafauna in the Greater Caribbean, but will help provide insight as to how global warming will impact these species. Eddies in the Caribbean have surface waters that are roughly 4 ̊C warmer than the ambient ocean, and lack of nutrient availability inside these eddies and altered biological activity may provide insight in what to expect in the future.
During the Northern Caribbean leg of the expedition, two research projects will focus on the Saba Bank. Scientists have a special interest in this large submerged carbonate platform because it is still relatively pristine thanks to its remoteness and therefore offers the chance to monitor the effects of climate change in the Caribbean Sea. While a number of research projects have explored the shallower parts of the bank, very little is currently known about the bank’s deep-sea habitats.
The third research project of the NICO expedition in the Dutch Caribbean (Stage 5: Chief Scientist: Gerard Duineveld – NIOZ; Co-scientist: Furu Mienis-NIOZ) focuses on Saba Bank’s deep-water environments (100 m and beyond). The main goals of this project are to describe the biodiversity of the Saba Bank’s deep slopes, including the benthic habitats of engineering species, macro- and micro fauna and the composition of the fish community, as well as identify environmental conditions that influence these habitats and fauna. The expectation is that the bank’s deep flanks are covered with sponges and corals that provide important habitats for mobile species like commercial fish and crustaceans. The project team also anticipates the discovery of multiple species yet unknown for science and the Dutch Caribbean islands. In order to map the Saba Bank’s deep-sea habitats and establish their function as fish habitat, video transects will be made along the bank’s slopes with different characteristics (steep vs gentle), from shallow water depths (100 m) to the deep-sea. Along the same transects Conductivity Temperature Depth (CTD) casts will be carried out to identify environmental conditions that are influencing these habitats, and water samples will be collected for geochemical analysis (suspended matter, inorganic nutrients) as well as environmental DNA (eDNA) for fish and macro-and microfauna. This data can be used to develop a sustainable management plan for the Saba Bank.
The last research project of the NICO expedition in the Dutch Caribbean (Stage 6: Chief Scientist Fleur van Duyl – NIOZ; Co-Chief Scientist Erik Meesters-WMR) focuses on how the net capability of physiognomic and hydrodynamic characteristics of the Saba Bank (e.g. bathymetry) affect benthic habitat distribution patterns and the biogeochemical functioning of different reef ecosystem habitats (e.g. coral-, macroalgae-, CCA-, gorgonian, rubble-, sponge and sand dominated habitats). The 2016 Saba Bank expedition by NIOZ revealed a multitude of ecosystems that thrive mostly in the mesophotic realm (>30 m deep), however much is still unknown about the Saba Bank’s benthic communities and their role in reef ecosystem functioning. The research team plans on setting up seven benthic stations across the bank from which a number of measurements will be made. For example, net calcification in distinct habitats at different depths will be measured with the use of a NIOZ benthic water gradient sampler. Eddy covariance lander will be used to quantify net primary production and community respiration. Benthic surveys with underwater cameras and multibeam will be conducted to expand the mapping of different habitats, bathymetry, and bottom roughness on the Saba Bank. In addition, during the St. Maarten - Saba Bank transit via Saba an St. Eustatius and the transect over the Saba Bank and back to St. Maarten, eDNA samples will be taken to confirm the presence of specific shark species. Furthermore, the research team will use photographic and acoustic mapping to map the largely inaccessible and therefore unknown windward sides of both Saba and St. Eustatius.
You can track the journey of RV Pelagia here: https://www.marinefacilitiesplanning.com/programme/map
This news-item was published by DCNA in BioNews 11-2018.