IMIS

In this Belgian EMBRC Joint Development Activity, funded by FWO, we tested deployment of Autonomous Reef Monitoring Structures (ARMS) in coastal dynamic environments and assessed different retrieval strategies in a methodological study. ARMS are typically deployed in shallow and sheltered areas, like ports and marinas, and are easily accessible with divers. Deploying further offshore, at greater depths and in dynamic environmental conditions with high currents and limited visibility, complicates deployment and retrieval strategies by divers. To this end we explored two set-ups to anchor ARMS in an offshore windmill farm: a concrete anchor and a tripod mounted with a float and acoustic release system. Each set-up was mounted with 3 replicate ARMS units, with each replicate unit undergoing a different retrieval treatment. One replicate unit was left uncovered and winched on board of the RV using the vessels’ A-frame, one replicate units was covered with a crate by a diver before being winched on board, a third replicate unit was covered by a mesh and crate, cut loose from the anchor or tripod by a diver and brought to the surface by hand. Motile and sessile fractions were identified morphologically and subsequently used for the development of sequencing protocols for Oxford Nanopore Technologies (ONT). 

The JDA will deliver SOPs related to the operational and dive work at sea, lab processing, including the construction of a standardized photo set-up, subsequent morphological analysis and sequencing using ONT.