A Portable Cruising Speed Net: Expanding Global Collection of Sea Surface Plankton Data

Abstract

Plankton are central to planetary ecology, generating 50% of Earth’s atmospheric oxygen and forming the largest system of interconnected life at the base of the marine food chain. Yet, current oceanographic models aimed at predicting global climate change lack high-resolution biological data, emphasizing the need for innovative approaches to collect plankton biodiversity and distribution data over larger spatial, temporal, and taxonomic scales. The significant number of boats, ranging from small sailing yachts to large commercial vessels, that ply the world’s oceans every day could help scientists collect thousands of valuable plankton samples. Traditional Plankton Nets (TPN) are not suited to the speed of a recreational craft cruising in the high seas (i.e., at speeds >2 knots). We developed and validated the efficiency of a lightweight, easily deployable Cruising Speed Net (CSN) that enables the collection of ocean surface micro- and mesoplankton at speeds up to 5 knots. Field testing was conducted during two distinct research cruises along coastal and oceanic latitudinal gradients (SSV Robert C. Seamans in New Zealand and RV Investigator in the south-east Indian Ocean). DNA metabarcoding performed on the collected plankton samples showed the TPN and CSN yielded identical sequence-based diversity at low speed, with the CSN also effective at higher speed for characterizing latitudinal distribution of plankton communities. The CSN represents a valuable new tool for expanding the global collection of plankton data.

Assessing the performance and efficiency of environmental DNA/RNA capture methodologies under controlled experimental conditions

“…In this experimental study, we have showcased a multidisciplinary approach to measure the efficiency of different filter membranes for the capture of eDNA and eRNA (presented as whole cells, broken cells and naked NAs) from marine water samples. The results (Verdier et al, 2021;von Ammon et al, 2020;Wood et al, 2019).…”

“…The evidence that coarse pore‐size membranes might perform as well as smaller pore‐size filters for capturing different fractions of NAs from water has important practical implications for monitoring and surveillance programmes. Efficient sampling of NAs from varied aquatic ecosystems routinely involves concentration of heterogeneously distributed genetic material across large areas or water volumes (Verdier et al, 2021; von Ammon et al, 2020; Wood et al, 2019). This crucial aspect of the workflow is quite challenging, entailing tedious, time and resource‐intensive human effort.…”

“…whole cells, partial cells, naked DNA and RNA). Most studies to date rely on the collection and isolation of environmental samples and the use of metabarcoding for comparative analyses of species richness among molecular methods and traditional observations (Deiner et al, 2015; Deiner et al, 2018; von Ammon et al, 2020). The use of environmental samples, however, is often restricted to inherent properties that cannot be effectively controlled such as turbidity and unknown inhibitors.…”

A Rapid Molecular Assay for Detecting the Mediterranean Fanworm Sabella spallanzanii Trialed by Non-Scientist Users

“…For example, the sampling routine can be greatly simplified by using passive sampling devices, that capture eDNA onto a sampling matrix while being deployed in the water (Kirtane et al, 2020;Bessey et al, 2021). As an alternative to time-consuming bulk/planktonnet water sampling and subsequent filtration (von Ammon et al, 2020;Bowers et al, 2021), in situ filtration systems with selfpreserving filter packs are now available on the market (Thomas et al, 2019). For the DNA extraction step some promising tools are reported in the literature to be fast, produce high-quality DNA extracts and utilize equipment that can be battery-operated such as the Pretty Damn Quick Extractor (PDQeX, MicroGem), which has been successfully used in low-resource settings for pathogen detection (Boykin et al, 2019).…”

Plankton Planet: A frugal, cooperative measure of aquatic life at the planetary scale

“…This requests uncomfortable sailing operations impacting the cruising speed, and it was identified as the primary limiting factor for denser sampling. We have therefore been working on the design of new miniaturized high-speed nets (von Ammon et al, 2020;Meŕiguet et al, 2022), inspired by our successful experience during the Tara Pacific expedition (Gorsky et al, 2019), as well as simple manual pumping system allowing aspiration of seawater at cruising speed, followed by filtration through a small net system installed on board. The latter device has the advantage of being able to collect pristine water that can also be used to extract DNA/RNA from the smaller plankton size fractions enriched in bacteria, archaea and viruses.…”