Gear and methods are developed for sampling at mesopelagic depths

Monday 23 Nov 20

Researchers from work page 2 (Survey and sampling technology development) presented their latest results at the MEESO annual science meeting.

In work package 2 the effort to improve our ability to quantify and measure mesopelagic components is underway. Most of the partners have so far focused most of their effort under this work package on deploying instruments to mesopelagic depths. 

The primary aim has been to collect acoustic data at relatively short ranges, but work is either implemented or under way that combines the acoustic data with imagery for improved identification of acoustic targets. 

In addition some work has focused on improving theoretical scattering models for mesopelagic scatterers, through improved parametrisation or validation based on in situ measurements, but also by enabling easier access to model results for non-specialists. 

Two partners have also either developed new scientific sampling gear, or modified existing sampling gear to provide more comprehensive data, by combining trawls with optical and acoustical sensors. One of the central problems when it comes to sampling the mesopelagic, is that the presence of our gear at mesopelagic depths usually represents a major disturbance. The work package has a task dedicated to quantifying the effect these disturbances have on the parameters we attempt to estimate, and also here different experiments and data collections are underway. 

Since the data collection in work package 4 (Mapping of mesopelagic resources) depends on some of the methods and equipment developed under work package 2, we have several deliverables and milestones due next year, so in the remainder of 2020 and in the early months of 2021 the work package 2 partners will focus on arranging workshops and producing reports on mesopelagic sampling methodology.


Thor Klevjer, Institute of Marine Research,
Coordinator of MEESO work package 2