Results from the MEESO project has been published in the scientific journal Deep Sea Research.
The article presents a method to acoustically sample mesopelagic organisms at depths outside the range of high frequency hull-mounted echosounders.
By placing a forward-facing echosounder on the trawl, the behaviour of species up to 30 m in front of the trawl net were observed and their densities and distribution by depth were estimated. Organisms generally did not avoid the trawl though some larger organisms showed some avoidance as the trawl got closer.
This method is a simple way to gain extra information on the mesopelagic organisms and can be used during acoustic-trawl surveys without adding greatly to the valuable survey time.
Reference
An acoustic method to observe the distribution and behaviour of mesopelagic organisms in front of a trawl
Melanie J. Underwood, Eva García-Seoane, Thor A. Klevjer, Gavin J. Macaulay and Webjørn Melle
Deep Sea Research Part II: Topical Studies in Oceanography
DOI: 10.1016/j.dsr2.2020.104873
Link to the article
Contact
Thor Klevjer, Institute of Marine Research, Norway
thor.klevjer@hi.no