Epibenthic sledge with Camera system
The Epibenthic sledge or EBS is a sledge which is towed along the bottom of the sea at any depth. It has a stainless steel metal frame with two nets build in. At the front is has two doors, which are operated by a mechanical leaver, which keeps the doors closed in the water and only open the doors when the EBS is on the seafloor. This way you always know the animal in your nets are coming from your actual tow and not from the water column when the EBS is on its way up or down. It is designed to collect very small animals, which gets pushed up from the seabed by its bow wave or live just above the sea bed. It can be deployed to any depth up into the deep sea to 3000 – 4000m water depth.
The biggest disadvantage of such system is that it is especially in deep water not easy to estimate when the sledge is on the sea floor and for how long you have dragged it. To overcome this problem our EBS is now fitted with a Deep Water Camera System which is mounted in the front of the EBS filming each tow making it easy afterwards to calculate towing time, identify the substrate the EBS was towed in and to identify any benthic macro fauna, which was not caught in the EBS.
Additional to scale objects on the image, it has two lasers fitted in parallel which makes it posible to scale especailly larger organism like starfishs on the video picture. Also to get information about the water the EBS is towed in, it is now fitted with a stand alone CTD which proviedes information about the salinity, the precise water depth and the temperature of the water. This is used to understand in which enviromental condition the animals are living in.