Monday 14 December 2015

Jelly Farm Meeting 2nd – 3rd Dec 2015, University of Oslo

Some of the JellyFarm team met at the University of Oslo this week to discuss the progress of the workpackages with a particular focus on workpackage 2.  Andrew Sweetman (IRIS), Kate Boccadora (IRIS), Alessio Gomiero (IRIS), Kathy Dunlop (IRIS), Elizabeth Alve (University of Oslo), Silvia Hess (University of Oslo) and Katja Guilini (University of Gent) attended the meeting. 


Silvia Hess, Katja Guilini, Kathy Dunlop, Elizabeth Alve, Alessio Gomiero

Workpackage 2 focuses on the quantifying interactions between aquaculture and jelly-falls on organic matter cycling in fjord sediments.  It is hypothesis that organic loading from aquaculture and jelly-falls reduces the ability of benthic communities to process organic material in Norwegian fjords.  Isotope tracer studies will be used to quantify the transport of organic material through the benthic food web.  This will involve the isotopic labeling of jellyfish.  This is a very new technique and contact has been made with Berlin Aquarium to help with the supply for live jellyfish for the experiment.  An experimental plan for labeling the jellies was agreed upon and progress was made towards planning the full experiments on organic matter cycling for the Summer.

Workpackage 5: Scavenging Processes at jelly-falls

Workpackage 5 aims to examine the factors affecting scavengers feeding on jelly-falls.  This is important as previous work has shown that scavengers play a major role in utilizing and removing jelly-falls in the benthic fjord environment.  We will focus on two research questions:

1.     Are scavengers deterred from consuming very large jellyfalls due to a high concentration of noxious sulphides and ammonium released by decaying jelly-falls?

2.      What is the impact of organic food supply on the scavenging of jelly-falls?

Findings will determine under which conditions the removal of jelly-falls by scavengers are  maximized. Understanding this in relation to fish farms stresses will be particularly valuable to manage the placement of fish farms to help minimize jelly-fall impacts. 

The scavenger studies will be conducted using a deep sea lander equipped with a Nikon D7100 SLR contained in a deep sea underwater housing viewing a jelly-fall bait.  The camera will take time lapse images of scavengers feeding on the bait. 


The scavenger camera lander was assembled at IRIS to determine the appropriate camera settings and also the image field of view within which the jelly-fall bait will be placed.   Some lander deployments will use a large mass of jellies (10 – 20 kg) to simulate an extensive jelly-fall event.