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. 

Fish Farm Visit

Thursday 5th November 2015

The Jellyfarm project is studying the interactions between aquaculture and jellyfalls on organic matter cycling in fjord sediments.  Therefore, on the way to deploy the second sediment trap in the Masfjorden we stopped to visit a local fish farm.

An underwater camera system is used to monitor the salmon in the fish farm.

Masfjorden Sediment Trap Deployment

Friday 6th November 2015

Once deployed the Masfjorden sediment trap will remain in position collecting data on organic flux until August 2016.  Sample bottles will be collected approximately every 2 weeks.  

 Deploying the sediment trap from the RV Solvik. 

The final float about to be deployed

Lurefjorden

Wednesday 4th November 2015

Lurefjorden has been found to contain the largest population of Periphylla periphylla jellyfish of any fjord.

Today the Lurefjorden sediment trap was redeployed.

 Sediment trap being lowered to attach to the weights which will take it to the seafloor.

Carefully lowering the sediment trap into the Lurefjorden.

On our way for an evening at sunny Siem. 

Retrieval of the Masfjorden Sediment Trap

Tuesday 5th November 2015 

The Masfjorden sediment trap was initially located using the echo-sounder and a ROV from ROVas was deployed to help retrieve the sediment trap.

The sediment trap floats were visible in the echo-sounder.

ROVas vessel equip with ROV 

Leon made a hook and line for the ROV to secure the sediment trap.  The ROV would attached it using the manipulator arm.  Once attached the sediment trap could be lifted using Solvik´s winch.

Discussing the retrieval plan 

The sediment trap was successfully retrieved and was ready to be serviced for redeployment. 

Andrew waiting for the Masfjorden sediment trap to be lifted by the winch.  

JellyFarm Cruise 2nd - 6th November 2015

The second JellyFarm cruise of 2015 set out to retrieve, service and redeploy sediment traps in the Lurefjorden and Masfjorden.  Both traps had been unfortunately caught by a trawling vessel.  Making these redeployments will ensure that minimal data is lost from the sediment trap study. 

The JellyFarm sediment trap study aims to quantify jellyfish organic material falling to the deep fjord seafloor ecosystem.  Organic material derived from jellyfish have an enriched  isotopic δ13C signature compared to phytoplankton and zooplankton.  To study the affects of organic material entering the benthic environment from jelly fall events, sediment traps were deployed in the Marsfjorden, a fish dominated fjord ecosystem (The name Marsfjorden means “the one full of food ie.  fish”) and the Lurefjorden, a fjord heavily populated by the jellyfish Periphylla periphylla. 

The team consisted of Leon Pedersen, Dr Andrew Sweetman (International Research Institute Stavanger (IRIS)) and Dr Catherine Boccadoro (IRIS).  Postdoctoral researcher Dr Kathy Dunlop (IRIS) joins the JellyFarm team from Monterey Bay Aquarium Research Institute, California, where she worked with the Pelagic Benthic Coupling Group. Kathy will work with the JellyFarm project for three years and will specifically focus on the influence of jelly falls on scavenger and fluid dynamics in the fjords.  

Farewell!

The Jelly Farm Cruise 2015 is sadly now at an end!

The end of the cruise with the team at Sævråsvåg. Pictured: Magnhild Torper, Silvia Hess, Graihagh Hardinge, Andrew Sweetman, Leon Pedersen, Elisabeth Alve. 

Over the course of the week a series of deep-sea samples were collected, which will be analysed at various institutions affiliated with the Jelly Farm Project. 

Thanks to everyone who followed us on this journey. 

See you next year for the next Jelly Farm cruise!

Deploying sediment traps in Masfjorden

Solvik in Sævråsvåg

Today marks the final day of sampling for the Jelly Farm cruise 2015! 

The Masfjorden sediment trap was deployed to 480 m. Like the Lurefjorden trap, a new sample bottle will be automatically switched every 14 days, and then the trap collected after a year on the sea floor. Scavenger traps containing mackerel bait were also deployed, as the yo-yo frame yesterday did not haul up any scavengers. The sample net with attached traps brought up a few hagfish, which were bagged and frozen for isotope analysis. 

Priming the acoustic releaser for the sediment trap.

300 kg chain to weigh down the trap.

Deploying the floats for the Masfjorden sediment trap. Pictured: Graihagh Hardinge and Andrew Sweetman.

Successful deployment! Pictured: Andrew Sweetman.

Last night of the cruise!

'Team Dan Gelbart'. PIctured (left to right): Leon Pedersen, Andrew Sweetman, Silvia Hess, Elisabeth Alve, Magnhild Torper and Graihagh Hardinge. 

The team celebrated their last night of the cruise in the Kjelstraumen vertshus and enjoyed some fine dining (in not-so-fine clothing) near to where Solvik was docked in Sævråsvåg.