Lurefjorden Catching Jellyfish. 11th June 2016

The RV Solvik returned to Lurefjorden to catch Periphylla jellyfish to use as bait for the deep-sea scavenger lander cruise in Sognefjorden.  

60 Periphylla were caught on Saturday evening and Sunday morning near Hundvin, Lurefjorden.  20 Periphylla were also dissected for their gonads and sensory organs for Graihagh Hardinge at the Natural History Museum, London to help with ageing  Periphylla.  

Jellyfish Bloom Symposium

The 5th International Jellyfish Bloom Symposium was held at Barcelona aquarium this June.  Andrew Sweetman, Kathy Dunlop and Paul Renaud chaired a session on `Post-bloom impacts on the marine environment´.
Some of the first results from the JellyFarm Project were presented in the oral presentations:

Paul Renaud, Kathy Dunlop and Andrew Sweetman at Barcelona Aquarium for the Jellyfish Bloom Symposium.

Andrew Sweetman:  Jellyfish decomposition at the seafloor can rapidly alter biogeochemical cycling and substantially modify carbon flow through benthic food-webs.

Kathy Dunlop:  Experimental flume studies into the modification of benthic booundary layer flow by jellyfall carcasses.

A poster was presented on describing the JellyFarm Project by Paul.  

Kathy also presented a poster on the deepest salp fall recorded during a cruise on the RV Sonne in Equatorial Pacific.  This work describes how the troughs created by experimental deep-sea mining were concentrating carbon input to the abyss from salp falls.  

Large Jelly Fall in the Flume

A large jellyfall is created in the NIOZ flume using mimic jellyfish.  The jellyfish cover 1/4 of the surface area of the experimental flume space. 

Freshly prepared mimic jellies 

NIOZ adv sampling the fluid velocity and turbidity around the mimic jellyfall. 

NIOZ Cheesecake Bakeoff

A bit of baking as a break from the flume.  Even better when everyone at NIOZ can benefit and an opportunity to say thank you for another great visit.  

The competitors

NIOZ Flume

Mimic jellyfish in the flume at NIOZ ready for some profiling to examine the effects of jellyfish carcasses on fluid dynamics.  

Acoustic Doppler Velocimeter collected data on the flow velocities around a mimic jellyfish 

Flow velocities are being measured around mimic jellyfish in the NIOZ flume to determine the effect of the fall of jellyfish carcasses on the benthic environment.  Our aim is to create flow conditions similar to those found in the deep fjords of Norway inside the flume (slow flows between 2 and 10 cm per second).

The Acoustic Doppler Velocimeter (ADV) is on a robotic arm that allows velocity profiles to be made all around and above the jellyfish carcass.  

Artificial Jellyfish Production

Artificial Jellyfish Flume Experiments

The effect of jellyfish carcasses on fluid dynamics at the seafloor has not been investigated.  Therefore, in April Kathy Dunlop is conducting experiments in flume at the Royal Netherlands Institute of Sea Research (NIOZ).  

First the board on which to place the artificial jellyfish (made of moulded agar) was made and an artificial jellyfish tested in the flume to ensure that it didn't float.

Creating the experimental board to insert into the flume. 

First artificial jellyfish in the flume