Tuesday, 9 January 2018

New JellyFarm Paper: Scavenging processes on jellyfish carcasses across a fjord depth gradient.


This is the accompanying paper to the recent publication in Nature Scientific Reports. The results described in both papers are from field work in June 2016 in Sognefjorden conducted as part of JellyFarm wkp 5. 

EFFECTS Cruise December 2017

EFFECTS (Examining the Role of Fish-Falls on Ecosystem processes)

The EFFECTS Cruise took place in December 2017 with Andrew Sweetman and Robert Harbour (Heriot-Watt University, Edinburgh), Kathy Dunlop and Paul Renaud (Akvaplan-Niva, Tromsø) and Daniel Jones (National Oceanography Center, Southampton).

The team boarded the RV Johan Hjort (Institute of Marine Research). The destination was Kaldfjorden, a fjord system off the island of Kvaløya, close to Tromsø, Northern Norway.

RV Johan Hjort in Kaldfjorden, Troms

In recent years, Kaldfjorden has been a winter stopover site for a large proportion of the migrating Norwegian spawning herring stock.  The herring have been followed to Kvaløya and Kaldfjorden by killer and humpback whales, made famous in the recent BBC Blue Planet II documentary.

Killer whales in Kladfjorden.(image from bbc.co.uk)

Feeding by whales are suspected to result in high herring mortality and the occurrence of high numbers of herring carcasses on the seafloor. Such a large input of organic material to the seafloor has the potential to significantly impact benthic community functioning.  However, carcasses can be removed by the local scavenging community, reducing the effect of  herring decomposition on seafloor processes.  Knowledge of the scavenging communities in Kaldfjorden is very limited and one of the aims of the EFFECTS project was to assess scavenging rates on herring carcasses.

The Anonyx baited camera lander and a yo-yo camera system were used on the cruise to examine what scavenging communities were feeding on herring carcasses and how quickly.  The yo-yo camera system was used to collect images of the seafloor habitat and to quantify the density of herring carcasses on the seafloor. 

Images of the "Anonyx" camera lander being deployed in the dark waters of Kaldfjorden and the Yo-Yo camera being prepared for deployment.  

5 baited lander camera deployments were made in the Kaldfjorden (3 in the outer fjord and 2 in the inner fjord region).  2 yo-yo camera transects were also conducted in each of the outer and inner fjord regions.  

Ships track during EFFECTS cruise. 

Thursday, 14 December 2017


Nature Scientific Reports publishes work by the JellyFarm team, that provides the first empirical evidence of a energy pathway between jellyfish carcasses and a commercially exploited shellfish species (Nephrops norvegicus).  

Monday, 13 November 2017


The EFFECTS project is in collaboration with WHALE, another Fram Centre Flagship project under the Fjord and Coast Research Area (Effects of climate change on sea and coastal ecology in the north).  

WHALE is led by Angelika Renner from IMR and investigates the impacts of massive winter herring abundances on the Kaldfjorden environment. 

Zoe Walker works on the WHALE project and has contributed the following blog post to describe her work in Kaldfjorden.  

Zoe Walker in action in the field for the WHALE project

I'm a Canadian student on exchange in Tromsø (UiT) from the University Centre of the Westfjords in Isafjörður, Iceland. I am working on my Masters thesis as part of the WHALE project, specifically looking to improve the conceptual understanding of how the migratory shift in Norwegian Spring Spawning Herring to Kaldefjord and the presence of whales is influencing pelagic-benthic coupling and biogeochemistry in the fjord ecosystem during polar night. I am utilizing sediment traps, suspended water samples, zooplankton nets, CTD profiles, and local hydrography to create a baseline for the vertical suspended biomass flux in the area during polar night. I began sampling in early October 2017 and will continue through to early February 2018 to explore how the high abundance of animals affects sedimenting matter in the absence of solar radiation, and what impacts that may have for local fisheries and aquaculture.

EFFECTS. Examining the Role of Fish-Falls on Ecosystem processes.

The EFFECTS project is investigating the role of herring carcasses, arriving in Kaldfjorden (close to Tromsø) due to recent shifts in migration patterns of herring in northern Norway on seafloor processes. Input from herring carcasses will be compared with the effects of inputs from aquaculture and jellyfish blooms studied in JellyFarm. 

This research is important to achieve the sustainable management of economic activities in coastal areas that requires a strong understanding of natural and anthropogenic impacts on the ecosystems.  EFFECTS will combine the use of underwater technology, hydrography and biogeochemical modeling and field sampling.

 Underwater camera technology (Anonyx camera lander) and yo-yo drop camera. 

EFFECTS is in collaboration with two other Fram Centre Flagship proposals weShare (Martin Buiw, IMR) and WHALE (Angelika Renner, IMR).  The project involves research collaborartion from Akvaplan-niva, Institute of Marine Research (IMR), Heriot-Watt University (UK), Norsk Institutt for vannforskning (NIVA) and the National Oceanography Center (UK). 

Monday, 23 October 2017

JellyFarm Project presented in PhD presentation at the annual Norske Havforskeres Forening meeting 18-20th of October 2017.

 Introducing the audience to the JellyFarm project.
 Where our samples for the 2017 experiment come from.
 Explaining the experimental set up.
 The treatment the chambers received.
 What we will hopefully gain from the 2016 and 2017 experiment.
I would like to thank Norges Havforskeres Forening on behalf of the JellyFarm project group for the opportunity to present our research.

Friday, 22 September 2017

Jelly Farm Incubation Experiments

Jellyfish (Periphylla periphylla) weighed to be added to benthic cores

Cores transported to microprofiling climate controlled room 

Microprofiling is conducted right before core processing begins

Elisabeth ready for the next core!  

Hege and Elisabeth core slicing

Anouk removes samples for microbiology analysis

The Jelly Farm team enjoying the beautiful views from the Akvaplan niva Barents Sea Lab, Kvaløya.