Jellyfish ecology

Swansea University’s Department of Biosciences has received funding worth £145K from the Esmée Fairburn foundation for a two year project entitled "Jellytrack: connectivity of jellyfish populations"

The project, managed by Swansea University researcher Dr Sabrina Fossette, will employ an innovative approach at the interface of molecular biology and state-of-the art tracking technologies to investigate jellyfish distribution and movements over different geographical scales, revolutionising our understanding of jellyfish ecology.

Over recent years the abundance of jellyfish blooms has increased, with growing concern that their overall ecosystem impact, both positive and negative, and consequently their socio-economic importance may similarly increase.


Dr Fossette (pictured) explains: “The conservation implications of jellyfish taking over the oceans are clearly huge and dire. For example, jellyfish are known to eat fish larvae and eggs, regulate the abundance of plankton, and impact negatively on aquaculture ventures, such as mussel farms.

“However, not all interactions are negative, some juvenile fish can enhance their survival rate by sheltering underneath jellyfish umbrellas. Also the emerging demand for jellyfish products in the far east are spawning new jellyfish harvesting industries.”

Despite the alarming prediction that jellyfish may be taking over the oceans, there is very little known about the ecology of jellyfish, largely because of a lack of targeted research.

Professor Graeme Hays, Principal Project Investigator alongside Dr Pat Lee, based in the Department of Biosciences, said: “The Jellytrack project will help to address this lack of data and enable the prediction of future changes in the extent and occurrence of jellyfish blooms under different scenarios of global changes.”

The project will build on previous research undertaken by The EcoJel Project, a four year collaborative project between Swansea University and University College Cork (Ireland), funded by the European Union Regional Development Fund (ERDF) under the Ireland Wales Programme 2007-2013 - Interreg 4A, which used aerial surveys to identify huge bloom sites for jellyfish along the Welsh coast.


There will be two elements to the research which will focus on giant barrel jellyfish (pictured), which can weigh more than 20kg and are seen in abundance in the Irish Sea where every year huge blooms of tens of millions of jellyfish are recorded.

Firstly, electronic tags will be fitted to individual jellyfish allowing their movements to be followed and assess the extent of individual movements for periods of several weeks or months. Drogues and current metres will also be used to ascertain whether jellyfish are carried by currents or if they actively swim to maintain their position.

Secondly, the fine-scale genetic structure of barrel jellyfish will be examined by employing non-destructive methods to take DNA samples from tagged jellyfish. Comparisons will then be analysed and compared with previous samples taken from jellyfish located in Rosslare (Ireland) and La Rochelle (France) revealing the genetic connectivity between different locations around the Irish Sea.

Professor Hays concludes: “Results of the project will improve local, regional and national management of coastal waters through a better understanding of the dynamics of jellyfish blooms and will notably be used to inform management authorities in the UK of the likely threats imposed by blooms of jellyfish in the UK waters.”

Visit the project website for further information.

For further information on the Department of Biosciences, based in the School of the Environment and Society at Swansea University, visit

This news item has been generated by Katy Drane, Swansea University Press Office, Tel: 01792 295050, email: