Global expansion of jellyfish blooms: Magnitude, causes and consequences (NCEAS Project)

Welcome to the homepage of the Jellyfish Blooms Working Group.

A list of contributors to the jellyfish database known as JEDI can be found here.

Relevant links

A second synthesis paper in PNAS is available here.

Our first synthesis paper was published in Bioscience.

Read the related NY Times article.

Check out Smack Talk, the blog of the NCEAS Jellyfish Working Group, to find out about upcoming events.

Also check out issue 3 of The Tentacle Times, a letter to update the community on progress being made by the Jellyfish Working Group.

The previous issue can be found here.


Jellyfish are an important and often conspicuous component of oceanic food webs. During the past several decades, dramatic spatial increases and temporal shifts in jellyfish distributions have been reported around the world. Undoubtedly there are associated ecological ramifications such as food web and biogeochemical pathway alterations. Moreover, socio-economic impacts include damage to fisheries, industry and tourism. However, reports have remained local in scope, and scientists agree that a composite understanding of the extent of the problem is still lacking. The bottle-neck is the lack of synthetic analyses across marine ecosystems, due to the present fragmentation of data sources. This proposal will provide a global synthesis of reports of jellyfish abundance to achieve four main objectives:

  1. to examine the hypothesis of a global expansion of jellyfish blooms, and to explore the possible drivers for this expansion
  2. to examine the effects of jellyfish blooms on the ecosystem, addressing in particular, carbon cycling, and food webs
  3. to identify current and future consequences of jellyfish blooms for tourism, industry and fisheries, including ecosystem-based management on regional and global scales
  4. to notify the public at large of the project results.

The centerpiece of this project will be a scientifically coordinated global jellyfish and environmental database based on already identified datasets from coastal, estuarine and open-ocean regions. This is a two year project and meetings will be a combination of plenary and specific group level sessions involving data acquisition and statistical analyses, global synthesis of trajectory maps of regional jellyfish blooms, generation of conceptual diagrams of the role of jellyfish in biogeochemical cycles and food webs, and discussions relating to the socio-economic ramifications of jellyfish blooms. Discussions surrounding the framework of the database and identifying deficiencies and additional data requirements will take place in the first meeting. The deliverable products addressed in the proposal include:

  1. at least six group publications submitted to major scientific journals in addition to several articles in the popular literature
  2. several new process-oriented proposals to be submitted to US and international funding bodies based on hypotheses generated from the database
  3. multi-lingual website and blog housed on the NCEAS network including the interactive jellyfish database, and educational information on jellyfish blooms
  4. two public seminars and discussion forums, hosted in Spain and another one facilitated by NCEAS coinciding with one of the meetings
  5. white papers designed for funding agencies and environmental managers identifying research priorities and protocols for monitoring jellyfish blooms
  6. a book detailing the biogeochemical, ecological and societal aspects of jellyfish blooms.