Global experts question claims about jellyfish populations

February 01, 2012

Blooms, or proliferation, of jellyfish have shown a substantial, visible impact on coastal populations - clogged nets for fishermen, stinging waters for tourists, even choked intake lines for power plants - and recent media reports have created a perception that the world's oceans are experiencing increases in jellyfish due to human activities such as global warming and overharvesting of fish. Now, a new global and collaborative study questions claims that jellyfish are increasing worldwide and suggests claims are not supported with any hard evidence or scientific analyses to date.

Dr Cathy Lucas, a marine biologist at the University of Southampton, who is based at the National Oceanography Centre, Southampton was involved in the study, which appears in the latest issue of BioScience (BioScience manuscript # 11-0051.R1). Her co-authors are comprised of experts from the Global Jellyfish Group, a consortium of approximately 30 experts on gelatinous organisms, climatology, oceanography and socioeconomics from around the globe, that includes co-principal investigators Dr Rob Condon, marine scientist at the Dauphin Island Sea Lab (DISL) in Alabama; Dr Carlos Duarte of the University of Western Australia's Oceans Institute and the Instituto Mediterráneo de Estudios Avanzados (IMEDEA) in Spain; and Dr Monty Graham of the University of Southern Mississippi (USM).

The Global Jellyfish Group conducted their work at the National Center for Ecological Analysis and Synthesis (NCEAS), a cross-discipline ecological and data synthesis research centre affiliated with the University of California, Santa Barbara, USA.

"Clearly, there are areas where jellyfish have increased, the situation with the Giant Jellyfish in Japan is a classic example," says Dr Lucas. "But there are also areas where jellyfish have decreased, or fluctuate over the decadal periods." Dr Lucas says understanding the long-term rather than short-term data is the key to solving the question about jellyfish blooms.

Increased speculation and discrepancies about current and future jellyfish blooms by the media and in climate and science reports formed the motivation for the study. "There are major consequences for getting the answer correct for tourism, fisheries and management decisions as they relate to climate change and changing ocean environments," says Dr Carlos Duarte. "The important aspect about our synthesis is that we will be able to support the current paradigm with hard scientific data rather than speculation."

The study highlights the centrepiece of their research collaboration with NCEAS - the formation of a global database called the Jellyfish Database Initiative (JEDI) - a community-based database project that is being used in the global analysis and to test the worthiness of the current paradigm. The database consists of over 500,000 data points about global jellyfish populations collected from as early as 1750, and will be made as a future repository for datasets so that the issue of jellyfish blooms can be continually monitored in the future.

By analysing JEDI, the group will be able to assess key aspects behind the paradigm including whether current jellyfish blooms are caused by human-made actions or whether we are simply more aware of them due to their impact on human activities, such as over-harvesting of fish and increased tourism. "This is the first time an undertaking of this size on the global scale has been attempted but it is important to know whether jellyfish blooms are human-induced or arise from natural circumstances," says Dr Condon. "The more we know, the better we can manage oceanic ecosystems or respond accurately to future effects of climate change. The scientific data exists to answer this question, but it is fragmented in analysis".
-end-
The global analyses using JEDI are currently underway with an anticipated finish date of spring 2012.

University of Southampton

Related Climate Change Articles from Brightsurf:

Are climate scientists being too cautious when linking extreme weather to climate change?
Climate science has focused on avoiding false alarms when linking extreme events to climate change.

Mysterious climate change
New research findings underline the crucial role that sea ice throughout the Southern Ocean played for atmospheric CO2 in times of rapid climate change in the past.

Mapping the path of climate change
Predicting a major transition, such as climate change, is extremely difficult, but the probabilistic framework developed by the authors is the first step in identifying the path between a shift in two environmental states.

Small change for climate change: Time to increase research funding to save the world
A new study shows that there is a huge disproportion in the level of funding for social science research into the greatest challenge in combating global warming -- how to get individuals and societies to overcome ingrained human habits to make the changes necessary to mitigate climate change.

Sub-national 'climate clubs' could offer key to combating climate change
'Climate clubs' offering membership for sub-national states, in addition to just countries, could speed up progress towards a globally harmonized climate change policy, which in turn offers a way to achieve stronger climate policies in all countries.

Review of Chinese atmospheric science research over the past 70 years: Climate and climate change
Over the past 70 years since the foundation of the People's Republic of China, Chinese scientists have made great contributions to various fields in the research of atmospheric sciences, which attracted worldwide attention.

A CERN for climate change
In a Perspective article appearing in this week's Proceedings of the National Academy of Sciences, Tim Palmer (Oxford University), and Bjorn Stevens (Max Planck Society), critically reflect on the present state of Earth system modelling.

Fairy-wrens change breeding habits to cope with climate change
Warmer temperatures linked to climate change are having a big impact on the breeding habits of one of Australia's most recognisable bird species, according to researchers at The Australian National University (ANU).

Believing in climate change doesn't mean you are preparing for climate change, study finds
Notre Dame researchers found that although coastal homeowners may perceive a worsening of climate change-related hazards, these attitudes are largely unrelated to a homeowner's expectations of actual home damage.

Older forests resist change -- climate change, that is
Older forests in eastern North America are less vulnerable to climate change than younger forests, particularly for carbon storage, timber production, and biodiversity, new research finds.

Read More: Climate Change News and Climate Change Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.