Other than Diana Nyad, most people don’t wonder how many jellyfish are in the world’s oceans and where the highest concentrations of them might be. In fact, they wouldn’t be able to get those questions answered anyways … until now.
The Jellyfish Database Initiative, or JeDI, is the first scientifically-coordinated worldwide database of jellyfish records. It’s the result of a new international study led by marine biologist Dr. Cathy Lucas and researchers at the University of Southampton. In the study, Dr. Lucas thanks the new JeDI masters.
The successful development of this first global-scale database of jellyfish records by the Global Jellyfish Group was due, in large part, to the incredible generosity of members in the international jellyfish research and wider scientific communities.
The database holds over 476,000 items on jellyfish and other gelatinous organisms and is housed at the National Center for Ecological Analysis and Synthesis (NCEAS) USA at the University of California, Santa Barbara.
Using data from the JeDI, Dr. Lucas and the researchers showed that that jellyfish and other gelatinous zooplankton exist in all of the world's oceans. The highest concentrations are in the mid-latitudes of the Northern Hemisphere, especially in the North Atlantic Ocean where dissolved oxygen and sea surface temperature are the major factors in jellyfish population size.
A critical function of the JeDI will be to track the numbers and concentrations of jellyfish as both harbingers and effects of climate change. Dr. Rob Condon of the University of North Carolina Wilmington is one researcher using it for that purpose.
If jellyfish biomass does increase in the future, particularly in the Northern Hemisphere, this may influence the abundance and biodiversity of zooplankton and phytoplankton, having a knock-on effect on ecosystem functioning, biogeochemical cycling and fish biomass.
When you put it that way, perhaps we should be grateful there are JeDI masters making sure we can still be stung by jellyfish.
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