Is there enough scientific evidence to claim that global jellyfish populations are increasing?

M. Harlow \ Oceans First, Issue 1, 2014, pgs. 26-36.

Download PDF


Jellyfish have been highlighted in the media as of late for increasing in population. This perception however is based on specific sightings in certain locations, and not sightings on a global scale. Jellyfish tend not to be seen as a welcomed creature in human society due to their ability to sting swimmers, and clog fishing nets.  This paper aims to review studies on jellyfish characteristics, and past population trends in order to answer the question are jellyfish populations really rising? The conclusions of past studies remain uncertain due to a lack of historical data, but have found that jellyfish could indeed be more likely to survive in warmer, and more hypoxic waters than other organisms. Others have found that the speculated rise in jellyfish populations could be part of a decadal oscillation. In conclusion there is no consensus as to whether or not global jellyfish populations will rise. The public must become better informed on current ocean conditions and data must continue to be collected about the populations and habitats of jellyfish.