English Paper on Ocean Acidification and Abundance of Jellyfish

Ocean Acidification and Abundance of Jellyfish

Jellyfish Resistance against Environmental Stressors Such as Lower pH

There is an existing relationship between jellyfish and low ocean pH and this ensures that they blossom unlike other water creatures. This is supported by the fact that more acidic conditions lead to greater numbers of Jellyfish because they are more resistant to such extreme conditions. Such extreme conditions discourage flourishing of other ocean organisms and in the process, eliminate competition that ensures that Jellyfish flourish and increase their numbers. The tolerance of Jellyfish to low pH makes it possible for their survival and asexual reproduction which increases their numbers tremendously. They are able to acclimate to changing pH levels especially when acidity of the ocean increases, sometimes they deal with such low pH routinely in situations that the weather is unpredictable.

Effects of Lowering pH and Abundance of Jellyfish

Salinity and ocean acidification are caused by human activities and while most jellyfish species would appear to thrive and tolerate wide range of salinity, they may also be affected by it. For instance, in situations that there is low precipitation, increased salinity, may result to grown of more populations of Chrysaora Quinquecirrha medusae in Chesapeake Bay. Increase in numbers of this particular species when pH is lowered is because it aids development and growth of polyps unlike other ocean organisms. Reduction in pH promotes growth of polyps, development of jellyfish starts from eggs to polyps and then to Medusas. For some species of jellyfish like Aurelia Labiata, experienced changes in salinity and acidity may greatly influence reproduction especially when effects of temperature are taken into account. Lowering pH increases reproduction of the species because they are able to keep up with and tolerate adverse condition during reproduction. This ensures that their system support diffusion of oxygen to metabolic tissues. This also motivates their tolerance to carbon dioxide even when ions are transported and maintained in the body. Moreover, studies have suggested that some scyphozoan polyps are able to survive a wide range of salinities and that changes in water acidity may be difficult to predict (Murray 2006).

The moment carbon dioxide dissolves in ocean water it leads to an increase in hydrogen ions and in the process, reduce pH value on the ocean water. Moreover, it also leads to reduction in carbonate ion (CO32-) which is an important form of inorganic carbon because most of marine lives heavily rely on this component to form their calcareous shells or skeletons in a process known as calcification. Scientists have established that concentration of carbonate ions in the ocean determines the possibility of dissolution or precipitation of aragonite and calcite, the two natural polymorphs of calcium carbonate (CaCO3), secreted in the form of shells or skeletons by these organisms (Murray 2006). In most ocean surface waters aragonite and calcite are supersaturated confirming the fact that carbonate ions are abundant, this saturation is vital because it keeps structures of marine organisms intact. The effect of lowering ocean pH is the dissolution of shells skeletons because the ocean turns corrosive in the process, this implies that there will be a reduction in carbonate ions and thus becomes catastrophic to diverse habitat in the ocean. Marine scientists have affirmed that main physiological processes of living organisms living in water are affected, such processes include reproduction, growth and photosynthesis and thereby impacting negatively on the habitat leading to loss of biodiversity (Murray 2006).

Ocean Acidification Effects on Jellyfish Marine Life


It is worth noting that ocean acidification affects majority of marine life as discussed above, but there are certain specifies that are able to flourish in an acidified ocean water. Jellyfish is the particular species that is best suited to prosper in high-carbon dioxide conditions even though they have been described by many as nuisance because of their inability to provide adequate habitat and food for other species in marine environment. Increased acidification of water has been responsible for recent increase in number of jellyfish in most oceans because ocean acidification does not affect reproduction or the formation of their internal structures, as it does for many other forms of marine life (Pitt and Lucas 2014).

Moreover, scientific evidence has supported the fact even though acidification may not contribute fully to the increasing number of jellyfish in oceans; acidification creates an enabling environment for jellyfish to flourish (Pitt and Lucas 2014). As a result of blossoming number of jellyfish, disastrous impacts have been witnessed because increased outbreaks of the species have been responsible for decreasing commercial fish stocks due to competition and predation, as well as harboring various fish parasites.

Scientific studies have established a relationship between jellyfish abundance and ocean pH in oceanic waters because these organisms are known to take advantage of the vacant niches made available by the negative effects of acidification on calcifying (Tills and Coauthors 2016). However, more acidic waters may also affect jellyfish because most of ecosystem possesses great percentage of statoliths which are affected by reduced pH value in the oceans. They are important in balancing the ecosystem to equilibrium reception and thus ensuring that jellyfish flourish and survive to reproduce to great abundance


Ocean Acidification and Booming of Jellyfish

Studies have established that jellyfish tend to increase in numbers and boom in oceans characterized by overfishing, acidification from acid rain, pollution from fertilizers and climate change (Pitt and Lucas 2014). It is worth noting that climate change is as a result of emission of greenhouse gases to the environment, carbon dioxide is one of the greenhouse gases that accumulate on the environment and water to create global warming that degenerates in climate change. Recent reports have confirmed that jellyfish numbers have been on the increase in the past years and it is a large trend that is expected to go on so long as ocean acidification will continue to be on the rise (Pitt and Lucas 2014).

Global warming as a result of human activities of deforestation and use of fossil fuels has resulted to heating ocean and sea waters. One factor that is known to encourage jelly fish production is presence of warmer waters; they are also able to tolerate interruptions in their reproductive strategies and stages and are thus complex and adaptable. Acidity has been responsible for abundance of jellyfish in the oceans because some species of the organisms clone themselves in such an extreme environment and others are able to reproduce sexually through polyp stage that ensures that large populations of immature jellyfish individuals are able to multiply as they wait for right conditions to mature to adulthood (Purcell et al 2010).

Ocean Acidification and Convenient Environment for Jellyfish

Acidic environment is known to be convenient for jellyfish and makes the species able to withstand an ecosystem that devastate other organisms, notably, infrastructure that human build like the pontoons, piers and even drilling platforms help provide anchors for jellyfish polyps, encouraging local population explosions (Rinkevich and Matranga 2009). It is believed that warmer temperatures as a result of global warming result in the expansion of other jellyfish populations into water that previously inhospitable (Rinkevich and Matranga 2009). For example, sea nettle Chrysaora Quinquecirrha is known to produce more eggs when temperatures are warmer because they appear tolerant to such high temperatures. Moreover, temperatures affect asexual reproduction of moon jellyfish and the fact that they persist longer with warmer waters, as the onset of cooler season signals, the signal of Medusae in many temperatures areas.

Nevertheless, studies have established that not all species thrive and flourish in warm acidic waters, cold specifies of jellyfish will appear to decrease in the situation that water becomes more acidic and warmer despite most of them expected to have upper temperature threshold (Rinkevich and Matranga 2009). Polyps are important for jellyfish, when water pH increases they tend to die and when the pH lowers they increase, likewise their mortality increase under continuous high temperatures and Medusae of the tropical declined dramatically in response to warmer temperatures in a marine ocean.



Experiments carried out in North Atlantic established that there is a relationship between abundance of jellyfish and pH, based on the finding it is supported that jelly fish tend to abundant in more acidic conditions (Gershwin and Earle 2013). Moreover, data currently available affirms that acidification is a major influence on jelly fish population especially in North Sea where jellyfish tend to thrive best when pH is reduced. Scientists have also established that little evidence is available to link between reduction of calcifying organisms to create ecological space and dominance of jellyfish (Gershwin and Earle 2013). Consequently, to support the assertion that jellyfish is abundant when pH is lowered, laboratory studies have opined that acidic conditions reduce formation of liths and shell in ocean organisms and this supports thriving of jellyfish and thus increasing their numbers (Gershwin and Earle 2013).



            Ocean acidification and abundance of jellyfish has been a topic of interest to many researchers. They have attempted to link lowering pH of ocean waters and abundance of jellyfish. Results have established that lowering pH increases numbers of jellyfish because they are able to tolerate such adverse environment unlike other ocean creatures. Notably, lowering pH promotes the growth of polyps which are fundamental in reproduction process to increase their numbers. Studies have revealed that when pH increases polyps tend to die and when it is lowered they flourish which is vital for continue growth of jellyfish numbers. To sum up, ocean acidification is disastrous to most marine organisms apart from jellyfish that is known to thrive in such adverse conditions, this has been the reason for the rise in numbers and hence abundance in major ocean waters. Jellyfish are also resistance to environmental stressor like lowering of pH since such conditions support their asexual reproduction.


Gershwin, L.A., 2016: Jellyfish-A natural history. Chicago: The University of Chicago Press, pp.


Gershwin, L. and Earle, S., 2013: Stung-On jellyfish blooms and the future of the ocean.

Chicago: The University of Chicago Press. pp. 18-27.


Murray, J. W., 2006: Ecology and applications of benthic foraminifera. Cambridge: Cambridge

University Press. pp. 107-123.


Pitt, K. and Lucas, C. H., 2014: Jellyfish blooms. Dordrecht: New York: Springer. pp. 55-63.


Purcell, J. E., Angel, D. L. & Aquatic Sciences Meeting, 2010: Jellyfish blooms: New problems

 and solutions. Dordrecht: Springer. pp. 77-81.


Rinkevich, B. and Matranga, V., 2009. Stem cells in marine organisms. Dordrecht: Springer. pp.


Tills, O., and Coauthors, 2016: Reduced pH affects pulsing behaviour and body size in ephyrae

of the moon jellyfish, Aurelia aurita. Journal of Experimental Marine Biology and Ecology, 480, 54-61