The New Epoch

The Age of Man may soon be taking on an entirely new meaning as the geological epoch, the Anthropocene, awaits formal approval. The distinct geological periods and epochs of our planet’s 4.6 billion year history each signify specific events in earth’s past, but, humans have had such an impact on the environment that it is now time to leave our current epoch, the Holocene, behind. One habitat in which we know humans have had a significant influence is the marine environment, but, as this website will attempt to explain, what exactly are the consequences of this anthropogenic activity upon it, and to what exact will this affect life as we know it.

What is the Anthropocene?

The Anthropocene, a term originally coined by Crutzen and Stoermer (2000)1, refers to a new geological epoch which is dominated by intense human activity and was officially proposed by the Working Group on the Anthropocene (WGA) at the 35th International Geological Congress (2016)2. Despite arguments regarding it’s start date, some suggesting the mid-20th Century, it would represent a significant step in the history of human kind and the end of the Holocene which has lasted since the end of the last Ice Age around 11,700 years ago 2,3,4.

To be accepted by the international geology community there must be a clear distinction between the Anthropocene and the Holocene evident in the sedimentary rock strata and ice beneath our feet. These markers can take on many forms but may include radioactive material from nuclear activity, processed metals and alloys, plastics and or ‘black carbon’ resulting from incomplete combustion of fossil fuels. Additionally, alterations in the patterns of erosion or sedimentation due to construction activity, anthropogenic influenced fossilisation and or differences in carbon dioxide and ozone trapped in ice core samples may also be used as boundary markers 5,6. Even whilst we wait for official acceptance, the impact of humans upon the natural world should not be ignored and instead efforts should be made to ensure everyone is aware of the influence we are having 2.

Why are the oceans important?

The oceans are a vital ecosystem for a large proportion of the global population, especially coastal and developing communities. It provides a vital source of nutrition, and through commercial activity, can play an important role in income generation and economic viability. Around 3.1 billion people rely on fish for 20% of their per capita animal protein consumption, it accounts for around 17% of global animal protein intake (6.7% of ‘all’ protein consumed), and is especially important for developing and ‘low-income food deficit’ communities. A role that is likely to increase in relevance as the human population continues to grow 7,8. Oceans are also important for global system and ecosystem functioning. Photosynthesising phytoplankton are thought to produce around two-thirds of the earth’s atmospheric oxygen and therefore helps to underpin life for all terrestrial animals 9. Additionally the oceans may be playing a substantial role in inhibiting the negative temperature raising effects of increasing atmospheric greenhouse gases as they have absorbed about 40% of all anthropogenically emitted carbon dioxide from the start of the industrial revolution 10. It’s clear that the oceans are a vital component for the functioning of our planet and effort should be made to understand the potential damage humans are inflicting on it in order to hopefully prevent further consequences.

Make sure to check back here at marine-anthropocene.com for opinion pieces and research summaries regarding marine conservation and other topics associated with human impacts on the marine environment.   

Source information

  1. Crutzen P.J, Stoermer E.F. (2000). The “Anthropocene”.  Global Change Newsletter 41http://mfkp.org/INRMM/article/13558644
  2. Working group on the Anthropocene. What is the ‘Anthropocene’? – current definition and status. https://quaternary.stratigraphy.org/workinggroups/anthropocene/ [Date accessed: 22/08/2017]
  3. International Commission on Stratigraphy. International Chronostratigraphic Chart. http://www.stratigraphy.org/index.php/ics-chart-timescale [Date accessed: 22/08/2017]
  4. International Commission on Stratigraphy. GSSP Table – All Periods. http://www.stratigraphy.org/GSSP/index.html [Date accessed: 22/08/2017]
  5. Waters C.N. et al. (2016). The Anthropocene is functionally and stratigraphically distinct from the Holocene. Science 351 6269 http://science.sciencemag.org/content/351/6269/aad2622
  6. Jablonski D., Shubin N.H. (2015). The future of the fossil record: Paleontology in the 21st century. PNAS 112 16 http://www.pnas.org/content/112/16/4852.full
  7. Worldometers.info (2017). Worldometer. Dover, Delaware, USA. http://www.worldometers.info/
  8. FAO (2016).The State of World Fisheries and Aquaculture 2016. Contributing to food security and nutrition for all. Rome. 200 pp. http://www.fao.org/3/a-i5555e.pdf
  9. University of Leicester (2015). “Failing phytoplankton, failing oxygen: Global warming disaster could suffocate life on planet Earth.” ScienceDaily. https://www.sciencedaily.com/releases/2015/12/151201094120.htm
  10. Fletcher S.E.M. (2017). Climate science: Ocean circulation drove increase in CO2 uptake. Nature 542 169–170 doi:10.1038/542169a

Noise Pollution and Bluestreak Cleaner Wrasse

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Two Bluestreak Cleaner Wrasse (Labroides dimidiatus)  cleaning the mouth of a patient Giant Moray Ell (Gymnothorax javanicus). Photograph by James A. Dawson

 

From the whirr and hum of ship propellers to the deafening booms of military and construction activity, the oceans are awash with noise. Often overlooked, this pollution may be having a far more detrimental effect on marine wildlife than once thought. An issue that has been recently demonstrated by a study investigating its influence on the behaviour of cleaner fish.

 

 

Nedelec et al. (2017) has shown that noise created by passing motorboats may disrupt the fascinating interaction between Bluestreak Cleaner Wrasse (Labroides dimidiatus) and their clientele, other fish of the reef. These cleaner wrasse remove ectoparasites from fish who visit their cleaning stations and is a vital process for the health of individual fish as well as the biodiversity of the reef 2. Under the influence of passing motorboats however, the authors demonstrated that Bluestreak Cleaner Wrasse spent longer cleaning clients and were also more likely to ‘cheat’ by feeding on the mucous instead of ectoparasites. This cheeky behaviour is usually punished by clientele, often through chasing, however under these noisy conditions this cheating is punished less often. A consequence that the authors speculate may result from cleaner wrasse taking advantage of distracted clientele 1.  Though the direct influence of this noise pollution on parasite behaviour and actual parasite removal rate was not investigated, this is a worrying pattern given the importance of these cleaning interactions for reef ecosystems 2. Maybe future research should focus additionally on the influence of louder noises, different sources of noise pollution, and its long-term effects, to truly the predict the potential consequence of future marine based human activity.

Source information

  1. Nedelec SL, Mills SC, Radford AN, Beldade R, Simpson SD, Nedelec B, Côté IM. Motorboat noise disrupts co-operative interspecific interactions. Scientific Reports 7, Article number: 6987(2017). doi:10.1038/s41598-017-06515-2
  2. Waldie PA, Blomberg SP, Cheney KL, Goldizen AW, Grutter AS. Long-Term Effects of the Cleaner Fish Labroides dimidiatus on Coral Reef Fish Communities. Liu DX, ed. PLoS ONE. 2011;6(6):e21201. doi:10.1371/journal.pone.0021201.