{"id":822,"date":"2021-08-26T09:47:27","date_gmt":"2021-08-26T09:47:27","guid":{"rendered":"https:\/\/www.science4wildlife.com\/?p=822"},"modified":"2021-08-26T09:49:48","modified_gmt":"2021-08-26T09:49:48","slug":"shifting-baselines","status":"publish","type":"post","link":"https:\/\/www.science4wildlife.com\/index.php\/2021\/08\/26\/shifting-baselines\/","title":{"rendered":"Humans transform the world, but they don\u2019t remember"},"content":{"rendered":"\n

In the last century, humans have so dramatically transformed the\nenvironment in which they live that the Earth has entered a new geological epoch:\nthe Anthropocene. The magnitude, extent, and rate of change in the environment\nis so great that it is often hard to comprehend.<\/p>\n\n\n\n

The difficulty people have to realize how much ecosystems have been transformed partly comes from an environmental generational amnesia 1<\/sup><\/em>, caused by shifting baselines<\/em> between generations 2<\/sup>:  children of each generation perceiving the environment into which they are born as normal, accepting new degraded states as the norm.<\/p>\n\n\n\n

Shifting\nbaselines have been associated with a wide range of global environmental issues\nfaced today, such as overfishing 3<\/sup>, defaunation 4<\/sup>, loss of natural habitats and processes 5<\/sup>, and increased levels of pollution 6<\/sup>.<\/p>\n\n\n\n

How have ecosystems changed over\nthe past century?<\/strong><\/p>\n\n\n\n

Quantifying\nchanges between baselines can be a difficult task as it relies on\nnot-always-objective human memory. Old photographs remain as witnesses of past\nsituations, showcasing drastic changes in the composition of ecosystems such as\nthe size and amount of fish that used to be taken out of the sea. <\/p>\n\n\n\n

There is evidence\nfrom shifting baselines occurring all over the world: studies show that in Eastern\nIndonesia, younger fishers perceived less the decline in the wildlife\npopulation, compared to older fishers  7<\/sup>. In the Bolivian Amazonia, younger generations perceived a lower\nnumber of locally-extinct tree and fish species compared to older generations 8<\/sup>. In Alaska, younger generations identified less overall change in\nclimate (e.g., increased temperatures, decreased snow cover)  than older ones 9<\/sup>. In Tanzania, younger fishermen were less likely to perceive that\nthe current size of the fish catch has declined and that fish stocks were\noverexploited, compared to older ones 10<\/sup>. Likewise in the UK, the older generation\u2019s perception about the\nabundance of ten local bird species overtime was more accurate than the younger\none, showing that younger, less experienced people were less aware of\nhistorical ecological conditions 11<\/sup>.<\/p>\n\n\n\n

The rate of\nchange between baselines of two succeeding generations is likely to have\nincreased in the past two centuries, following technological innovations\nleading to modified interactions with surrounding ecosystems, increased\nconsumption of goods, biodiversity loss, population growth, etc., to an extent\nthat baselines can now be drastically different for generations living at the\nsame time.<\/p>\n\n\n\n

Few places have\nlong enough biodiversity monitoring data to be able to measure the extent of\nchange, and a \u201crecent\u201d baseline from an older generation may not be\nrepresentative of historical reality. For instance, the number of salmons in\nthe Columbia River today is twice what it was in the 1930s. But at this time, salmon\nin the Columbia River represented only 10% of what they were in the 1880s 12<\/sup>. <\/p>\n\n\n\n

One needs to go\nto truly remote places to see what historical natural baselines could be like. In\nsome very remote islands in the Pacific where no human being ever lived, Pr. Nancy\nKnowlton describes coral reefs where 80% of the living biomass were top\npredators, an ecosystem structure never found in reefs where humans have been\nliving close by 13<\/sup>.<\/p>\n\n\n\n

Why does it matter? Consequences\nof shifting baselines<\/strong><\/p>\n\n\n\n

Shifting baselines lead to three major consequences 14<\/sup>:
(1) an increased societal tolerance for progressive environmental degradation, such as the decline in wildlife populations, loss of natural habitats, and increasing pollution;
(2) a change in people\u2019s expectations as to what is a desirable state (i.e., worth protecting) of the natural environment;
(3) inappropriate targets (i.e. based on what people know of a place at present) for environmental conservation, restoration, and management programs. For example, North Sea fisheries are managed using a baseline from 1970, but by 1970 there had been over a hundred years of mechanized fishing, which had been devastating for stocks 15<\/sup>.<\/p>\n\n\n\n

As Callum Roberts writes in The Unnatural History of the Sea<\/em><\/p>\n\n\n\n

\u201cShifting environmental baselines cause a collective societal amnesia in which gradual deterioration of the environment and depletion of wildlife populations pass almost unnoticed. Our expectations diminish with time, and with them goes our will to do something about the losses.\u201d
<\/em><\/p><\/blockquote>\n\n\n\n

How to limit shifting baselines?<\/strong><\/p>\n\n\n\n

Soga &\nGaston (2018) proposed four recommendations to prevent shifting baselines. <\/p>\n\n\n\n

  1. Restoring the natural environment, since environmental degradation is triggering shifting baselines in the first place. This could happen through rewilding and ecosystem restoration. Marine Protected Areas with fishing excluded have successfully demonstrated how ecosystems can recover to forgotten baselines, \u201crecreating the past people cannot conceive\u201d (Daniel Pauly)16<\/sup>. <\/li>
  2. Monitoring and collecting data, to allow future generations to have a solid objective baseline about past environments. The rise in citizen sciences is one approach to scale up data collection. Collecting data also enables the reconstruction of past environments to help present-day managers take decisions on what is a desirable state of the environment.<\/li>
  3. Reducing the extinction of experience by promoting people\u2019s interactions with natural environments.<\/li>
  4. Education, to reinforce people\u2019s familiarity with their environment and its past and current conditions. <\/li><\/ol>\n\n\n\n

    It may seem hard to understand how humans can deem normal an extensively exploited field in Europe or a defaunated forest in the Brazilian Atlantic forest. Part of the why probably lies in the fact that the currently living generations never experienced anything else, or their experiences may soon be forgotten.  Acknowledging the fact that what people consider a \u201chealthy\u201d environment is biased toward what they experience as being the natural world and that their experience is not complete, and objective, is the first step towards being able to see the bigger picture and limiting shifting baselines. <\/p>\n\n\n\n

    Daniel Pauly said that \u201chumans transform the world, but they don\u2019t remember\u201d. Now that we know we are forgetting, there is a chance to manage ecosystems in a better way, by learning from the past.<\/p>\n\n\n\n

    Photo credit:<\/strong> \u00a9Peat Bakke, flickr. <\/p>\n\n\n\n

    References<\/strong><\/p>\n\n\n\n

    \n

    1.           Hartig, T. & Kahn, P. H. Living\nin cities, naturally. Science<\/em> vol. 352 938\u2013940 (2016).<\/p>\n\n\n\n

    2.           Pauly, D. Anecdotes and the shifting\nbaseline syndrome of fisheries. Trends in Ecology & Evolution<\/em> vol.\n10 430 (1995).<\/p>\n\n\n\n

    3.\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 Ulman, A. & Pauly, D. Making history count: The shifting baselines of Turkish fisheries. Fish. Res.<\/em> 183, 74\u201379 (2016).<\/p>\n\n\n\n

    4.\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 Lotze, H. K. & Worm, B. Historical baselines for large marine animals. Trends in Ecology and Evolution<\/em> vol. 24 254\u2013262 (2009).<\/p>\n\n\n\n

    5.\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 Humphries, P. & Winemiller, K. Historical impacts on river fauna, shifting baselines, and challenges for restoration. Bioscience<\/em> 59, 673\u2013684 (2009).<\/p>\n\n\n\n

    6.\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 Lyytim\u00e4ki, J. Nature\u2019s nocturnal services: Light pollution as a non-recognised challenge for ecosystem services research and management. Ecosyst. Serv.<\/em> 3, (2013).<\/p>\n\n\n\n

    7.\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 Ainsworth, C. H., Pitcher, T. J. & Rotinsulu, C. Evidence of fishery depletions and shifting cognitive baselines in Eastern Indonesia. Biol. Conserv.<\/em> 141, 848\u2013859 (2008).<\/p>\n\n\n\n

    8.\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 Fern\u00e1ndez-Llamazares, \u00c1. et al.<\/em> Rapid ecosystem change challenges the adaptive capacity of local environmental knowledge. Glob. Environ. Chang.<\/em> 31, 272\u2013284 (2015).<\/p>\n\n\n\n

    9.\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 Herman-Mercer, N. M. et al.<\/em> Changing times, changing stories: generational differences in climate change perspectives from four remote indigenous communities in Subarctic Alaska. Ecol. Soc.<\/em> 21, art28 (2016).<\/p>\n\n\n\n

    10.\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 Katikiro, R. E. Perceptions on the shifting baseline among coastal fishers of Tanga, Northeast Tanzania. Ocean Coast. Manag.<\/em> 91, 23\u201331 (2014).<\/p>\n\n\n\n

    11.        Jones, L. P., Turvey, S. T., Massimino,\nD. & Papworth, S. K. Investigating the implications of shifting baseline\nsyndrome on conservation. People Nat.<\/em> 2<\/strong>, 1131\u20131144 (2020).<\/p>\n\n\n\n

    12.        Olson, R. Slow-motion disaster below the\nwaves. Los Angeles Times<\/em> (2002).<\/p>\n\n\n\n

    13.        Knowlton, N. What are shifting baselines\n. (2011).<\/p>\n\n\n\n

    14.\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 Soga, M. & Gaston, K. J. Shifting baseline syndrome: causes, consequences, and implications. Front. Ecol. Environ.<\/em> 16, 222\u2013230 (2018).<\/p>\n\n\n\n

    15.        Oceana. Daniel Pauly and George Monbiot\nin conversation about shifting baselines syndrome | Oceana.\n

    Daniel Pauly and George Monbiot in conversation about “shifting baselines syndrome”<\/a><\/blockquote>