Dr Bryony Caswell

Learning from past can help protect our oceans

From overfishing, to marine pollution and climate change our ocean resources are under threat. “Blue growth” agendas aim to develop ocean economies sustainably to benefit whole communities. However, a study says it is time for these agendas to learn lessons and heed stark warnings from the past.

Blue growth refers to the potential to grow marine or maritime economies in sustainable and equitable ways. These agendas are being led by the European Commission and the United Nations.

In the study, the researchers examined 20 historical examples of fisheries and aquaculture (fish farming), dating from 40 to 800 years ago. The study, led by the universities of Hull, Exeter and Boston, found consistent patterns that resulted in so-called “blue growth”. It also revealed common “recipes for failure” – and the authors say these offer grave warnings for today.

Dr Bryony Caswell of the School of Geography, Geology and the Environment at the University of Hull, said: “At this point in time – when the world has had a huge wake-up call – it is paramount that we start planning more effectively for the future.

“There are plenty of ways that we can build on the lessons from the past when it comes to managing fisheries and our use of other ocean resources, but we rarely use hindsight to support our decision-making.

“Even though mankind has faced comparable challenges in the past – such as major societal change (e.g., war, colonialism or regime change), technological revolutions, changes in labour or market demand, resource collapse and natural disasters – we are not very good at learning from them.”

Whilst some past societies ultimately failed at blue growth, others succeeded in balancing economic growth, social equity and sustainability for varying lengths of time. These are not yet guiding key sustainability strategies for our oceans today.

“Of course, the current situation is complicated by the challenges associated with the COVID-19 pandemic, and the UK’s impending departure from the EU’s common fisheries policy,” said Dr Caswell.

Dr Thurstan of the Centre for Ecology and Conservation at the University of Exeter’s Penryn Campus in Cornwall, said: “In basic terms, success came when societies managed to achieve fair – rather than unlimited or open – access to resources, and when they were responsive to change.

“Basing decisions on evidence, getting all parties involved and planning for the long-term were also key.

“Failure occurred when short-term gains were prioritised over long-term sustainability.”

Dr Caswell, said: “Worryingly, the recipes for success that we discovered are rarely included in even the most advanced blue growth agendas today.

“The seas are destined to play an ever-more vital role in food security. If we don’t take this chance to learn from history, we may be condemning ourselves to repeating past mistakes.”

The study, by an international team of 28 historians, environmental scientists and marine ecologists, looked at examples from around the world. These included:

  • In the east USA, two centuries of over-exploitation and worsening water quality led to a 20th Century collapse of once-widespread oyster reefs. While oyster production today is still far lower than historical levels, a growing appreciation of their benefits to coastal ecosystems has led to large-scale efforts by local communities to restore oyster reefs. Similar projects are currently underway in Hull.
  • Galway Bay, Ireland where, before the 1850s, community-based management led to equitable access and sustainable management of fish stocks. In the 1850s, trawlers from England arrived. Locally agreed rules were ignored and fish stocks were over-exploited.
  • In the Lagoon of Venice, Italy, local regulations achieved a “balance” between the economic freedom of citizens and the protection of shared resources, lasting from the 12th to the 18th After that, political instability and growing demand for food led to regulations being scrapped, resulting in over-exploitation.
  • In Sweden, lobsters were exploited more or less sustainably for 80 years before technological developments combined with inadequate management and monitoring led to over-exploitation.

Dr Emily Klein, of Boston University’s Frederick S. Pardee Center for the Study of the Longer-Range Future, said: “The question is, can our modern societies achieve blue growth rather than exploiting and depleting our oceans?”

“History shows us that there are ways to balance sustainability, social equity and economic growth.

“It is difficult, but we believe there are opportunities to make it happen – especially if we can learn from the past.”

The researchers also highlighted that the city of Hull itself would make for an interesting future case study: since it was founded upon a long and rich history of maritime trade and fishing since Viking times, and these industries were revolutionised many times over by technological innovations.

The paper, published in the journal Fish and Fisheries, is entitled: “Something old, something new: Historical perspectives provide lessons for blue growth agendas.”

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