It's hard to imagine the damage over-fishing is wrecking on the oceans. The effects are literally invisible, hidden deep in the ocean. But there is data out there. And when you visualise it, the results are shocking.

This image shows the biomass of popularly-eaten fish in the North Atlantic Ocean in 1900 and in 2000. Popularly eaten fish include: bluefin tuna, cod, haddock, hake, halibut, herring, mackerel, pollock, salmon, sea trout, striped bass, sturgeon, turbot. Many of which are now vulnerable or endangered.

Dr Villy Christensen and his colleagues at the University Of British Columbia used ecosystem models, underwater terrain maps, fish catch records and statistical analysis to render the biomass of Atlantic fish at various points this century (see the study)

Memory vs forgetting

Researching this image, I read Professor Callum Roberts' harrowing book, The Unnatural History Of The Sea (Amazon US | UK). He uses historical accounts of the ocean to depict the sheer fecundity of the sea in the times before industrialised fishing.

These early accounts and data on the past abundance of fish help reveal the magnitude of today's fish stock declines which are otherwise abstract or invisible.

They also help counter the phenomenon of "shifting environment baselines". This is when each generation views the environment they remember from their youth as "natural" and normal. Today that means our fishing policies and environmental activism is geared to restoring the oceans to the state we remember they were. That's considered the environmental baseline.

The problem is, the sea was already heavily exploited when we were young.

So this is a kind of collective social amnesia that allows over-exploitation to creep up and increase decade-by-decade without anyone truly questioning it. Today's fishing quotas and policies for example are attempting to reset fish stocks to the levels of ten or twenty years ago. But as you can see from the visualization, we were already plenty screwed back then.

As Prof Roberts writes: "The greater part of the decline of many exploited populations happened before the birth of anyone living today."

See the visualisation at the top of the page. (I also made an animated GIF).

Information is Beautiful on vanishing fish stocks

It was created for European Fish Week which starts June 4th. It's highlighting the damaging results of decades of chronic over-fishing through exhibitions and events. Find out more and see more visualisations at http://ocean2012.eu/

Credits

Design: David McCandless

Map Render: Gregor Aisch

Source & Data: Hundred year decline of North Atlantic predatory fishes, V Christensen et al, 2003 - link (PDF)

Thanks to Pew Charitable Trusts.

About

I run InformationIsBeautiful.net, dedicated to visualising information, ideas, stories and data. Twitter @infobeautiful

My book of infographic exploria is called Information Is Beautiful. In the US, the book's called The Visual Miscellaneum

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