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Exploring science at the British Library

3 posts from June 2015

30 June 2015

What's the catch?

On 23rd June the British Library hosted its 29th TalkScience event entitled ‘Fishing and marine protection: What’s the catch?’ For anyone who missed the event you can now watch the whole thing on YouTube. We have also summarised the highlights below. 

 

TalkScience is an informal discussion series focussing on topical issues in science. In the past we have covered issues such as climate change, GM foods and Open Data. During the event ‘Fishing and marine protection: What’s the catch?’ we sought to explore:

  • What are the impacts of fishing on the marine environment?
  • How do policies such as marine protected areas and fishing quotas affect sea-life and fishermen?
  • Must conservation and consumption always be at odds?
  • How will global environmental change affect our answers to these questions?

Guiding the discussion was marine biologist, author and broadcaster Dr. Helen Scales. Our panel of experts approached the topic from a range of backgrounds. Professor Callum Roberts is a marine conservation biologist at the University of York with expertise in marine reserves. Barrie Deas is chief executive of the National Federation of Fishermen’s Organisations, and was representing UK fishermen. Dr. Alasdair Harris is executive director of the social enterprise Blue Ventures, which aims to create sustainable tropical fisheries through local management.

Professor Roberts began by talking about the impacts of fishing on the ocean system and what we can learn from historical data. Mr. Deas then discussed some of the successes in waters around the UK and what marine protection strategies the fishing industry would favour. Dr. Harris finished by expanding the discussion to developing countries and the problems faced there.

Audience questions ranged from ‘Why is progress in marine policy so slow?’ to ‘As a consumer, what is the most important thing to think about when buying fish?’

TalkScience_23_6_15-03

We would like to extend a big thank you to everyone who turned up to help make the evening a success. If you would like more information about future TalkScience events, keep an eye on our TalkScience webpage, our Twitter feed @ScienceBL or the hashtag #BLTalkScience

 

16 June 2015

Fishing from the Earliest Times: A very brief history

Our next TalkScience event will explore the impacts of fishing on the marine realm. But how long have humankind been fishing for food? Peter Spooner delves into the British Library collections to find out.

Archaeology and Ancient Poems

Anatomically modern humans (Homo sapiens sapiens) have been eating seafood for at least 164,000 years. Caves in South Africa contain the very earliest evidence for humans eating shellfish, as well as evidence for humans eating shallow-water fish 140,000 years ago1. However, complex fishing equipment probably did not arise until much later. For example, the oldest known fishing hooks come from a cave in East Timor, South-East Asia, dating to 40,000 years BC2.

A Roman mosaic in shades of brown showing a variety of fish and cephalopods on a black background
Mosaic with fish, Pompeii, 1st Century B.C., http://commons.wikimedia.org/wiki/File:Mozaiek-uit-woonhuis-Pompei.jpg

By the time of the ancient Egyptians, and  then the Greeks and Romans, fishing with all kinds of equipment was common. Passages  in the works of Homer (8th century BC)3 and whole volumes by other scholars including Pliny the Elder (1st century AD)4, Ovid (1st century BC to AD) and Oppian (2nd century AD)5 describe fishing methods and the natural history of marine animals6. The latter works explain in incredible detail the habits and habitats of many animals, with examples including the migrations of tuna and the cleverness of dolphins.

These texts also provide interesting insights into the early development of some controversial fishing practices. For example, passages in Oppian’s ‘Halleutica’ and Pliny’s ‘Natural History’ describe early fish aggregation devices (FADs), which usually involve floating an object in the sea. Fish are attracted to the object and gather around it. They can then be easily captured. Today this is a method which risks causing overfishing7. Ancient versions of the FAD technique included hanging baskets in the water, or men venturing out day after day and feeding the fish by a particular rock until so many fish had gathered that it was easy to pull them into the boat. Another story in Oppian describes the use of a poison – derived from cyclamen root – to drive fish into waiting nets. Today, the use of poisons such as cyanide in fishing is described by the United Nations as a ‘destructive’ fishing technique8. But there are other ancient passages which refer to a much more wonderful kind of fishing.

Rear view of a dark-skinned man wearing a loincloth holding a large fishing net
Spiderweb fishing net from Pratt (1906)

Weird and Wonderful

One fishing method recorded by both Oppian and Pliny seems almost too remarkable to be true. It was written that in certain towns, fishermen would wade out into the water carrying nets or spears in readiness. Then they would shout and wait until dolphins came in from the sea, and the dolphins would drive schools of fish into the shallows where they could be caught. The men would reward the dolphins with fish and, according to Pliny, bread mash dipped in wine! This incredible practice still exists today in Brazil (though not, as far as I know, the wine), and fishing with the help of tame animals – such as otters and cormorants – still occurs in Asia9 (see reference for videos).

Amongst other almost magical fishing methods, people in New Guinea have used spiders to spin fairy-like fishing nets10. By setting a wooden frame in an area where spiders lived, they could entice the spiders into creating nets of just the right shape and size. Spider silk has also been used for centuries in kite fishing, where the silk lure is dangled below a kite at the surface of the water11.

A page from a medieval manuscript handwritten in Latin
First page of Ælfric's Colloquy, British Library

Medieval mismanagement

Compared to the ancient techniques  described above, modern industrial methods seem far more likely to result in unsustainable fishing. After all, how could a few hooks and nets pulled by hand or sailing boat catch enough fish to be a problem? Probably the earliest description of fishing in the English language is contained in the Colloquy of Ælfric12, a teaching manual for languages written in the late 10th or early 11th centuries. The description is in the form of a conversation between teacher and student, who is speaking in the role of a fisherman in England at the time. The teacher asks ‘Forhwi ne fixast þu on sæ?’: why don’t you fish at sea? The student replies lazily that it is too  far to row; he fishes in rivers instead13. But archaeologists have discovered that a major shift in English diet from freshwater fish to saltwater species was occurring almost as  this text was written. This shift has been linked to unsustainable management of freshwater systems, including the building of dams and the effects of farming on rivers14, and seems to be an early example of fishery expansion after local stocks collapsed. Given a few more years fishermen might have had to row the distance after all.

As illustrated by this example, sustainable fisheries management requires consideration of the whole ecosystem within which the fish live, as well as the needs of those who depend on the seas for their livelihood. Our next TalkScience event, ‘Fishing and marine protection: What’s the catch?’ will explore some of these issues. If you would like to be part of the discussion, tickets cost £5 and are available from our website.



1 C. W. Marean et al., 2007. Early human use of marine resources and pigment in South Africa during the Middle Pleistocene. Nature, 449, pp. 905-908, doi: 10.1038/nature06204. BL shelfmark: 6045.000000

2 S. O’Connor et al., 2011. Pelagic fishing at 42,000 years before the present and maritime skills of modern humans. Science, 334, pp. 1117-1121, doi: 10.1126/science.1207703. BL shelfmark: 8130.000000

3 For an example see: Homer, The Odyssey, Book XII lines 243-250. Translation by B. B. Powell. Oxford University Press, Oxford, 2014. BL shelfmark: General Reference Collection YC.2015.a.5169 

4 Pliny the Elder, Natural History / Introduction by Anthony T. Grafton, Translated by H. Rackham, [W.H.S. Jones and D.E. Eichholz]. Volume 2, Book IX. Folio Society, London, 2012. BL shelfmark: General Reference Collection YC.2012.b.985

5 Oppian, Colluthus, Tryphiodorus. With an English translation by A. W. Mair, pages 201-515. William Heinemann, London, 1928. BL shelfmark: General Reference Collection 2282.d.106. 

6 W. Radcliffe. Fishing from the earliest times. John Murray, London, 1921. BL shelfmark: Document Supply W18/7736

9 Videos of each of these practices can be found here. http://www.bbc.co.uk/nature/humanplanetexplorer/survival_skills/fishing#p009j8f5

10 A. E. Pratt. Two years among New Guinea cannibals: A naturalist’s sojourn among the aborigines of unexplored New Guinea. Seeley and Co. Limited, London, 1906. BL shelfmark: General Reference Collection 10492.g.15.

13 Ælfric’s Colloquy, edited by G. N. Garmonsway. Exeter Medieval English Texts, University of Exeter, 1978, pg 28. BL shelfmark: General Reference Collection X.908/42593

14 J. H. Barrett et al., 2004. The origins of intensive marine fishing in Medieval Europe: The English evidence. Proceedings of the Royal Society B, 271, pp. 2417-2421, doi: 10.1098/rspb.2004.2885. BL shelfmark: 6804.600000

08 June 2015

The Ocean: A sustainable future or the end of the line?

Peter Spooner dives into the issues of seafood sustainability in advance of our upcoming TalkScience event on 23rd June. Tickets are available from the box office.

The ocean is a vast place, covering some 70 % of the surface of the Earth. If Mount Everest sat at the bottom of the deepest ocean trench, two kilometres of water would still lie above it. It is baffling to try and imagine the numbers of creatures that survive and thrive in the swirling currents of the sea; and yet that is the task of scientists worldwide, trying to piece together scattered information to build a picture of the health of life in the ocean. But why has such research become so important?

Food for thought

Fish is an important source of protein, vitamin D and omega-3 fatty acids1. The government recommends that we eat at least two portions every week. A booming human population, growing appetites for fish and improvements in fishing technology mean that we now use at least 160 million tonnes of fish, shellfish and other marine life every year, mostly for food, and mostly taken wild from the ocean2.

Many scientists believe that such fishing pressure is not sustainable3. For the fish species where we have good data, populations have declined by 38 % since the 1970s4. Historical accounts of fish populations suggest that they have declined even more over the last century5. The fraction of global fish stocks fished at sustainable levels is also decreasing, with 30 % of fish populations now assessed as being overfished2. Wholesale species extinctions are currently rare in the ocean but local extinctions are increasingly common6. A famous example is that of the cod in the Northwest Atlantic, which were fished down to less than 10 % of their original stock over a period of about 30 years, and have not recovered7. Similarly massive reductions in populations have been recorded on a global scale for some fish including the Southern Bluefin Tuna8, and a quarter of all shark species are considered threatened9 (40 % in Europe10). Some fishing practices also cause extensive damage to the seafloor habitats that give many animals food and shelter. The accidental catching of species that are not the targets of fishing, such as turtles, is a major on-going problem.

Fishing and Marine protection

Image Credit: DJMattaar Thinkstock

Balancing the scales

Fishing and fish farming provide livelihoods for 10-12 % of the world’s population2. In order for fish and other marine life to continue providing an important source of protein, livelihoods in fishing and tourism, and benefits to the global environment, most agree that measures are needed in order to conserve fish stocks and to make them sustainable. In areas where action is being taken, such as the Northeast Atlantic, some species are showing signs of recovery2. However, there is disagreement about which strategies are the best. For example, marine protected areas are often favoured by conservationists due to their positive impacts on fish abundance, biodiversity and habitats11. When fully protected, they can offer an insight into what the ocean was like before fishing began. However, the creation of such areas may simply move fishing elsewhere and could take jobs away from local fishermen. In many parts of the world, enforcing protected areas without the support and help of local people is very difficult. Other controversial marine protection strategies are also hotly debated. For example, fishing quotas restrict landings of fish beyond specified levels, but often result in excess fish being discarded at sea.  How can we decide on the best strategies for ensuring sustainable seas? Should marine protection strategies be driven by governments or by those ‘on the ground’ (fishermen, local communities and consumers)? Does the best strategy change depending on where we are in the world? Is sustainability enough or should we be aiming to recreate the oceans of the past?

Seas of change

These questions become even more difficult to answer when we consider that the ocean and its ecosystems are in a state of continual change, driven by anthropogenic global warming, ocean acidification and nutrient pollution. Examples of the impacts of such changes include species moving poleward as the oceans warm, destruction of habitats including coral reefs, and the expansion of marine ‘dead zones’, where oxygen levels drop perilously low5. How might these changes affect the fishing industry? And how will our planning and implementation of marine protection strategies have to take these changes into account?

On the 23rd June the British Library will host our 29th TalkScience event: ‘Fishing and marine protection: What’s the catch?’ With the help of our audience, our panel of experts including Dr. Helen Scales, Professor Callum Roberts (University of York), Barrie Deas (NFFO) and Dr. Alasdair Harris (Blue Ventures) will attempt to answer some of the difficult questions posed here. If you would like to be part of the discussion, tickets (£5) can be booked via our website.

 


References with links to the articles and British Library holdings

[1] http://www.nhs.uk/livewell/superfoods/pages/is-oily-fish-a-superfood.aspx

[2] FAO, 2014. The State of World Fisheries and Aquaculture 2014 http://www.fao.org/3/a-i3720e/i3720e01.pdf

[3] D. Pauly, et al., 2002. Towards sustainability in world fisheries. Nature, 418, pp. 689-695, doi: 10.1038/nature01017, BL shelfmark: 6045.000000

[4] J. A. Hutchings, et al., 2010. Trends in the abundance of marine fishes. Can. J. Fish. Aquat. Sci. 67, pp. 1205–1210 doi: 10.1139/F10-081, BL shelfmark: 3031.490000

[5] C. Roberts, 2012. Ocean of Life: How are seas are changing. Allen Lane, Penguin Publishing. BL shelfmark: General Reference Collection YK.2013.a.1526

[6] D. J. McCauley, et al., 2015. Marine defaunation: Animal loss in the global ocean. Science, 347, pp. 1255641, doi: 10.1126/science.1255641

[7] R. A. Myers, et al., 1997. Why do fish stocks collapse? The example of cod in Atlantic Canada. Ecological Applications, 7, pp. 91-106, doi: 10.2307/2269409, BL shelfmark: 3648.855000

[9] N. K. Dulvy, 2014. Extinction risk and conservation of the world’s sharks and rays. ELIFE, 3, e00590, doi: 10.7554/eLife.00590

[10] IUCN, 2015. European red list of marine fishes. doi: 10.2779/082723

[11] S. E. Lester and B. S. Halpern, 2008. Biological responses in no-take reserves versus partially protected areas. Marine Ecology Progress Series, 367, pp. 49-56, doi: 10.3354/meps07599, BL shelfmark: 5373.904000