Are South Africa’s fisheries at the end of the line?
Colin Attwood
Zoology Department
University of Cape Town
Colin.attwood@uct.ac.za
Presented at a discussion of the film End of the Line, Applied Maths Building, UCT, 2nd
November 2010
1. The film follows from the book which was a well-researched and balanced piece
of work. It aimed to explain why fish stocks have collapsed. The film, as usual
never as comprehensive as the book, strives to make its points more powerfully,
but does so by being selective in its coverage of fisheries and using some
examples which have been discredited. I do not believe this diminishes the value
of the film. The film shocks its viewers and gets them angry and then offers
specific solutions such as MPAs, EAF, consumer awareness etc. In this respect I
put it in the same category as the End of Oil and the End of Suburbia. It is a useful
comment on humanity’s ecological footprint.
2. Criticise if you like, but we must appreciate what is involved in making a film.
THE FILM MUST MAKE MONEY. Do not expect DWG documents to attract
the attention of a film director. He needs disasters, flambouyant language, good
images and firebrands like Daniel Pauly. I can hear Barry Ronge raving about the
strong cast of the EotL, Daniel’s powerful performance, and the rise of the lowly
Worm. How else can we get messages to the public? Books don’t do it.
Newspaper features cannot cover all the ground. We need the film to get debate
going. And if this meeting is one of the products that followed from the film, then
I will say that it was a success in raising awareness on the mechanisms of overfishing, even if it got some of the details wrong.
3. What were the mechanisms of overfishing: Massive declines in fish abundance;
The effects of subsidies; Discarding; Ecosystem consequences; Exploitation of
the Africa; Sidelining of scientific advice.
4. To me the important question is whether and to what extent these mechanisms
apply to South African fisheries. In short, the answer is that our position is not as
pessimistic, but I would like to give an ecologist’s perspective in ten minutes. My
story is a tale of two fisheries.
5. Some species have been heavily impacted and remain at a very low level. The
clearest examples of over-fishing in SA are some of the linefish species. I recently
took the third year students to the traditional fishing port at Struisbaai. We have
some excellent records from the early part of the 19th C, including catch data and
commercial surveys. We looked at all the species caught by line and found that
three of these, 74, Red steenbras and Dageraad have declined to a very low level.
These two pies show how the species composition has altered. The reefs were
dominated by 74. Although the early data is open to some interpretation, whether
we look at CPUE or Spawner-biomass-per-recruit, the decline in these species
over the last 100 years is almost certainly greater than 90%. These were the long-
lived, sex reversing, predators that dominated the coastal reefs. They fetched a
good price, especially the 74. In many respects it is our equivalent story to the
rock-fishes of the Pacific, a massive species complex which has succumbed
heavily to fishing.
6. Why did these species collapse so quickly? Simple explanation – the number of
boats increased without restraint, gained access to the entire stock, before
government woke up. Ironically, in 1930, Von Bonde argued that our linefisheries
are primitive, and that they need to be replaced by new technology if this fishery
is ever to become a profitable business. He encouraged purse-seines, trawls and
trammel nets. 80 years on, we are still linefishing – for many species there is no
better method.
7. On the other hand we have a trawl fishery for sole, and whether by good fortune
or good management, we find that the catches of this species have remained stable
for almost 100 years. In the context on trawl fisheries internationally, let me tell
you that this is unusual. The more typical scenario is the boom-and-bust, and the
gradual rebuild. See north sea cod and Australian flathead.
8. Contrary to what might be understood from the film, it is not always the hightechnology industries and boardroom fishermen which decimate stocks. Nets that
can accommodate 12 Boing 747s, Boats with engines delivering over 1000 KW.
Longlines measuring over 100 km, and Mafia-controlled companies. These
images are contrasted against the artisinal fishermen, who make their own boats
and weave their baskets or the inter-tidal collector who uses her hands or simple
blades to ensure their daily survival. This kind of comparison is all a
smokescreen. The primary issue for sustainability is simply the amount of effort
applied in relation to the productivity of the fish populations. In SA our industrial
fisheries are relatively well-managed, our inshore fisheries are not.
9. Why are our industrial fisheries (sardine, south coast RL, hake, etc) well
managed, whereas the coastal populations are depleted? The answer is simply
economics. To manage a fishery, you need surveys and you need to count the
catch, then model the data and institute a system that encourages compliance.
These are costly exercises. And the cost is related to the geographical range of the
species, and not its abundance. i.e., it will cost as much to survey hake as it will to
survey red stumpnose. Linefish are valuable, in high demand, but their rarity
makes effective management difficult. My list of fish that are caught in all kinds
of gear tallies 507. About half of these are actually utilised. Of these, only 11 are
accorded the benefit of regular surveys and TAC limits. (hakex2, kingklip, monk,
sardine, anchovy, sole, swordfish, toothfish, tunax2). My theory is that we cannot
afford conventional management for any, but a select few of our species. My
question is how do we manage the rest?
10. This is basic model that you see in the text book. It tells us that if you don’t put
any effort into fishing, you catch nothing, but if you put in too much, you also
catch nothing, and cause extinction. The idea is to remain at MSY. This applies to
every fishery, be it recreational, artisanal or industrial-scale. The problem is that
species are not caught in isolation and that each species has its own production
characteristics. In the multi-species case, how do we approach the problem? Don’t
for a moment think that effort is set to match the productivity of the weakest
stock. We insist on the pot of gold, what happens to those species represented by
the curves on the bottom left? The smart ones in the audience will have answers,
e.g. MS ITQs, MS production models, closed areas. But what do we do about
these other species? Practically nothing.
11. This is a novel way of looking at fish species. Each circle represents a species.
The distance between any two species is a measure of the similarity of the
proportion in which it appears in the catches of all the different fisheries. So
species that are close together are caught by the same method, whereas those that
are far apart are caught by different methods. These circles indicate the sphere of
impact of each fishery. Prawn trawl, Purse-seine, Trawl, pelagic longline,
linefishing, estuarine fishing. Fish that lie towards the centre are caught in similar
proportions in two or more fisheries, and it is interesting to see that beach-seine
fishing occupies a central position, catching bits of everything.
12. When I highlight the quota-regulated species, note the clusters around them.
Shallow water hake, kingklip, sardine, anchovy, yellowfin tuna, in green are the
managed species. If your species is clustered around them, is that good or bad?
You might suffer as bycatch but you may also get surveyed in the process. What
about some other well known, but poorly managed species, in red, galjoen,
spotted grunter, harder, mini-kob. Vast areas of this spectrum are nowhere near a
properly regulated fishery.
13. We manage very few of the species that are impacted by fishing. If this is not
addressed, I fear that we could easily found ourselves in a situation as dire as
some of those described in the film.
14. We need to consider cheap and robust mechanisms to protect our incredible
diversity of fishes. I consider MPAs (or closed areas) to be in this category.
15. The small-scale fisheries policy is pushing co-management. It is backed by some
nice theory (reducing the commons, encouraging buy-in), but can we make it
work?