Ecological relationships

Fish? I didn’t know anything about fish. I’m an expert in relationships.

This was Miguel Medialdea response when Dan Barber’s asked him how he became an expert in fish. Madiealdea is a biologist at Veta la Palma fish farm. The farm is remarkable: 27,000 acres of ponds and wetlands that produces 1,500 tonnes of sea bass, sea bream, sole and shrimp. What is truly remarkable, though, is that the farm is self-sustaining.

It’s such a rich system that the fish are eating what they’d be eating in the wild. The plant biomass, the phytoplankton, the zooplankton, it’s what feeds the fish. The system is so healthy, it’s totally self-renewing.

Veta la Palma is also an oasis for over 250 species of birds. The farm had previously been drained and used for cattle farming. During that time, the area saw the bird population decline by 90%. Now that the area has been reflooded, the birds have returned, including a flock of thousands of flamingos that flies over 150 miles to feed on the farm’s shrimp. When asked whether flamingos feeding on his shrimp wouldn’t damage his bottom line, Medialdea replied:

We farm extensively, not intensively. This is an ecological network. The flamingos eat the shrimp. The shrimp eat the phytoplankton. So the pinker the belly, the better the system.

Barber’s TED talk is a love song of sorts to the fish raised by Medialdea at Veta la Palma, and is well worth a watch.

I’m reminded again of the value of zooming out and considering the next larger context. Rather than focusing solely on the efficiency of the system—how many fish can we raise in a small space—Medialdea’s focus on the system itself results in something that is better than efficient.

But zooming out further makes me somewhat skeptical. When you consider the next larger context of Veta la Palma, it seems pretty unique, in terms of its location, its market and its approach to farming.

Not every wetlands is going to be well-suited to becoming a fish farm. And I suspect that not every wetlands should. Introducing new species of fish to an estuary wetlands is likely to have a huge impact. In the case of Veta la Palma, this was offset by the fact that the wetlands had been previously drained, so there was no aquatic ecosystem in place.

Veta la Palma also occupies an unique niche in the market. Dan Barber is, after all, a professional chef who is willing to pay for food he loves. Veta la Palma describes their sea bass as the pata negra of sea bass (after a premium Spanish ham made from Ibérico pigs), and I wondered if they charge a similar premium for their fish. While this seems to be true in the United States, where their sea bass sells for around $45 a fish. Aside from the fact that shipping fish to the US isn’t exactly sustainable, this doesn’t seem to be the case in Spain, where each lubina (aka “sea bass”) sells for around $3.50.

Finally, I wonder about how widely applicable extensive agriculture is. Dan Barber’s talk was the first time I’d heard of extensive agriculture, so I did what anyone would do: I looked it up on Wikipedia. According to the article, extensive agriculture is usually used in areas of low agricultural productivity. Yields are typically low for the amount of land used. While Barber largely presents extensive agriculture as a positive, I can’t help but wonder if it would feed the world sustainably if it were more widely applied. It’s a topic I need to look into further.

Don’t get me wrong, though. I think what Vata la Palma has done is extraordinary.

But I’m not sure if Vata la Palma is the model for all agriculture or even all aquaculture. I think they’ve come up with a unique solution for a unique situation.

In the end, I think that this is the point that Dan Barber is making, rather than holding up Vata la Palma as the best and only way to farm fish (though he does seem to propose extensive agriculture as part of the solution).

Miguel Medialdea puts it well:

Because of our artificial intervention, the natural environment is improved. The point isn’t to make use and conservation compatible. The point is to use in order to conserve.

So we’re unlikely to find a one-size-fits-all solution. It’s not that easy. Each solution is going to need to depend on the ecology of the area and the relationships of the species being farmed. And focusing on those relationships is the way to start finding those solutions.