There have been great strides forward in aquafeed, but the industry will need to continue looking for even better solutions.
When I was first in the industry, feed was pelletised not extruded. It sank like a stone in the pens. The pellets were so hard that you couldn’t break them, though they still seemed to generate a lot of dust. It’s hardly surprising that FCRs [feed conversion ratios] were much poorer, as the fish had stomachs full of rock-like pellets.
There were so many things about feed then which were less than ideal. Mostly it was due to our industry having to use what was available rather than what was designed specifically for aquaculture. Oil levels reached an exciting high of 16% and I remember the first time it was suggested that oil levels could go above 20%. I was sure that the pellets would fall apart!
Part of the reason for the problem was that the feed mills were designed to produce feed for agriculture. This was a very price-driven industry; we tended to buy in relatively small lots and we needed the feed to last. Feeds were comparatively simple and low priced. People elsewhere in agriculture couldn’t believe the price of salmon feed, but then they hadn’t looked at the price of fishmeal and oil!
This was the centre of the problem. The mills were not designed to handle fish products of any quality and certainly not for digestibility or conversion potential. Furthermore, the fishmeals themselves were not of particularly good quality. So we had bad ingredients, a bad process and feed that was unsuitable for fish in almost every way.
As diets improved, salmon farming grew. Sometimes feed was too expensive but generally the development of high quality diets heralded profitability, driven by faster growth and better conversion. The industry’s efficient use of fishmeal also grew, but then the critics started to complain about its use. Efficiency of fish to fish conversion became a big discussion point despite the fact that the largest consumer of fishmeal was the chicken industry.
It became clear that the industry was going to use a lot of fishmeal and oil – albeit not all of it, because price and quality limited what was available to us, particularly on the oil side as the health capsule market – which used up the very best oils and was willing to pay a very high price to get them – developed. Meanwhile there was and still is a significant production of very low grade meals and oils. So the industry was pushed to looking at the use of vegetable oils and meals.
Here we arrive at the conundrum of how we feed our fish. Fish is the “natural” diet of salmon. If using vegetable material to feed our fish is more “sustainable”, this leaves us open to the argument: why not feed the plant-based food direct to humans?
Those people that hoped they could allay the concerns of critics by using vegetable matter in feed were in for a rude shock. The critics won’t go away because they make their living from having us to criticise. They are not passionate advocates of what’s best for the world, generally. I’m sure that the original starting point was trying to save the world, in the same way I got involved in farming, but somewhere along the line the whole process becomes corrupted. The point is that listening to them will rarely help a farming industry because that is not their aim.
Of course there are some wonderful methods by which we might feed our industry, such as conversion of food waste into worms or fly larvae; algae for oil and meal; or direct use of waste products from other food producers like chicken.
The problem is that those same critics would immediately use this attempt to reduce feed waste as these sources are unattractive to the consumer. Here lies another conundrum. We all know where a lot of the solutions lie but the very people who supposedly are trying to save the world make it impossible to use them.
As one very wise organic mussel farmer once said at a conference: “Where we are with criticism of aquaculture is like the first time a hunter brought two cattle into the village. ‘Why don’t we breed from these and then we won’t have to go out and die trying to get food’ the hunter said. Most of the village agreed but then there were those that said ‘Oh, but they will poop everywhere and kick the children’.” Oh and he didn’t say poop! But I hope you get the point.
There have always been those who know what everybody else is doing wrong. It’s important that this industry pushes on and finds new ways to grow more fish, using the best, most sustainable feed materials available.