January 11, 2013 Fish, Ocean Preservation No Comments

Fish are food for some, but is it really necessary to be removing millions of tons of them from the oceans each year in order to feed fish and other farmed animals? Wouldn’t it be great if there was something other than fishmeal that we could use that would benefit the fish and other animals just as much? Something that is more efficient, and less expensive? Research into soy, barley, and beer sludge is demonstrating that viable alternatives to fish meal are becoming available.

Soybeans could be used as an alternative to fishmeal; soy based fish meal and soybean oil could be an answer to declining fish meal production. Because of the decline of ocean fish used to make the product, fishmeal production is decreasing. So how could soy help solve this problem? It was found in a study that in a rainbow trout’s diet, soy protein concentrate can replace half of the fish meal without reducing performance. However, growth of the fish may be reduced if ¾ or more if the fish meal is replaced with soy protein due to low feed intake and low lipid digestibility. Finding other supplements to add to soy protein would be a plus.

Even better is barley. A protein has been developed that could be fed to trout and other commercially produced fish. There is a new enzymatic method that concentrates barley protein and produces raw material for ethanol; this process provides a high protein ingredient that has been shown to replace other, more expensive protein sources like fishmeal and soy protein concentrate in commercial fish feed. This barley protein concentrate has also been shown to meet the fishes’ protein requirements, and could eventually completely replace fishmeal in fish feed if other essential nutrients are provided as supplements. Using the barley protein could reduce the demand for the millions of tons of fish taken from the oceans each year.

Finally we have beer sludge: turning waste from breweries into food for farmed fish. Microbes are trained to eat food based waste water, then when dried the bacteria become high-protein flakes. By law, breweries and food makers must find safe removal solutions for waste water which can cost up to $3 million per year, however a company called Oberon FMR takes waste water off of companies’ hands for free and turns it into food flakes.

If these ideas can be further developed and eventually have goods brought into stores, we could be savings millions upon millions of fish in our oceans and finding efficient ways to use various lower-costing products in order to feed fish and farmed animals.

Did you know?

  • Fish supply the greatest percentage of the world’s protein consumed by humans. So why should we be using our fish supply on fishmeal if we can come up with other alternatives?
  • Most of the world’s major fisheries are being fished at levels above their maximum sustainable yield; some regions are severely overfished. Finding alternatives to fishmeal can help us preserve millions of tons of fish from our oceans!
  • The Grand Banks, a major fishing area for centuries in New England, are closed due to overfishing. We need to ensure this does not start happening to more regions.
  • Populations of commercially attractive large fish, such as tuna, cod, swordfish and marlin have declined by as much as 90% in the past century.
  • Each year, 70-75 million tons of fish are caught in the ocean; around 29 million tons is for human consumption. Using alternatives for fish meal would decrease the amount of fish needed per year drastically.
  • 15 out of 17 of the world’s largest fisheries are so heavily exploited that the reproduction can’t keep up, resulting in many fish populations decreasing rapidly.
  • Species of fish endangered by overfishing are: tuna, salmon, haddock, halibut, and cod.
  • In the 19th century, codfish weighing up to 200 pounds used to be caught. Today, a 40 pound cod is considered a giant. The reason for this is overfishing.
  • What do you think about soy, barley, and beer as alternatives to fishmeal? Have you heard of or can you think of any other ways to efficiently and effectively feed fish and other farmed animals?

Written by Aquaponics Team