We seem to be playing wack-a-mole when it comes to feedstock for farmed animals. In most of the world, livestock can graze for perhaps ¾ of the year. However, in countries with seasons, often in the winter the animals are in barns and are fed.
Often, this feeding fattens up the animal faster than grazing and so in many places is used all year round. However, from a nutrients point of view, this is highly inefficient and it’s far better for humans to simply eat the crop (the land needed to raise feed stock cattle could feed far more people if they simply ate the crop of food). In other places, this feed is made from meat.
In recent years, this foodstock has started to be made from fish, caught off the coast of south Africa.
This, however its not proving good for the local food chain. The majority of these fish are naturally eaten by African penguins, but with these being fished out, they are catching less fish, and having to swim further. As you can imagine, this is significantly affecting the penguin population, having significantly reduced the number of chicks that are raised significantly.
Without rapid action, we could see the eradication of many African penguin colonies. If the fishing continues long-term, it may well guarantee a slow decline to extinction. It is ironic as for many farmers, they switched to fish based feed, to avoid damaging places like the Amazon, which is otherwise cut down to grow the feed stock for cattle.