Sardines
When most people think of sardines they are thinking of the little canned fish you find in the grocery store. However, this article will discuss the life of sardine fish before they end up as food. Although sardines are rarely kept in aquariums I thought it might be interesting for people to learn about how these fish live.
Sardines are small (approx 7-8 inches long) plankton eating fish. They live and breed in large groups. Because they are small plankton eating fish, sardines have low levels of mercury and are actually very healthy to eat. Fish lower on the food chain, such as sardines, don't have the high levels of mercury that are found in fish higher on the food chain, such as tuna. Sardines are also high in omega 3 fatty acids.
Little Fish in a Big Ocean
Being a sardine sure isn't easy. Being one of the smallest fish in the sea means that sardines have lots of predators. It isn't just people that like to eat sardines.
Because sardines basically have no defense against bigger fish, when threatened, sardines form into what is called a sardine ball. What happens is that the sardines pack themselves into the formation of a large ball. This means that at least some of them are protected from predation.
The You Tube video below shows a fish bait ball, when they are threatened by predators.
The Sardine Run
Many sardines live off the coast of Africa, until the ocean current carries its food source (the plankton) away. When this happens, the sardines must leave the relative safety of their current location and follow the plankton or they will starve. The sardines follow the plankton and then become susceptible to predation. This sardine migration is known as the sardine run. The last sardine run occured this past June/July 2013, but happens every year. It usually occurs sometime between May and August.
Watch the You Tube video below that shows predators going after a large school of sardines during the sardine run.
Notice how even the sea birds dive right into the water for a meal. These are fish eating birds called gannets.
Sardines are Important to the Ecosystem
As you could probably tell from the videos, sardines play an important role in the ocean ecosystem. They provide food for many different species.
I know that the next time I open up a can of sardines, it will be with newfound respect for these tiny fish.