Fish: They Learn and They Remember

Are Fish More Capable Than We Make Them Out to Be?

Recently, an article by the national geographic was posted, titled Mystery Solved: Salmon Navigate Using Magnetic Field.
In this article, research explaining how salmon make their way 'home' to their original birth place in streams is explained. The sockeye salmon  is born in a stream, where they migrate to the ocean for years of their life, and return to the same stream where they were hatched to spawn again. They migrate over 2,000 miles to do this and until recently, scientists could never explain how.
They discovered fish have the ability to sense changes in the Earth's magnetic field. The salmon learn and remember the magnetic field that exists where they first entered the ocean. The key words here: Learn and remember.

This brought some questions to mind. How capable are fish of learning?
Throughout my life I had heard of fish only having a 3 second memory and couldn't learn anything. But is that really true?

I researched further and found an interesting journal article that discussed learning in fish.
The article can be accessed through this link. You will be redirected to a page and automatically asked if you want to download the file. Download it. : http://www.webcitation.org/query?url=http%3A%2F%2Fwww.geocities.com%2Fculumbrown%2FBrownLalandFAF2003.pdf&date=2009-10-25+17%3A58%3A51

More specifically, the article deals with social learning. In fish this is specifically learning by observation, by being around another knowledgeable animal, imitation, observing the consequences of a certain behavior, and learning from the presence or behavior of one individual that attracts another individual.
Research is presented that shows fish use these types of social learning in aspects of their survival such as "learning how to find food, which food to eat, to recognize predators, and assessing mate and rival quality" (p. 285). This research not only shows the capability of fish to learn, but also changes our perspective on fish and allows us to make changes that can benefit fish populations. It can solve problems such as the inability of hatchery-raised fish to identify predators and pick up on survival skills. Fish can be trained in mass to respond in certain ways that will allow for survival in the wild. This is a solution to a very big problem within the world of hatcheries, for over 90% of fish released from hatcheries do not survive past the first few weeks of being out in the wild. This is mostly due to starvation (they never learned how to find food or what food to eat) and predation (the never learned to recognize predators or to assess rival quality).
This information not only proved memory and learning in fish exists, but illustrated the extent to which it has affect on their survival. Without this memory and ability to learn, fish would be unable to survive.