Bull & BearBull markets are characterized by optimism, investor confidence and expectations that strong results will continue. It's difficult to predict consistently when the trends in the market will change. Part of the difficulty is that psychological effects and speculation may sometimes play a large role in the markets.
The use of "bull" and "bear" to describe markets comes from the way the animals attack their opponents. A bull thrusts its horns up into the air while a bear swipes its paws down. These actions are metaphors for the movement of a market. If the trend is up, it's a bull market. If the trend is down, it's a bear market.
http://www.investopedia.com/terms/b/bullmarket.aspFish isn't anything.
A whale is someone who buys large quantities of something, in this case Bitcoins.