Many shark species in the northwestern Atlantic have declined by more than half in just the last 8-15 years. In particular, the Great White shark has diminished by about 80% along the coasts of the United States and Canada. Declining shark numbers isn't just a problem for sharks; it's a problem for the oceans' environmental balance. You take away the shark, the top of the undersea food chain, and the effects are going to be disastrous for the rest of the oceans' food chain.
One problem may be long lining fishing. This fishing technique involves using thousands of hooks to catch tuna and swordfish. Sharks get caught by accident. It's estimated that 12 million sharks die each year as a result of fishing methods like this one.
This is why Sharkproject, an international organization of scientists, divers, and shark lovers whose aims are to research and protect sharks, exists. An important step to saving sharks is the dismantling of their negative image as bloodthirsty predators.