Fish hook with some form of corrosion-resistant surface coating. Corrosion resistance is required not only when hooks are used, especially in saltwater, but while they are stored. Additionally, coatings are applied to color and/or provide aesthetic value to the hook. At a minimum, hooks designed for freshwater use are coated with a clear lacquer, but hooks are also coated with gold, nickel, Teflon, tin and different colors. There are a large number of different types of fish hooks. At the macro level, there are bait hooks, fly hooks and lure hooks. Within these broad categories there are wide varieties of hook types
Fishing bait worms can grow up to 7 inches (18 cm) in length, but usually are between 3 and 4 inches (7–10 cm) long. Worm farmers also offer other worm species for bait, depending on availability, which usually depends on the prevalent climatic conditions. The capture, transportation and culture of bait fish can spread damaging organisms between ecosystems, endangering them. In 2007, several American states enacted regulations designed to slow the spread of fish diseases, including viral hemorrhagic septicemia, by bait fish. Because of the risk of transmitting "Myxobolus cerebralis" (whirling disease), trout and salmon should not be used as bait. Anglers