Associated with the gills are structures called gill rakers. These gill rakers are dark and bristlelike and are used to catch plankton as water filters through the mouth and over the gills. The basking shark is usually grayish-brown in colour and often seems to have a mottled appearence. The teeth in the basking shark are very small and numerous and often number one hundred per row. The teeth themselves have a single conical cusp, are curved backwards and are the same on both the upper and lower jaws.
Basking sharks are a migrating species and are believed to overwinter in deep waters.
They may occur in either small schools or alone. Small schools in the Bay of Fundy have been seen swimming nose to tail in circles in what may be a form of mating behaviour. Diet Basking sharks are planktonic feeders. By swimming with their mouths wide open, they filter plankton out of the water with their long, tightly set gill rakers. The water then exits the body via the gill slits.