Research on sharks has been slow and inconsistent. There are two main reasons; one is the remoteness and inherent dangers and difficulties of studying sharks in their natural habitat, and two, the lack of funding. However, we are beginning to understand sharks and their behavior, where sharks go and why they go there. For example, satellite tagging of whale sharks has demonstrated that this species can be highly migratory traveling across ocean basins. Knowing that a species is highly migratory means it more susceptible to fisheries in areas where it is not protected. Acoustic tags have also been used to study sharks in a particular area to determine their residency status. Acoustic tags are attached to the sharks and receivers are placed on the sea floor so that when a shark with an acoustic tag gets close the receiver stores the data transmitted by the tag.