In addition to pollution, any dolphins brave enough to traverse the Port River had to deal with boat strikes, infections, entanglement with nets and other marine trash and even deliberate attacks, In response, the Adelaide Dolphin Sanctuary was established by law in 2005, setting aside a small patch of river for the resident dolphin population (about 30 live in the river; another 300 visit the area regularly) and establishing resources for public education about the dolphins.