Editors' Summary: Humpback whales are endangered marine mammals, protected by the Marine Mammal Protection Act (MMPA) and the ESA. Hawai'i's seasonal thrill craft ban in humpback habitat provides additional protection. In 2004, a federal court ruled that the state's seasonal ban was preempted by the MMPA and the ESA. Below, Koalani Kaulukukui discusses the interplay of these two statutes, concluding that when a marine mammal is listed under the ESA, the more protective MMPA or ESA provision applies. Humpbacks must be given protections of the more stringent ESA, allowing Hawai'i to protect humpbacks to a greater extent than federal law.