In Wyoming, all boats with any size motor, both gas and electric, need to be registered. Wyoming does not require registration of non-motorized watercraft, but be aware that some states do and you should check if you intend to use your non-motorized watercraft in another state. In addition, some national parks, including Yellowstone, require a permit to operate a non-motorized boat in the park. All watercraft using Wyoming waters are required to display an Aquatic Invasive Species decal. Non-motorized inflatable watercraft 10 feet or less in length are exempt.