South Sioux City, Nebraska
South Sioux City defines a "dangerous animal" as:
"...any animal that is not naturally tamed or gentle, or that is of a naturally wild disposition, or that is capable of inflicting serious injury upon or killing human beings and having known tendencies, individually or as a species, to do so, or that because of its size or other characteristics would constitute a danger to human life or property if it is not kept or maintained in a safe manner or in secure quarters, including but not limited to the following animals, which shall be deemed to be dangerous per se: Bears, wolves, lions, tigers, panthers, bobcats, elephants, bison, poisonous snakes and spiders, alligators, crocodiles, anacondas, pythons, boa constrictors, and piranhas." [1]
And then such "dangerous animals" are prohibited with just a few exceptions that include almost no provisions for private ownership:
"...shall not apply to the keeping of a dangerous animal in the following circumstances:
(1) The keeping of dangerous animals in a public zoo, bona fide educational or medical institution, museum or other place where they are kept as live specimens for the public to view, or for the purpose of instruction or study.
(2) The keeping of dangerous animals for exhibition to the public by circus, carnival, exhibit, show or pet shop.
(3) The keeping of dangerous animals in a bona fide, licensed veterinary hospital for treatment." [2]
References:
[1] municode.com Code of Ordinances South Sioux City: Chapter 14, Section 14-1 Definitions
[2]municode.com Code of Ordinances South Sioux City: Chapter 14, Section 14-181 and 14-182 Keeping dangerous animals prohibited, and Exceptions