In general, the RSPCA is not opposed to the keeping of animals in government-endorsed zoos where zoos are able to meet the behavioural, social and physiological needs of their animals, have documented animal management plans, minimum enforceable husbandry standards, and devote resources to captive breeding of endangered species for release back into their natural habitat.
The problem with keeping elephants in zoos is that their needs cannot be adequately met in a captive zoo environment. Consequently, the welfare of elephants kept in zoos is severely compromised. Potential causes for poor welfare in zoo elephants include restricted space and opportunity for exercise, unsuitable climate, extended periods of confinement, hard or wet flooring, inappropriate diet, small social groups, lack of stability in social groups, lack of opportunity to exhibit natural behaviours, and exposure to aversive stimuli in training and handling. For example, zoos cannot provide adequate space for elephants. Elephants are, by nature, nomadic creatures that are constantly on the move. In the wild, an elephant will walk up to 9km each day. It is nearly impossible to provide, even an adequate amount of space and exercise, in a captive environment.
In addition, zoos cannot mimic the social structure that elephants need to thrive. Elephants in the wild can exist in herds numbering up to 58 animals. Female elephants particularly are intensely social animals, existing in small groups made up of mothers, calves, ‘aunts’ and so forth. These animals develop strong lifelong bonds with these family members. When elephants are held in captivity, moved and separated from their group, this cause unacceptable levels of distress and the breakdown of these family groups. A recent study showed that captive zoo elephants showed increased stereotypic behaviours such as weaving and pacing, where they were separated from other elephants or confined to indoor areas .
One argument put forward to justify the keeping of elephants in zoos is that they contribute to the conservation of the species. In fact, zoos have contributed little to the conservation of either African or Asian elephants since they were first brought into captivity. There is no evidence that captive breeding methods like artificial insemination have improved overall birth rates, as elephants in captivity have a high rate of stillbirths and a very high rate of infant mortality. Moreover, elephants in captivity die at a younger age, experience a range of health problems and also exhibit signs of severe stress, including the constant, repetitive ‘weaving’ that is familiar to many observers. Neither the World Wide Fund for Nature (WWF) nor the International Union for Conservation of Nature and Natural Resources (IUCN) think captive breeding contributes significantly to elephant conservation.
 Greco BL, Meehan CL, Heinsius JL & Mench JA (2017) Why pace? The influence of social, housing, management, life history and demographic characteristics on locomotor stereotypy in zoo elephants. Applied Animal Behaviour Science 194: 104-111.