Spatial considerations for captive snakes

Captive environments for snakes commonly involve small enclosures with dimensions that prevent occupants from adopting straight line body postures. In particular, the commercial, hobby, and pet sectors routinely utilize small vivaria and racking systems, although zoos and other facilities also commonly maintain at least some snakes under broadly similar conditions. Captive snakes may be the only vertebrates where management policy commonly involves deprivation of the ability and probable welfare need to freely extend the body to its natural full length. In this report, we present background information concerning some relevant physical and behavioral characteristics of snakes, discuss pervading beliefs or folklore husbandry and its implications for animal welfare as well as factors concerning stress, its manifestations and measurement, and provide criteria for the assessment of captive snake welfare. As part of this review, we also conducted an observational component involving captive snakes and report that during 60-minute observation periods of 65 snakes, 24 (37%) adopted rectilinear or near rectilinear postures (stationary 42%; mobile 37%). Of the 31 snake species observed, 14 (45%) adopted rectilinear or near rectilinear postures. Ectomorphological associations, normal behavior, and innate drive states infer that snakes, even so-called sedentary species, utilize significant space as part of their normal lifestyles. We conclude that future policies for snake husbandry require a paradigm shift away from an erroneous belief system and toward recognizing the greater spatial needs of these reptiles. (C) 2018 The Authors. Published by Elsevier Inc.