We work with animals to teach cooperative behaviors so that they may voluntarily participate in their own care and become socialized family members. This means that they are choosing to interact with us and also means that they can choose not to. Welfare science informs us that providing control to animals is essential for them to experience good welfare and that control is made possible by offering choices. Offering animals choice and control over their actions and environment is considered among best practices in captive animal management.
We work with many species; however, a large part of our focus since 2017 has been on snakes. There are very few trainers and behaviorists focusing their attention on training, behavior, cognition, and welfare of snakes; our goal is to change that. The chart below contains possible behavioral indicators of a snake's level of relaxation, stress, and distress. It is to help recognize during interactions with them when the snake is saying yes/continue, or no/stop.
Resources: Zoo Animal Learning and Training (Wiley 2020), Reptelligence (Kish 2018), Mader's Reptile and Amphibian Medicine & Surgery (Elsevier 2019), Assessing reptile welfare using behavioural criteria (Clifford Warwick, Phillip Arena, Samantha Lindley, Mike Jessop and Catrina Steedman 2013).
This is a quick reference graphic: