Choice, Control, and Training for Ectotherms
In this article, I’ll talk about how we can improve the lives of reptiles by thinking about what matters to them: giving them opportunity and motivation to perform natural behaviors, helping them feel safe around human caregivers, and reducing their stress by training them to cooperate in their own care.
Training behaviors and choosing reinforcers
At Reptelligence, we most frequently train husbandry behaviors that give animals more choice and control in their care. These include: targeting, stationing, shifting, entering and exiting crates, getting and staying on a scale, accepting a harness, and voluntary handling.
I also try to create environments and stimuli that encourage the practice of natural behavior. At The Living Desert, we also use these environments and stimuli in giving educational talks to visitors. It’s a win-win! The animals engage in natural behavior, doing natural locomotion movements and engaging in problem solving and making choices; learners can see the animals doing all these things, and it really helps build empathy and respect for an animal that might have previously been seen more as an object.
I also like to use a combination of the different training types to increase the enrichment density of the spaces that I have available to work with the animals. We don’t yet have as much data for reptiles as we have for mammals regarding the SEEKING system, time budgets and foraging patterns, but, through enrichment and training, I have found that reptiles do start to show some patterns. I’ve also found that when they are given opportunities to stretch out their foraging time through puzzles, environmental setup or training, it seems to result in a calmer and more tractable animal. I hope to study this more going forward.
Snakes are ectothermic: They rely on their environment to regulate their body temperature. If the environmental temperature does not suit their preferences or biological needs, heat or cold can become a high reinforcer—potentially the highest reinforcer. In extreme cases of cold, a snake may stop all behavior until they are warmed to a point that they are physically able to move. In a best-case arrangement of antecedents in a training environment, one would ensure the animal is at a comfortable temperature and is able to move through a gradient. It is possible to use this gradient and these choices as reinforcers in your training plan.
Snakes are both predator and prey. Adequate escape distance, and the ability to hide and choose when they feel safe to interact with an object or person, is of high importance for progressing an enrichment or training plan. As such, choice to engage and access to safe spaces hold some of the highest value as reinforcers.
Water, substrates, and novel objects and places are some other high-value reinforcers in my tool box. Water can have multiple presentations: We use a dripper, mist, simple variety in the dampness of the substrate, dishes, ponds and pools, and a “humidity box” (an enclosed container with a small opening, that has some type of warm, damp substrate inside—this encourages water into the air through evaporation but contains it in the box, allowing the animal to feel and breathe humid air). Substrates can include natural and non-natural materials like shredded wood and paper, leaves, soft blankets and towels—anything that allows for a different texture, different smells, and something different to explore. Novel objects and places can include: perching, shelving, plants, and things as simple as cardboard boxes and tubes.
You can, of course, also use food! There are challenges in being tied to this one reinforcer though, because often it is not the highest reinforcer you will have available.
I use all the above and more. Antecedent arrangement is hugely important. If I was going to speak in terms of dog training, I would say use those reinforcers that we generally term “functional rewards.” This is where your time studying natural history, and the individual reptile you want to train, really pay off. What would they most want, right now? That becomes your reinforcer.
Behavior modification for snakes
When addressing behaviors that are inappropriate or dangerous for the snake or their handlers, I use applied behavior analysis and positive reinforcement, always considering that the snake needs to feel safe so that learning can occur.
The important pieces for creating a behavior modification plan are: “What is the animal doing?” and “What is the function?” One important thing to keep in mind when thinking about modifying reptile behavior is that we frequently control 100% of the antecedents, as these animals live in enclosed environments. That’s not to say that the function is always readily evident or that the challenging or undesirable behavior hasn’t potentially become rehearsed behavior.
My strategy is first to take a very close look at the natural history of that snake. There are currently over 3,500 different identified species of snake. It is important to know the ecology and ethology of the one I am working with. Next, I record lots of data. How does the snake use their space? Do they use their space at all? What interactions result in relaxed behavior and curiosity? What interactions result in stress signals and escape-seeking or reactive behavior? What are the antecedents?
Once I have this information, I will look at ways to modify the environment and the antecedents such that I can start to build trust with that snake. This might look like changing the actual, physical habitat to allow for more flight distance, or introducing novel objects to encourage foraging and exploring behavior. I will frequently introduce simple food puzzles that allow the animal to start to make choices, do some problem solving, and go through more of their natural hunting behavior—this has added benefit if the snake is striking due to anticipating food. I may introduce options for more height, or more substrate, or more hides, that allow the animal multiple choices to move away and feel safe. If the habitat is small and there is no option to modify this, I may start to think about how I can expand space outside of the habitat to be safe and appropriate for training, so that the snake can have the flight distance that they need. This is all of course assuming I am starting with a healthy, well-fed animal. If this is not certain, a vet visit will be a high priority.
At this point I will begin to build trust with the snake. I will start to offer things that they like, and I will observe them, giving them the option of choice on how close they want to be. I will start by offering objects in the habitat with the doors closed and move to leaving the doors open. I will closely watch body language and start to allow the snake to say yes and no to things through their body language. I think this is a pivotal part, as most snakes do not get this option. Signs of stress are not always well interpreted or heeded in snakes. The snake has likely had to resort to more resource-draining behavior like striking, hissing, and posturing. When the caretaker shows that they can listen to these subtler signs, it builds trust and two-way communication. I tell caretakers to please remember that aggression is biologically expensive for all species, including reptiles.
Once the relationship is showing improvement and the snake is feeling safe, I will use various non-food reinforcers to start desensitizing and training incompatible behaviors, and behaviors that will allow the animal to practice natural exploratory behavior and motor patterns. I will continue to offer more choice and control, while I raise criteria and increase opportunities.
The importance of choice and control
As ectotherms, reptiles are amazing conservationists, with some—especially snakes—not moving if they can see no reason to move. I don’t think we know yet the long-term effect that this lack of physical movement and lack of carrying out normal behavior patterns may have on reptiles in human care, from a biological perspective over the course of multiple generations. Even snakes with an ambush predator hunting style, like the sidewinder rattlesnake have been found to travel over 1000 ft in a day, never returning to a home territory, with some snakes like the King Cobra recently found to traverse a home territory of over 25 square miles. These distances are massive compared to the amount of space and variety of stimuli that a snake will typically receive in human care.
In contrast to some snakes that may not move or do much in a deprived environment, some reptiles express stress and lack of stimulation in potentially self-destructive ways, developing hyperactivity, anorexia, stereotypies, or not thermoregulating properly. By introducing choice and control, by way of enrichment and positive reinforcement, we can reduce the stress that may be imposed by captive life, and thus reduce and eliminate these common behavior problems.
But perhaps the strongest motivator I can raise is an ethical one. If we know what these animals are capable of mentally and physically, is it appropriate not to offer choice and control? Is it appropriate to keep an animal in a potentially deprived environment? Snakes are one of the most misunderstood and persecuted of animals. When we provide opportunities for them to practice behavior and make choices, it not only improves that animal’s overall quality of life, it improves the relationship with the guardian or caretaker and more fully supports feeling empathy for that animal and that species.
Practical ways to increase choice and control
There are so many ways to increase the choices available to a reptile, to give them the motivation to perform more natural behaviors, and to give them more control over their environment. A good place to start is to thoroughly assess the habitat that is provided for the reptile. Are they able to use every part of it, from side to side and top to bottom? If not, what modifications can be made? Does the reptile utilize their entire thermal gradient? If not, why? Do the warm areas and cold areas, offer equaling appealing cover and shelter? Is it possible to offer more than one basking area or more than one cool area? What kinds of choices can I give for water? How can I give the animal an opportunity to go through an entire foraging and hunting sequence, potentially allowing them to make multiple choices over a longer duration? What novel objects can I introduce that may encourage exploratory behavior?
I use a lot of food puzzles and training, as well as access to new places to encourage exploration. Essentially, I’m training a shifting behavior, from habitat to exploratory/training area, or habitat to crate. Reinforcers for shifting can be food or non-food. After the activity, the snake can then shift back to the habitat. They can choose when they come out and when they go back. I can construct the environment and the stimuli so that the choice I’d prefer the animal to make is the most appealing and reinforcing to them.
When setting up an exploratory area, choosing what I will use is somewhat dependent on species. These can vary from exploring on the ground or floor to utilizing a perching or shelving device built for them, or a combination of the two. I also sometimes create sensory bins/tubs with different objects and substrates for the animal to explore. I use a lot of DIY food puzzles, modified canine and feline food puzzle toys, rodent tubes, and mazes. With a good setup, I can stretch out the hunting/foraging behavior sequence to a two- to three-hour activity, providing a great amount of physical and mental exercise, potentially in a very small space.
(This video shows a snake consuming a previously euthanized rodent)
A foraging maze
And, these techniques don’t just work for snakes! Target training tortoises, turtles, lizards and crocodilians is well-documented at this point. There are even some studies on reptile play and social behavior, an area of ethology that is lacking in research for reptiles in human care.
Enrichment tips for at-home reptile keepers
It’s possible to start small, really. Look at how your reptile uses the space they already have, and compare that to what you can learn about their natural history. Is there any change you can make that might encourage them to explore more and practice natural behavior? Is the animal a burrower? Can you provide substrate that encourages them to dig? Does the animal like to climb? Do you have perching and shelving and adequate cover that the animal feels safe to explore in this way? How are you feeding? Is it possible to stretch out the foraging time, by hiding food around the habitat, using some type of species-appropriate puzzle, or start a training plan? How do you allow your animal to say yes or no to human interaction or habitat changes? Spend time really looking at their behavior and preceding antecedents. If you’ve maxed out options inside the habitat, look at how you can use space outside of the habitat. Can you provide a safe area anywhere outside of the habitat to interact and or get exercise?
Simple puzzles for snakes can include cardboard boxes with all tape removed. Leave one side open or close it up and cut some holes large enough for the snake to get inside. For more advanced snakes, a lightweight bowl or plastic container turned upside down over a prey item can be a great next challenge. Always use objects much larger than the snake can swallow and observe how they interact with the object. Never use fleece, tissue paper or anything similar around the feeding area for snakes— they can swallow it accidently, by either mistaking it for food, or catching it up with the prey item when swallowing.
Body language is the best way to determine whether your efforts are providing a pleasurable experience for the snake. A visual reference to snake body language will be coming this year. For now, this page I made is a useful reference guide.
For tortoises, think about how you can slow down their feeding. Spread it out into smaller meals. Try hanging food to encourage them to stretch their neck muscles or placing meals into some type of holder on the ground that encourages them to rip and tear at food using their feet, rather than just picking it up and eating it.
Tortoises are a lot of fun to target train, and it can really enhance the human-animal bond. Try to break up line of sight in the habitat. Color or shape discrimination is another fun activity. If the tortoise can see everything from one spot, they will not be as motivated to walk to the other side. Also, consider offering different substrate options (deeper, damp, different textures), water wallows, jolly balls, holee roller balls, live plants, and places to dig. Another thing I really like to do with tortoises is offer more than one basking area. I find this really encourages them to walk around and use the whole space.
Water turtles and terrapins can be given simple food puzzles like a small frozen cube of pellets, insects, fish, and greens, or a floating dog toy ball with a hole in it. They can be recall, target, tactile, scale, and station trained. A guardian can provide floating platforms and basking options with some movement to them. One can introduce moving water or rain systems on a timer. Introducing basking platforms at different heights and made of different textures can allow the guardian or caretake to start to see the animal’s preferences. And, providing deep digging substrate close to the water source can help one see the full range of their natural behavior.
Lizard ecology is so varied, but a lot of the options listed above will work for them as well. I like to use perching with some movement to it. I often do crate training, particularly with smaller species that may be more frightened by hands coming toward them. There are some great bug-feeding devices that can be purchased or created that allow for slower release—again stretching out the foraging process and encouraging more duration in natural behavior patterns.
In summary, take a good look at the known natural history of the reptile, and then as a guardian, take data on the individual you have in front of you, and then slowly integrate changes, being sure to watch for signs of distress. Try to leave at least half of the habitat, if not 75% the same, each time you make a change, until you can adequately assess how the change is affecting your reptile. Both uncharacteristic lack of activity and hyperactivity can be signs of stress, as can escape-seeking behavior. All of the above are merely some ideas to get started; there is much more to be explored.
The one thing I’d like to be able to communicate to every reptile owner and keeper is that reptiles can learn; they have preferences, make decisions, and can be trained! Even if that isn’t enough to inspire all of us to start a training program, maybe there is some small change you can make as a pet guardian to give the animal under your care a little more choice and control in their life.
Carrie Kish is the director and co-founder of Reptelligence. She has been focusing on training and enrichment for reptiles since 2012, and has worked in animal care and training at The Living Desert Zoo and Gardens and The San Diego Zoo and Safari Park for a combined total of six and a half years. Before that, Carrie was a dog trainer for over a decade. While she still occasionally takes dog clients, she mainly focuses on research and training for reptiles, as well as running the Reptelligence Facebook page and the Reptile Enrichment and Training Facebook group.