A lot of animal care professionals are writing about enrichment these days. It’s a hot topic.
One challenge we have as guardians of companion animals is how to think about how we enrich their day-to-day lives. What do we do outside of everyday care-taking routines to stimulate them physically and cognitively? Even professional animal caregivers get stuck in ruts on this one, which is unfortunate because well thought out enrichment provision can be one of the easiest strategies to foster behavior we like rather than behavior we find problematic. Appropriate enrichment is also an essential part of optimal animal welfare.
Whenever I visit animal care facilities of any sort, I notice what is or isn’t being provided as enrichment to keep my own ideas fresh. I ask questions about enrichment philosophies and routines. This summer I was thrilled to visit San Diego Zoo Safari Park. My niece and I took the behind-the-scenes Tiger and Friends Safari, which included a tour of the park with a knowledgeable guide as well as a tour of the behind-the-scenes area of the tiger enclosure. As is my wont, I gave our tour guide a heads up that I’d be asking a lot of questions about enrichment and training. He was up for it, having worked as a zoo keeper for years with the San Diego zoo and safari park as well as at the Sacramento Zoo, and having advanced degrees in animal-related sciences.
One of the goals of the San Diego safari park is reproduction of certain endangered species, including white rhinos. They’ve had a lot of success. More than 90 white rhino calves have been born there (http://institute.sandiegozoo.org/species/white-rhino). The safari park has also been instrumental in the recovery of the California Condor (https://en.wikipedia.org/wiki/San_Diego_Zoo_Safari_Park).
I expected some cutting edge stuff. When I asked about enrichment goals at the park, our guide said they use enrichment to keep animals occupied and mentally stimulated in order “to keep them out of trouble.” This is a simple goal. Let’s give them stuff to do to prevent problems. Not quite the advanced science I was hoping for (it was a public tour, after all), but all animal caretakers would do well to heed this basic rule of thumb. Give them things to do. Give them adequate mental stimulation.
How, specifically, do the folks at the safari park keep their charges mentally stimulated? According to my guide, they stimulate the animals’ senses: Provide them with different things to see, hear, touch, taste and smell. This is one way to structure an enrichment program for any animal. What can you do that is appropriate for a particular species and individual to stimulate its senses?
Let’s use dogs as our example here. Obviously, dogs’ primary sense is their sense of smell. Much of a dog’s brain is dedicated to processing scents (1), with up to 300 million olfactory receptors compared to our measly six million (2). That powerful sense needs plenty of stimulation. The simplest thing we can do is allow them lots of time to smell stuff on walks, which, of course, means walking them. When we can’t walk them adequately because of work or weather, we should provide extra stuff for dogs to investigate with their noses. Among the things I routinely provide to animals in my care are cardboard containers of one sort or another (toilet paper rolls, paper towel rolls, cardboard boxes) with some interesting scent and kibble or treats put inside them for the dog (or cat or horse) to work out. These are DIY food dispensing toys, but they pack an extra enrichment punch with the addition of scents. I vary the odors. Sometimes I use a drop or two of animal scents (rabbit, squirrel, duck, etc.) sold for training hunting dogs. Sometimes a sprinkle of extracts or spices from the kitchen. Sometimes a spritz of perfume. Frequently I distribute various tea boxes, which have the scent of the teas still in them. There are many other possibilities for olfactory enrichment, such as adding something like a teaspoon of broth or a sprinkle of parmesan cheese to regular meals. I’ve brought home hay and newly shorn wool from a friend’s farm for my dogs and cats to explore. Like so many other things, providing olfactory enrichment is limited only by your imagination (and safety, of course).
Vision is a secondary sense for dogs, serving in some ways as a backup to olfaction (3). Dogs see a narrower range of colors, but they see more detail, more movement, and better at night than we do (4). So, it is not silly to think about how to stimulate dogs’ sense of sight as well as smell. Allowing dogs to explore novel things they see in the environment, as long as they’re comfortable doing so, may help them to be more at ease with novel stimuli generally and is clearly cognitively enriching. In my walks with dogs, I often seek out novel visual stimuli such as statues or outdoor decorations for them approach at their pace, and feed them treats as they are doing so to associate the strange new objects with something positive. Even when we don’t see novel things on our walks, I provide my dogs with visual variation in their feeder toys. I use both red and black Kongs, and variously shaped slow feeders, for example. And, as I would with cats, I play with them with toys that they primarily locate and track with their sight to chase: balls, frizbees and flirt poles, which are like wand toys used with cats but for dogs.
Touch is often not thought much about with dogs beyond the puppy stage, when good socialization programs include having puppies walk on different surfaces and interact with objects that will feel different to them. Young puppies should walk on different surfaces (e.g., pavement, wood, carpet, sand, grass, turf, vinyl) so that they are comfortable with all they might encounter. But there is a lot we can do in relation to touch with adult dogs, too. We can vary the bedding they use so that they rest on different fabrics. We can use different types of grooming tools (soft brushes, rubber curries, metal slicker brushes, etc.) that feel different, as long as the dogs are comfortable with the tools used. We can set up ball pits for dogs to jump or poke a nose in, maybe in pursuit of some treats placed amidst the balls. We can let them explore water in kiddie pools or at the beach as they’re happy to do so. Having temperature gradients in possible resting areas stimulates dogs’ sense of touch; heating pads and cooling mats are easily obtained online. Like young children, dogs explore a lot with their mouths (5), so providing different chew items of various textures (bully sticks, bones, smooth and knobby nylabones, etc.) is another way to stimulate their sense of touch.
Hearing is an easy one, and a significant sense for dogs. Dogs’ sense of hearing includes sounds within our range of hearing and of much higher frequencies than we can detect (6). It is an excellent sense to stimulate. A fair amount of research indicates that dogs’ behavior is effected both positively and potentially negatively by different types of music (7), (8), (9). The gist of this research is that dogs appear to find some music soothing, particularly classical, reggae and soft rock, and that they will habituate to the same thing played over and over again. Further, dogs may find audiobooks to be calming as well (10). And, there is music acoustically designed to be soothing to dogs: “Through A Dog’s Ear” and related products. So, alternating playing types of music and audiobooks that may facilitate calm behavior is one way to provide enrichment to stimulate dogs’ sense of hearing as well as human-approved behavior at the same time.
The last sense, of course, is that of taste, and dogs possess the same taste receptors that we do: bitter, salty, sweet and sour (11). Obviously the sense of taste is stimulated by providing different types of food to eat. And, in dogs, because their sense of smell is so powerful, any change in food provides both olfactory as well as taste enrichment. It’s another enrichment double whammy.
Dogs and other companion animals who are busy using their senses in behaviorally appropriate ways are not getting into trouble doing things their humans don’t want them to do, at least while they’re engaged in those activities. And, if our pets use energy doing those things, they may be more restful and less hyperactive or destructive afterwards as well. Being attentive to enriching your pet’s senses daily is a win-win. It’s a habit that’s worth forming.
Disclaimer: Enrichment activities should be supervised to be sure they are safe for the individual involved. Individual animals may use an item differently than other individuals. Also, there may be new developments with regarding particular items that indicate they may be unsafe when they had previously been considered safe. Know your pets. If an item is likely to work well for one pet but not another, don’t provide it to the animal for whom it would not be appropriate.
(1) Horowitz, A. (2010). Inside of a dog: What dogs see, smell, and know. Simon and Schuster.
(3), (4), (5), (6)Horowitz, A. (2010).
(7) Kogan, L. R., Schoenfeld-Tacher, R., & Simon, A. A. (2012). Behavioral effects of auditory stimulation on kenneled dogs. Journal of Veterinary Behavior: Clinical Applications and Research, 7(5), 268-275.
(8) Wells, D. L., Graham, L., & Hepper, P. G. (2002). The influence of auditory stimulation on the behaviour of dogs housed in a rescue shelter. Animal Welfare, 11(4), 385-393.
(9) Bowman, A., Scottish, S. P. C. A., Dowell, F. J., & Evans, N. P. (2017). The effect of different genres of music on the stress levels of kennelled dogs. Physiology & behavior, 171, 207-215.
(10)Brayley, C., & Montrose, V. T. (2016). The effects of audiobooks on the behaviour of dogs at a rehoming kennels. Applied Animal Behaviour Science, 174, 111-115.
(11) Horowitz, A. (2010).