Using scent work as part of enrichment programs in shelters can improve both welfare and adoption rates for dogs
by Rachel Lane
You’ve probably heard people say that when you adopt a shelter dog, you adopt problems and bring home headaches—or another version of the same sentiment. I have heard this far too often, and it always makes me sad. Yes, it is true that sometimes dogs in shelters do display behaviors that adopters label as undesirable, but there are also lots of amazing animals waiting for their forever homes. Because shelters struggle with resources and are financially strained, many behaviors that adopters deem as undesirable are often caused by poor welfare and lack of enrichment.
Welfare Concerns for Dogs in Shelters
Poor welfare can result in behaviors such as anxiety, hypervigilance, apathy, fear, hyperreactivity, helplessness and a negative cognitive bias (Mellor et al., 2020). Conditions that can contribute to a poor welfare state include:
- Improper nutrition
- A physical environment that does not allow for species-typical behavior
- Lack of adequate rest
- Unpredictable events
- Acute or chronic injury or illness
- Lack of stimuli in the environment
- Aversive or absent interactions with humans or other dogs
One of the best ways to combat poor welfare in shelter dogs is to find activities they enjoy and that come naturally to them (Lopes et al., 2022; Herron et al., 2014; Wells, 2004a). Since a dog’s sense of smell is its most important sense (Wells, 2009), shelters should neither ignore nor overlook scent work enrichment activities. Scent work involves providing dogs with activities where they use their noses to find something hidden (Duranton & Horowitz, 2019).
There are two physiological benefits of scent work that help reduce a dog’s anxiety. First, dogs who spend time sniffing have lower pulse rates and greater heart rate variability than dogs who do not spend time sniffing (Amaya et al., 2020; At the Heart of the Walk, n.d.). This tells us that scent work impacts a dog’s parasympathetic nervous system in a way that helps them relax. Second, scent work activates a dog’s seeking system, which produces dopamine (Panksepp, 2010). The release of dopamine helps prevent anxiety and aversive conditioning (Zweifel et al., 2011). This means that if a dog is anxious before participating in scent work, scent work can help lower the dog’s anxiety. And, for less anxious dogs, scent work can help to ensure that their anxiety levels stay low.
Recent research found that dogs who participated in scent work had a more positive cognitive bias than dogs who were taught to heel (Duranton & Horowitz, 2019). When dogs have a more positive cognitive bias, they are more likely to have better welfare, which helps to reduce behaviors that many adopters deem undesirable.
Adopters select dogs for adoption based on their in-kennel behavior (Protopopova et al., 2014). Dogs who spend time at the front of their kennels, playfully interact with adopters and lie down beside adopters during meet and greets spend fewer days, on average, in shelters (Protopopova & Wynne, 2014; Weiss et al., 2012; Wells & Hepper, 1992). By contrast, the more undesirable behaviors dogs show, the less likely they are to be adopted, and longer shelter stays are likely to increase the chance that dogs will develop behaviors that make them less adoptable (Wells, 2004b). It’s a vicious cycle.
To discourage harmful ways of seeing and thinking about shelter dogs and address the real issues—improving the dogs’ welfare and providing enrichment—shelters should implement scent work on a consistent basis. Since scent work reduces behaviors associated with poor welfare in dogs and is an effective and cost-efficient enrichment opportunity, shelters can use it as a tool to help ensure that their dogs are adopted into forever homes.
Five Simple Scent Work Games
Scent work does not have to be complicated, time-consuming or expensive. It actually gives shelters the ability to provide more enrichment in less time. Scent work is simple enough that volunteers can carry out plans with the dogs, and it is easy enough that the majority of dogs can grasp it without needing any training. It can be as simple and inexpensive as utilizing the dog’s food and toys to create hide-and-seek activities. Creativity is the key, and the sky is the limit. Here are five scent work games to get you started:
Put treats inside toilet paper and paper towel tubes, fold in the ends of the tubes and then place the tubes into kennels. Staff can have a large tray of these ready to go (possibly prepared in bulk by volunteers) then give them to dogs throughout the day when the dogs are bored or as a part of the daily routine. For example, every day at 3:00 pm, staff hand out one of the treat-filled tubes as a snack.
Break the Box
Hide treats inside cardboard boxes. This activity can be done inside a kennel with one or two boxes or in a larger room (with one dog) with many boxes.
If dogs are removed from their kennels by staff for cleaning, the cleaning staff can hide treats for the dogs to find when they return. At first, the hiding places can be a little obvious. Then, when the dogs catch on, the hiding spots can be made more challenging. This might also provide the added bonus of making it easier to return dogs to their kennels.
At meal times for dogs who eat kibble, instead of feeding them out of a bowl, use scatter feeding.
Spread agility disc cones in a room and put a treat in the middle of each one. For a dog who has played this game several times, you could make it more challenging by leaving one or two cones empty. While agility disc cones aren’t items that shelters are likely to have lying around, they are relatively inexpensive and easy to find. A pack of 50 cones sells on Amazon.com for $6.
With a little bit of thought and creativity, any shelter can gather the materials for all of these scent work games. Saving cardboard tubes and boxes that the shelter already has on hand is a good starting point. Asking the public to donate these everyday household staples is another simple solution. Putting a basket in the bathroom with a sign instructing people to place empty toilet paper tubes in it is resourceful and gets the public involved.
Since meet and greets are more successful when shelter staff determine a dog’s preferred activities and share them with adopters (Protopopova et al., 2016), staff should monitor and record which activities different dogs seem to engage in the most. By knowing that scent work is a dog’s preferred activity, meet and greets can lead to more adoptions.
Pheromones and Aromatherapy
Research has found that dogs are able to perceive emotions through pheromones, meaning that dogs can smell stress (Kokocińska-Kusiak et al., 2021; Siniscalchi et al., 2011)! Dogs naturally avoid odors related to stressful and potentially dangerous situations (Kokocińska-Kusiak et al., 2021), but when they are unable to escape such odors, they become hypervigilant and over aroused. Since dogs new to a shelter are likely to be unsettled and stressed, the more measures that can be used to create a safe and relaxing environment, the better. Using scent work to reduce the stress levels of dogs in a shelter will reduce the stress pheromones present in the environment, and the reduction of stress odors inside the shelter will aid in reducing the stress incoming dogs experience.
Aromatherapy is an effective, paws-off practice that promotes in-kennel relaxation using pheromones and/or essential oils. Before introducing aromatherapy, shelters should research the essential oils selected because some are toxic to dogs and other animals. Also, it is critical to have a plan in place to ensure that the scents are switched out efficiently, dispersed equally throughout all kennels and replaced in a timely manner (Gunter & Feuerbacher, 2022).
Pheromones are body odors that communicate information to other individuals of the same species (Wyatt, 2014), even in the absence of the signaler (Siniscalchi et al., 2018). A common pheromone used with dogs is Adaptil®. It is a registered product and can be purchased as a spray, collar or diffuser. Dogs exposed to Adaptil® pant, stand and vocalize less, and spend more time sniffing the ground and lying down (Amaya et al., 2020).
Essential oils are strong scents extracted from plants (Bakkali et al., 2008). They often come in bottles with droppers and can be employed by placing a few drops onto a washcloth, piece of towel or blanket that is then placed into the kennel with the dog. Scents of coconut, vanilla, valerian, ginger, lavender and chamomile have all been found to promote relaxation in dogs (Amaya et al., 2020; Binks et al., 2018; Graham et al., 2005). Rosemary and peppermint scents promote movement in dogs (Graham et al., 2005), which might be good for dogs showing a lack of behavioral diversity.
Shelters that provide a relaxing scent to dogs should send a scented washcloth home with the dogs and their new adopters. Adopters should be instructed to place the washcloth on the dog’s bed, and to leave it with the dog when the dog is home alone. Herz (2005) found that smells can create a strong classically conditioned response. This means that if a scent helps a dog relax in a shelter, the scent will also help the dog relax at home. And dogs who lie on their beds and relax are less likely to display behaviors such as vocalization, hyperactivity and destruction—all behaviors commonly associated with adoption returns (Mondelli et al., 2004).
Scent Work Is for All Dogs
Scent work is appropriate for dogs of all ages (Amaya et al., 2020) and all breeds (Hall et al., 2015). Dogs who resource guard, suffer from an injury, have a tendency to consume nonfood items or are group housed may need special consideration; however, with a little creativity, these dogs, too, can benefit from scent work in lots of ways. Scent work is a valuable enrichment tool that improves the welfare of shelter dogs and helps them get adopted into forever homes. This cost-efficient and easy-to-implement activity (take a deep breath … incoming long sentence) promotes behavioral diversity, decreases the frequency of abnormal behavior, encourages species-typical behavior, increases dogs’ ability to manage challenges and promotes the positive use of the environment. Scent work works!
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