Critical Problems for Research in Animal Sheltering
Written by: Dr. Kevin Horecka
Edited by: Dr. Susan Amirian, Dr. Ellen Jefferson, Steve Porter, and Rory Adams
Animal Sheltering, in some form, has existed since the mid 1800s (with the creation of both the RSPCA and ASPCA in 1824 and 1866, respectively) and has been a constantly evolving field to both the benefit (Bornstein, 2015, Parlapiano, 2019) and determent (Roberts et al., 2012; see also this Maddie’s Fund’s 2019 talk for an overview), of its stakeholders: animals, pet owners, communities, and the organizations which tie these groups together. In the past several decades, a cultural shift has been occurring in which animal welfare (Hewson, 2003, Grandin, 2013) has received more attention, resources, and scrutiny than in the decades before. Many cities have been able to increase their live release rates and those of surrounding counties above 90 and even 95% (Neely, 2019), while smaller, rural shelters may be more likely to struggle due to limited resources. The space of problems in sheltering is enormous, and as awareness of the needs of shelters continues to rise, more and more groups — academic, corporate, non-profit, and private — are looking for ways to contribute to the wider movement of animal welfare using their unique skills and talents. One difficulty for these potential partners is in understanding what the needs of shelters are and what high-value unsolved problems exist in the field. Some of these are knowledge problems, others, implementation problems, and even more, systemic, cultural, and societal problems. Almost all require some manner of research to elucidate best practices and truths and differentiate them from traditions and myths. In order to aid interested parties in contributing to these areas of animal sheltering, this article seeks to enumerate and explain many of the critical problems for research in animal sheltering so that those organizations and interested parties might find a place to start to contribute. This list is not all-encompassing, but it covers 7 key areas (see Figure 1 for an overview), with examples, of critical problems for research in animal sheltering.
These key areas are:
Animal Behavior
Animal behavior is one of the most challenging and complex topics in animal sheltering. Leaving aside controversies surrounding the ethics of behavior adoptions, executions for behavioral issues, and the classic ‘nature v. nurture’ divide, the practical need to better understand animal behavior to improve the lives of animals and their owners has stood as Herculean task since its inception. Here, we highlight 4 key areas in animal behavior which may have the biggest impact in a shelter setting and for which we are sorely lacking an in depth understanding.
Although efforts to form a taxonomy of negative dog behaviors (see Behavior Problems of the Dog and Cat (Landsberg, Hunthausen, and Ackerman, 2011), recommended by the DACVB, for an overview of the topic — most easily available from a scribd free trial) and, specifically, dog behavior which may be adverse to a successful adoption and retention in a home (Patronek et al, 1996a, 1996b, Salman et al., 2000) have been attempted in the past (Beaver, 1983, Wright and Nesselrote, 1987; with interest in canine behavior in general rising sharply in the early 1990s; Figure 2) and more recently (Dowling-Guyer, Marder, and D’Arpino, 2011), no consensus has been reached upon a singular behavioral classification and identification system which can be used to make decisions around best practices with dogs with histories of behavior problems or potential for behavior problems. Such a classification system should have the following properties (see Patronek and Bradley 2016 (Patronek and Bradley, 2016) for a more detailed discussion of the difficulties surrounding some of these issues):
- Objective measurability and reproducibility
- Characterization of common temporal progressions
- Understood correlations between related behaviors
- Clinical relevance to predictability and intervention
Somewhat recent attempts (Mornement et al., 2010) at assessing the efficacy of behavioral evaluations have not been as promising as might be hoped given the 50+ year history of the field, and the impact of such a system, especially in establishing new interventions which can help these animals be successfully placed in homes, could be enormous given the extreme difficulty in achieving successful outcomes for dogs with behavior issues.
One key factor in negative animal behaviors, especially as pertaining to the adoptability of animals, is the stress they experience while in a shelter setting (Mccobb, et al. 2005, Gourkow, Nadine, and Fraser, 2006, Taylor et al. 2007). Studies of animal stress date back to 1926 (Cannon, 1926) with animals have often serving as a model for human stress (Patchev VK and Patchev AV, 2006, Campos et al., 2013). Biomarkers for stress(Nater, Skoluda, and Strahler, 2013) across species (Campbell et al., 1988, Contarteze, et al., 2008, Langgartner et al., 2018) have shown significant success in recent years, but the practical measurement of such biomarkers in shelter settings as a method of experimenting with environmental improvements is unlikely due to resource and practical constraints. Non-invasive measures of stress are possible in many species (including thermographic [Stewart et al., 2007, Cannas et al., 2018], salivary [Nemeth et al., 2016], visual [Hong et al., 2015], and multimodal [Alberdi, Aztiria, and Basarab, 2016] systems) , though their efficacy as an intervention target is unclear. A more thorough understanding of best practices around the reduction of stress for animals in shelters will allow for significant improvement in the quality of life of long-stay animals as well as the adoptability of animals which may show fewer behavioral issues once removed from a stressful environment (with some evidence showing changes in cortisol levels, a common biomarker for stress, with even a single night removed from the shelter environment in adult dogs; Gunter et al., 2019).
A key element in the success of an animal with behavioral issues, post-adoption is not simply the cessation of negative behaviors, but also the match with an adopter who is capable of maintaining the environment necessary for permanent improvement in behavior as well as following up with those adopters to ensure continued success is achieved. This problem comes down to two key sets of questions:
- How should shelters best match behavioral issues with potential adopters who can handle the maintenance surrounding those issues to reduce the chance of return and adverse incident (especially when evidence suggests choice of pet is often tied to factors like appearance more than behavioral considerations; Weiss et al., 2012)?
- What risks (i.e. environment impact on biting; Messam et al., 2008) exist in the home which might exacerbate issues surrounding behavior?
Finally, when it comes to animal behavior, especially canine behavior, one of the most critical incidents which can occur is a bite incident. The previously mentioned issues all likely contribute to the probability of a bite incident occurring, but predictions of such events, even in aggregate across a city (Zapata, 2016), are challenging at best. A successful bite prediction system would also pose ethical issues as individuals, shelters, and cities may choose to use such a system to decide which animals should be preemptively executed, to avoid the potential risk and liability. It is critical, therefore, that the predictability of bite incidents increase at the same rate as our ability to reasonably intervene to prevent the incidents.
Adoptions and Special Needs Populations
The core problem with adoptions at shelters is always “how do we get as many animals out to good homes as quickly as possible?”. Of course, as with so many seemingly simple problems, the posing of the question in such a general manner means no obvious solutions present themselves. Properly re-framing the question often begins to imply solutions. Here, we review 3 key areas in adoptions which remain complex and difficult despite extensive efforts in the sheltering community. For a more complete list of these challenge areas, see the American Pets Alive! Documentation on the topic.
First and most critically, large dogs (often considered to be those weighing over approximately 35 pounds or 16 kilograms) consistently have more difficulty in being adopted (DeLeeuw, 2008, Diesel, Pfeiffer, and Brodbelt, 2008, Protopopova, 2012). This can be due to factors such as the general public perception around larger breeds (Blecker, 2013, Gunter, 2016), city ordinances banning ownership of certain breeds (Nolen, 2017), housing restrictions implemented at the facility level (Graham, 2018), or concerns around safety, behavior, and compatibility with other home residents (Bir et al., 2016). These issues are exacerbated by the difficulty in accurately identifying breed information in shelter animal populations (Gunter, Barber, and Wynee, 2018). As a result of these complications around getting large breeds out of shelters, shelters often end up with a stagnant population of these animals which simply have less turnover than other, easier to adopt categories (puppies of any breed, for example). This can create a perception that the only populations present are these large breed animals. These factors result in many of these animals having long stays and, as mentioned in prior sections, increased stress and overall wellness difficulties which further worsen their adoptable potential. Moreover, animals in the shelter are less likely to behave the way they might otherwise in a home (Protopopova, 2016), further decreasing their chances for adoption. A strategy around breaking this cycle and helping large dogs would alleviate significant amounts of trapped resources as site maintenance and housing can create substantial costs and reduce flexibility in serving other populations.
Another, potentially less obvious problem in sheltering is the difference in societal interest in dog versus cat adoptions. This problem is not entirely understood, but it can be easily seen in examining Google Search frequency for dog vs. cat adoptions (see Figure 3). It is unclear what impact this disparity is having on outcomes for cats and kittens, but many shelters consistently report difficulties in adopting out adult cats once they no longer have the appearance of a kitten (Zito et al., 2015). Some strategies which are specifically applicable to cats have been evaluated and shown to be effective such as trap-neuter-return (Levy, Isaza, and Scott, 2014), but more research into the social drivers and potential interventions for this issue are warranted.
Beyond these major issues, there is a long tail of conditions which require increasingly complex adaptations of program and policy to accommodate. This article cannot enumerate all such conditions, but the following list (roughly in order of difficulty) captures some of the most critical special needs populations which require specially trained homes to inhabit (making them more difficult to adopt out):
- Geriatric Animals
- Animals with Chronic Allergies
- Hospice Animals
- FeLV Cats
- Kidney Failure Animals
- Diabetic Animals
- Behavior Animals
- Animals with Paralysis and/or Incontinence
Much of the care, maintenance, and treatment of these populations is fairly well understood, but the problem of placing them in amenable homes is still a significant one.
Finally, and not insignificantly, a more thorough understanding of how to match adopters to animals (Weiss et al., 2012, Curb, et al., 2013), how to evaluate homes for safety and longevity of adoption outcomes (Patronek et al. 1996a, 1996b, Salman, et al., 2000), how to optimize placement of animals in homes (O’Connor et al., 2017), and what preferences exist when it comes to adoption practices around marketing, visitation, and engagement is desperately needed. This understanding will likely depend significantly on local cultural distinctions in populations (Brown, 2002, Herzog, 2014) and is, therefore, difficult to examine systematically. More best practices around adoption matching and marketing would greatly simplify one of the most critical functions in animal shelters.
Medical Conditions
In addition to it’s capacity as an adoption agency for unowned animals, animal shelters often perform a variety of medical services. These services depend on the location, resources, and risk tolerance each organization has, and it is often difficult for organizations to decide what to treat and what to not treat (whether euthanasia is then called for or not). One critical element of this which remains a challenge for all shelters is the effective diagnosis of disease (see the April, 2012 article from Maddie’s Fund for an overview). Many diseases have fairly reliable tests (such as Canine Parvovirus) while others have a much more complicated history in the development of a reliable test (such as Canine Distemper, though many strongly claim RNA tests should be considered reliable; Frisk et al., 1999, Wilkes et al., 2014, Costa et al., 2019). Cost is also a critical factor in shelter tests as even a relatively inexpensive (50 dollar) test in an outbreak scenario can be entirely impractical in a population of just a few dozen animals. Further research into low-cost testing is certainly needed for a wide variety of diseases.
Once the disease is identified, shelters often lack the resources for what would be considered “standard” care in a private practice. Some shelters opt to not offer reduced care and, instead, euthanize, while others choose to offer whatever care they can within their own ethical limitations of suffering and quality of life considerations. The need for significantly more research into triage-optimized medical practices (see Figure 4 for an example for the Canine Parvovirus) around medical conditions seen in shelters is widely apparent. Some conditions, such as kitten diarrhea, may be somewhat understood in a general medical sense, but the treatments and time course do not scale appropriately for the model of a medium to large shelter.
Although many diseases could use additional scrutiny for the purposes outlined above, the following are of particular interest due to the costs (in either lives or resources) associated with typical treatment:
- Canine Parvovirus (Markovich et al., 2012)
- Feline Panleukemia (Truyen et al., 2009)
- Kitten Diarrhea (Strong et. al, 2019)
- Canine Distemper (Martella, Elia, and Buonavoglia, 2008)
- Fracture and Trauma Management
Disease Transmission
More so than the treatment of disease, the prevention of disease spread is one of the most challenging, concretely measurable (in the form of infection rates), yet ambiguous (difficult to diagnose in source) tasks a shelter may face. Shelters that treat infectious disease like the Canine Parvovirus establish quarantine areas in which only that disease is treated, but little is known about the ease with which these diseases spread under different quarantine practices (though practitioners will claim it is not being spread, it is difficult to accurately measure the spread given the inter-species communicability, unknown infectious dose, and unknown spread properties of most diseases in shelters).
Although there are many interesting diseases which are typically seen in shelters, the following are often seen as the most impactful/deadly and, therefore, would make excellent targets for more detailed studies of disease spread. They also, conveniently spread via somewhat different mechanisms:
- Canine Parvovirus (Markovich et al., 2012) and Feline Panleukemia (Truyen et al., 2009) — Fecal-Oral Spread, Difficult to Kill (Bleach is Usually Required), Long Lasting (1 Year+ on Surfaces), Transmitted through Particulate/Surfaces, Often Fatal but Treatable
- Canine Distemper (Martella, Elia, and Buonavoglia, 2008) — Airborne, Somewhat Difficult to Kill, Short Duration (Minutes in Air and Moisture), Transmitted through Water Vapor, Often Fatal even with Treatment
- Feline Leukemia Virus (FeLV; Little et al. 2011) — Bodily Fluids, Standard Disinfectant, Medium Short Duration (Hours in Fluids), Transmission though Fluids, Often Fatal after 1–4 years
- Feline immunodeficiency virus (Hosie et al., 2009, Huttman, 2011, Litster, 2014, Beczkowski et al., 2015) — Bites/Bodily Fluids, Easy to Kill, Does not Survive Outside Body, Precise Transmission Vector Poorly Understood/Controversial, Fatality Poorly Understood/Potentially Multi-Factor-Dependent
- Ringworm (Moriello 2014) — Contact Spread, Somewhat Difficult to Kill, Medium Duration (on Surfaces), Transmitted through Spores, Non-Fatal
When shelters experience outbreaks of these diseases, many will opt to kill their whole population rather than have it persist through many generations of animals flowing through the system. Better understanding of how to safely stem these outbreaks will allow shelters to more confidently avoid mass culling and take a more lifesaving approach.
Though canine-canine and feline-feline disease transmission is the most apparent form of transmission in shelters, it is thought that for many diseases, the source can be from wildlife rather than other domesticated animals (Fischer and Gerhold 2006). As challenging as studying disease spread is in a controlled environment of a shelter, it is even more so in wildlife populations, where movement is unrestricted and disease sources are largely unknown. Environmental surveys (Aguirre 2017) and computational epidemiological modeling (Krasnova et al., 2015; see Figure 5 for an example for Canine Distemper in shelters) can provide insights on spread, but they often fall short of providing interventions which might reduce intakes of animals acquiring the disease from wildlife. Future work may reveal more helpful preventative steps which could separate domestic and wild population transmission of some diseases or provide early warning signs/forecasting when a disease outbreak may be likely to occur.
Community and Wellness
Beyond the scope of the basic operations of a shelter in managing the conditions of individual animals and placing them in appropriate homes, shelters also serve a critical role in the community as providers of services which can enhance public perception and well-being (White, Jefferson, and Levy, 2010). This, of course, requires an engaged community. Best practices around establishing this engagement in an ever changing social landscape are difficult to come by, and smaller, rural shelters often do not have the resources to seek them out (see Figure 6 for an illustration of this issue). Increasing engagement can potentially have huge down-stream implications for shelters in receiving donated resources, volunteers, and in the handling of emergencies/disasters.
Another facet of community engagement involves understanding when and how animals end up in the shelter system in the first place so that preventative measure for animals entering shelters can be established (see Protopopova & Gunter 2017 for a review). Some communities have hotlines, spay and neuter programs, and other medical/behavioral services which can potentially contribute to this issue, but the efficacy of such systems and the gaps they leave are not well understood. More significant study of the needs of local populations as they relate to shelter success is needed.
Local populations also differ in their perception and support of shelter policies, ethics, and the local system of laws which are intertwined with these efforts. No unified system of ethics is established in animal sheltering, and communities often do not understand the nuances of practices in shelters (especially in regard to resource allocations and euthanasia practices). This makes galvanizing community support difficult, even in communities which have achieved very high live release rates. Public perception, messaging, and ethical alignment will undoubtedly continue to be an ever evolving socio-cultural landscape which is sorely in need of attention.
Lastly, and certainly not least, the mental health of volunteers, staff, and veterinarians (Jones-Fairnie et al. 2008) in animal shelters requires much more attention than it often receives. Individuals that participate in euthanasia are reported to have higher work stress and lower job satisfaction than their counterparts (Scotney, Mclaughlin and Keats, 2015). Suicide rates are significantly higher in the field of animal welfare than other high-stress fields (Tomasi et al., 2019, Fink-miller and Nestler, 2018), and more understanding and support is needing to help those working in these areas receive the help they need to continue to serve the community in a sustainable, healthy manner.
Operations
In addition to the study of animal-centric, adoption-centric, and community-centric aspects of sheltering, the study of the operations which contribute to the ability of shelters to continually adapt and advance is of critical importance if we are to have systems robust to disaster and capable of implementing our values and ethics on a global scale. Although blueprints do exist which can guide communities in setting up new shelters and enhancing existing shelters, significant problems still remain in the space beyond the distribution of known solution resources. Here, we discuss 4 key operations problem areas with varying levels of complexity:
Data Problems
Shelters need to collect data to know how they are serving their animals, adopters, volunteers, staff, and community, and how to improve operations in all areas of the shelter. The collection of this data often requires technical skills shelters do not have the resources to prioritize. Solutions such as ShelterLuv, Chameleon, and PetPoint for database management go a long way to improving situations for shelters, but the ability to flexibly collect and curate all manner of useful data remains an open problem.
Beyond this, shelters need methods of protecting themselves in the sharing of data with the public, academic institutions, and each other. The best practices around of performing data sharing and managing data access for shelters have yet to be established (though some progress has been made in recent months at the Municipal Shelter level; see Item 25).
KPI Problems
Once data is collected, linking that data down to trackable KPIs (Key Performance Indicators) which are useful to shelters in improving outcomes for animals is a challenge in and of itself. Shelters often point to Live Release Rate as a critical number, but with more innovative programs designed to prevent animals from ever entering the shelter system appearing, advancements in medical and behavioral interventions, and the geographically biased nature of animal population distributions (Rowan and Kartal, 2018), the use of a single KPI will likely remain a source of both conflict and difficulty for many shelters. A more diverse set of KPIs (see Figure 7 for an example of these KPIs) will allow for shelters to perform more nuanced comparisons of their successes and failures which will enable better sharing of solutions and resources. What this list of KPIs should entail remains an open problem.
Growth Problems
Finally, as some shelters begin to stabilize the animal welfare situation in their cities, adapting to the varying degrees and paces of growth in various organizations to ensure resources are being properly utilized to the benefit of animals and the community is a challenge, to say the least. The field of Health Economics in humans has a rich history (Jakovljevic and Ogura, 2016), and a similar field in Animal Health Economics will likely need to be expanded so that organizations are not put in a position to blindly guess at the proper allocations or resources towards different intervention programs (such as a Canine Parvovirus treatment program, FeLV treatment program, Behavior program, or Kitten Foster program).
One particularly challenging program area for shelters to understand in the context of growth, integration, and resource allocation is the management of Foster programs. Foster programs have been fantastically successful as a method of expanding the effective capacity of shelters, increasing live outcomes (Patronek & Crowe, 2018), enhancing community engagement, increasing quality of life of animals in care (Gunter et al., 2019), and providing special assistance for more difficult to adopt populations. However, a thorough understanding of how to best engage, utilize, and grow foster programs is lacking.
Public-Private-Academic-Corporate Collaboration
A less visible and virtually unstudied problem in animal sheltering is the ability for organizational entities of different types and with different incentives to collaborate to the benefit of animals, their owners, the community, and each other. Many questions in this space exist around the best ways for these organizations to interact (i.e. what roles are best served by what organizations, what incentives are best to ensure ethical treatment of all parties, and what restrictions should be put on various types of interactions).
Public-private partnerships in other areas of medicine have become increasingly common and valuable (Ballantyne and Stewart, 2019), and corporate sponsorship of shelters has become increasingly common. Public-private shelter partnerships are also on the rise with some proposing this structure as the new standard in the field (Kim, 2018). Academic collaboration with animal shelters, where academic institutions take advantage of the wealth of available subjects and data in shelters, is still a relatively new concept. Though many potential pitfalls exist in these collaborations (including issues with credit attribution, resource allocation, and ethical alignment), the potential to accelerate the state of the art in animal sheltering via these collaborations is huge thanks to the varied strengths of each organizational type (see Figure 8> for a schematic which illustrates hypothetical strengths and weaknesses of each organizational type).
What will this blog contain?
This blog is operated by American Pets Alive! (AmPA!) Research (see http://americanpetsalive.org/research for more information). As this is the first post from this blog, we would like to take a moment to tell you a bit about what we intend to post here going forward.
American Pets Alive! is an organization devoted to outreach and education around No Kill! practices which are meant to increase successful outcomes for animals in shelters and their adopters. AmPA! Research seeks to accomplish this goal by performing and collaborating in research around animal sheltering and its associated problems.
We currently have projects in most of the areas mentioned in this article, but many remain a nearly complete mystery. If you would like to help, see our website or email us at research@americanpetsalive.org.
This blog will contain the following types of content (typically noted at the top of the article):
- Field Reviews (such as this article)
- Literature Reviews (of specific or smaller topic areas of research)
- Research Reviews (of specific pieces of research)
- Original Research (performed by AmPA! Research)
- Program and Protocol Reviews (reviews of specific programs or protocols and their efficacy)
- Calls for Action (outlines of open problems for others to solve)
- Opinion Pieces (opinions of the researchers at AmPA! Research)
These articles will always be intended for a more technical audience, but summaries, condensed versions, and press releases can often be found in the main AmPA! website (americanpetsalive.org).
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