Animal hoarding is a mental health disorder marked by a pervasive and persistent need to accumulate inappropriate numbers of animals, according to the Mayo Clinic. The behavior is accompanied by an inability to part with these animals. Cleaning up an animal hoarder’s house can be a daunting and dangerous task.

There is no clear data on how many animals in California or the United States are subject to hoarding. The American Society for the Prevention of Cruelty to Animals estimates that approximately 250,000 animals are the victims of hoarding at any time in the United States.

There are a number of key issues associated with addressing a situation involving an animal hoarder. Chief among them is how to clean up an animal hoarder’s house. In order to understand what is necessary to clean an animal hoarder’s home, a person must understand some of the fundamental elements associated with this type of hoarding.

Animal Hoarding Specifics

At the present time, animal hoarding is considered to be a subtype of hoarding. There are experts in the field who argue that pet hoarding needs to be set aside as a specifically classified mental health disorder in its own right.

The ASPCA explains that animal hoarding is a complicated matter that requires a close examination of:

  • Mental health issues for the hoarder
  • Animal welfare issues
  • Public safety concerns

Animals Commonly Hoarded in California and the United

Any type of animal can be hoarded. Of all animals hoarded in the United State, cats are the most frequently subject to hoarding. Other animals that are the most frequently hoarded in the United States include:

  • Dogs
  • Rodents
  • Reptiles
  • Birds

Animals typically associated with farms are also hoarded with some regularity in the United States. These animals include:

  • Chickens
  • Cows
  • Pigs

Primary Reasons Why People Hoard Animals

People hoard pets for a variety of different reasons. Research is ongoing, and in somewhat of a preliminary stage, when it comes to why people hoard animals. In many cases, a person who has a history of hoarding items eventually becomes an animal hoarder. There are situations in which the first “thing” a person hoard is animals.

With that said, experts in the field have identified some common underlying reasons that give rise to animal hoarding:

  • Attachment disorders
  • Personality disorders
  • Combination of attachment and personality disorders
  • Paranoia
  • Delusional thinking
  • Depression
  • Anxiety
  • Other mental illnesses

Criteria Utilized to Diagnose Animal Hoarding

Before assistance can be extended to an animal hoarder, including animal hoarder cleanup, a person needs to have an appreciation of the criteria used to identify animal hoarding in the first instance. These criteria include:

  • A person possesses more than the typical number of animals
  • A person is unable to provide even a minimal standard of care for these animals
  • An individual cannot meet the minimum standards of nutrition, sanitation, and shelter for the animals
  • The animals do not receive appropriate veterinary care
  • An individual denies his or her inability to provide even minimal care for the animals
  • A person is unable to recognize the negative impact on the animals of the excessive accumulation of them

Signs of Animal Hoarding

There are a number of signs of animal hoarding:

  • Numerous animals at a residence, but the suspected hoarder has no idea how many
  • The residence itself is deteriorating, including broken furniture and windows as well as extreme clutter
  • A strong smell of ammonia at the residence
  • Floors may be littered with dried urine, feces, and vomit
  • Animals at the residence are not well socialized and appear emaciated as well as lethargic
  • Fleas and vermin are present at the residence
  • The suspected hoarder is isolated from others
  • The suspected hoarder appears to neglect his or her self
  • The suspected hoarder insists that the animals are healthy and happy, even though the animals are in evident distress and are unwell

The Hidden World of an Animal Hoarder

Many people live in a hidden hoarding world of their own. This includes people who hoard animals, at least initially. 

A majority of animal hoarders are fairly well adept at concealing what is going on within their homes from other individuals, including their own family members who do not reside with them. Eventually, as conditions at the residence decay, and an unusual number of animals are seen outside the home, hiding animal hoarding can become a significant challenge.

Animal hoarders keep others out of their homes. They make up a myriad of excuses for keeping people out of their homes. These excuses prove convincing and believable. Some animal hoarders carry on normal activities of daily living away from their residences.

Actions to Help Animal Hoarder

Getting an animal hoarder to accept help can be highly challenging. The first step is to reach out to the animal hoarder. The objective is to establish a relationship of trust with the animal hoarder. A pet hoarder needs to be convinced that his or her animals are in need of immediate assistance, that the lives of these animals are in immediate danger.

Once movement is made in this direction, the next step is to receive assistance to clean an animal hoarder’s house. The assistance of a compassionate, experienced, well-trained animal hoarding cleanup specialist is required. As will be discussed in a moment, this is a professional trained in what technically is known as biohazard remediation.

Primary Consideration of Animal Hoarding Cleanup

Animal hoarding presents a number of concerns that must be taken into consideration during the cleanup or remediation process:

  • Safety and welfare of hoarder
  • Animal welfare
  • Public safety

In addition to these considerations, when an animal hoarding situation needs to remediate, there will be biohazardous materials at the premises, according to the University of California. This includes animal urine, feces, and other bodily fluids. It will also include the remains of dead animals, in most cases.

Because of the safety issues, and the overall challenges of cleaning up a hoarder’s house, you need to give serious consideration to retaining the services of a professional biohazard remediation service. This type of specialist is experienced and specifically trained to clean an animal hoarder’s house.

Animal Hoarder Cleanup and Personal Protective Equipment

In order to safely undertake animal hoarding cleanup, those involved in the process must utilize appropriate personal protective equipment or PPE. Examples of personal protective equipment for animal hoard cleanup includes:

  • Goggles
  • Mask or respirator
  • Uniform, apron, or smock
  • Disposable gloves
  • Disposable shoe covers

Removing Animals

A preliminary task in advance of commencing the actual hoarding cleanup is to remove the animals from the property. Organizations like the ASPCA or the Human Society can assist you in locating assistance in removing hoarded animals. You undoubtedly will desire to access the most humane resources to remove and address the needs of hoarded animals.

Four Essential Stages of Animal Hoard Cleanup

There are four primary stages associated with animal hoard cleanup:

  • Cleanup
  • Sanitization
  • Deodorization
  • Restoration
  • Cleanup


The animal hoard biohazard remediation process commences with cleanup, following the removal of the animals. This includes the elimination of all biohazardous materials from the premises. This includes blood, bodily fluids, and other biological materials. This includes any items that have been contaminated by these substances. In addition, the remains of dead animals are nearly always found at the premises where this type of hoarding occurs.


The next step taken in the process of an animal hoarder cleanup is the elimination of hazardous pathogens, including potentially deadly bacteria and viruses. This is accomplished through the application of medical grade sanitization agents.


One of the striking things associated with animal hoarding is the putrid, pervasive odor. The entire premises can be fully cleaned and then sanitized, yet the odor will persist. An additional step must be taken involving the utilization of commercial grade deodorizing chemicals. Through this third stage, a professional biohazard remediator thoroughly eliminates the stench associated with animal hoarding.


The final, ultimate, objective of an animal hoarding cleanup is the full restoration of the premises to a habitable condition. This means returning a residence to a condition that it could be placed on the market for sale if that was a goal. If not, the house is placed in a state that the individual who hoarded animals has an opportunity to begin anew. (Keep in mind that merely cleaning up the premises utilizing the services of a professional biohazard remediation service is not, in and of itself, typically enough to ensure that a person doesn’t start the animal hoarding process again.)

Post Animal Hoarding Cleanup

The process of dealing with the issues surrounding an animal hoarder doesn’t end when the four-stage cleanup process is completed, according to the Mayo Clinic. There is more work to be done. The stark reality is that the vast majority of animal hoarders will start the process of accumulating inappropriate numbers of animals even after a tremendous amount of time and effort is expended returning their homes to a habitable condition.

As mentioned previously, animal hoarding is a subtype of hoarding, which is a recognized mental disorder. With that said, animal hoarding typically is a manifestation of some other type of mental health order. These associated disorders can include:

  • Depression
  • Social anxiety disorder
  • Bipolar order
  • Post-traumatic stress disorder (or PTSD)

In order for a person not to relapse into animal hoarding behavior in the future, professional mental health assistance is necessary. The primary court of treatment is psychotherapy, also commonly known as talk therapy.

In addition, preventing a relapse of animal hoarding behavior demands that an associated mental condition, like one of those referenced a moment ago, be addressed.

In addition to assistance from mental health professionals, a person who engaged in animal hoarding may also require other types of intervention. For example, a person who hoarded things or animals is likely to benefit from the resources offered by a professional organizer.

Although it’s impossible to determine precisely how many people may be hoarding animals at any one time, an animal hoarder is not alone. Another resource that a person who hoarded should take advantage of is a support group.

Finally, there are basic techniques that an animal hoarder can undertake in the way of lifestyle changes that can assist in preventing a return to past behaviors. These include:

  • Stick to a treatment plan
  • Accept assistance
  • Reach out to others
  • Keep up personal hygiene and bathing
  • Get proper nutrition
  • Take small steps
  • Do what’s best for animals or pets


Emily Kil

Co-Owner of Eco Bear Biohazard Cleaning Company

Together with her husband, Emily Kil is co-owner of Eco Bear, a leading biohazard remediation company in Southern California. An experienced entrepreneur, Emily assisted in founding Eco Bear as a means of combining her business experience with her desire to provide assistance to people facing challenging circumstances. Emily regularly writes about her first-hand experiences providing services like biohazard cleanup, suicide cleanup, crime scene cleanup, unattended death cleanup, and other types of difficult remediations in homes and businesses.