Len Mastaler | Navigating Breed-Specific Legislation (BSL) in Canada: What Prospective Bull Breed Owners Need to Know

Len Mastaler of Highwood Kennel is an experienced dog breeder who believes bull breeds can make exceptional family companions when they are responsibly bred, thoughtfully raised, and matched with the right homes. His perspective offers a compelling challenge to breed-specific legislation (BSL): rather than judging dogs by their appearance, we should focus on the people who raise them, the environments they grow up in, and the behaviours they demonstrate.

When a Breed Becomes a Label

Pit bull-type dogs have undergone a remarkable transformation in public perception. Originally bred for blood sports, dogs associated with these types later became beloved family companions and cultural icons in early 20th-century America. Decades later, associations with illegal dogfighting and sensationalized media coverage helped recast them as symbols of danger.

In Ontario, that stigma became law.

In 2005, amendments to the Dog Owners’ Liability Act (DOLA) introduced restrictions targeting American Staffordshire Terriers, Staffordshire Bull Terriers, American Pit Bull Terriers, and dogs deemed to possess substantially similar physical characteristics.

For Len and many fellow Canadian Kennel Club (CKC) breeders, the problem lies in the premise itself: a dog's appearance is not a reliable measure of its temperament or potential for aggression.

The term “pit bull” is particularly contentious because it is often used as a catch-all label rather than the name of one clearly defined, universally recognized breed. When legislation relies on physical resemblance, registered purebred dogs and mixed-breed dogs can face restrictions based on how they look, rather than their genetic background or individual behaviour.

The result is a system that can leave owners, shelters, and enforcement officers navigating difficult questions about which dogs are covered and how the rules should be applied.
The CKC opposes breed-specific legislation, advocating instead for breed-neutral laws that hold owners accountable and address dangerous behaviour on an individual basis. Len shares that vision.

It’s Not Just the Dog. It’s the Hands It’s In.

For Len, the conversation about canine safety needs to move beyond breed stereotypes and toward responsible breeding, early socialization, training, and owner accountability. He believes bull breeds can be among the best family dogs. But he also recognizes that raising a confident, well-adjusted dog requires more than good intentions.

It begins with the breeder.

At Highwood Kennel, puppies benefit from a loving home environment, clear boundaries, and deliberate exposure to the world around them. Len incorporates early neurological stimulation and carefully planned sensory experiences into his approach, including introducing puppies to sounds such as sirens, wind, and thunder.

The thinking is straightforward: unfamiliar experiences can be unsettling for dogs, and thoughtful, age-appropriate exposure can help puppies become more comfortable navigating the world and reduce fear responses.

Len also raises other breeds and participates in dog shows, giving his dogs opportunities to experience socialization in various environments.

His broader point is that temperament and behaviour develop through a combination of genetics, early experiences, training, and the environment a dog lives in. No breed is a substitute for responsible ownership.

The Art of Matching the Right Puppy to the Right Home

One of Len's most important contributions as a breeder happens before a puppy ever leaves his care: matching each puppy with a household suited to its temperament.

He prefers prospective owners who are open to either sex rather than arriving with a rigid preference. Why? Because the individual puppy matters more than checking a particular box.

A highly driven, energetic male, for example, may be a poor match for someone seeking a quiet companion who will spend most of the day relaxing on the couch. Another puppy from the same litter might thrive in that very home.

Len typically evaluates puppies for placement around seven to eight weeks of age, when their individual personalities are becoming more apparent. This allows him to consider their emerging temperaments alongside each household's lifestyle, expectations, and experience.

That process reflects a principle that applies to every breed: responsible breeding isn't just about producing healthy puppies. It's about helping those puppies succeed in the homes they enter.
Reputable breeders invest in understanding their dogs, educating prospective owners, and making thoughtful placement decisions—even when that means advising someone that a particular puppy isn't the right fit.

A Better Approach to Public Safety

Len's perspective also highlights a broader question: if dogs of any breed can develop behavioural problems when poorly managed, is targeting appearance the most effective way to protect the public?

Dogs need appropriate socialization, consistent training, boundaries, and owners who understand their responsibilities. These needs don't disappear simply because a dog belongs to a popular or familiar breed.

Ontario's approach stands in contrast to the breed-neutral provincial frameworks found elsewhere in Canada, where dangerous-dog rules generally focus on a dog's behaviour and circumstances rather than a blanket provincial prohibition based on breed. Specific rules and municipal restrictions can still vary by jurisdiction.

For Len, the way forward is not to dismiss public safety concerns, but to address them more directly. Individual dogs that pose a demonstrated risk should be managed appropriately, and owners whose actions put others in danger should be held accountable.

At the same time, responsible breeders should be recognized as part of the solution and not overlooked in a debate dominated by stereotypes.