Majestic Strength, Warmth in Every Paw

🐾 Mastini Sierra

About Mastini Sierra

At Mastini Sierra, nestled in the Sierra Foothills of Northern California, we are dedicated to honoring and preserving the noble Pyrenean Mastiff — a breed known for its gentle nature, imposing presence, and deeply devoted heart.

While this is our first Pyrenean Mastiff litter, our journey with Livestock Guardian Dogs began nearly 30 years ago, rooted in a deep respect for the role these dogs play in family life and rural living.

Where It All Began

My journey with LGDs actually started before I ever lived in the mountains. At the time, I was raising my small children in a beautiful Victorian home in Alameda, California — but we were preparing to move to 15 acres of remote, forested land. It was a dream come true, but as a mother, I was also deeply aware of the realities: bears, mountain lions, and other predators were very real concerns. I needed a dog that could protect us if it ever came to that.

This was long before Google or social media — so I did what people used to do: I went to the library. I read everything I could get my hands on about livestock guardian breeds, made lists, flagged pages, and started attending dog shows to meet breeders and learn more in person.

The Pyrenean Mastiff was one of the breeds that caught my eye — but they weren’t yet available in the U.S. That search ultimately led me to the Great Pyrenees, and the moment I met them in person, I was hooked. For the next 28 years, we raised and lived alongside these beautiful dogs, who faithfully guarded our family and property. Our Pyrs have chased off more than a few wild beasts over the years and were a constant, calm presence in our lives.

My last Pyr passed away two years ago at the incredible age of 14. When she was gone, I did what I’ve always done: I went back to researching. And this time, I was overjoyed to find that Pyrenean Mastiffs were finally here in the United States.

Our Dogs

Today, I share my life with three exceptional Pyrenean Mastiffs:

• Two imported directly from Italy

• One from Texas, whose dam was imported from Spain

These dogs are everything I had hoped for back when I first read about them all those years ago: gentle, watchful, grounded, and fiercely loyal without ever being aggressive. They are truly majestic — with warmth in every paw.

Our Breeding Philosophy

Our first litter has been planned with great care and intention. Our dam, a strong and sweet-natured three-year-old, has been bred to a U.S.-bred sire who holds a champion title in Finland. I’ve had the pleasure of watching him grow, and I’ve come to admire his temperament, structure, and movement, I am very excited to bring his line into our program.

At Mastini Sierra, our breeding program focuses on:

• Health and longevity

• Stable, family-friendly temperaments

• Correct structure and conformation

• Genetic diversity, to help preserve the breed’s future

We raise puppies in our home with thoughtful exposure to household life, people, textures, sounds, and safe outdoor exploration. It is our goal to produce confident, well-adjusted puppies who thrive as both guardians and companions.

A Lifelong Commitment

I care deeply about where my puppies go — and I believe in building lasting relationships with their new families. Whether you’re new to the breed or already experienced with LGDs, I’m always happy to share what I’ve learned and support you on your journey.

Thank you for taking the time to learn more about Mastini Sierra. If you're looking for a Pyrenean Mastiff who embodies the true spirit of the breed — majestic strength and gentle devotion — I’d love to connect.

📧 mastinisierra@yahoo.com

📍Sierra Foothills, California