Welcome to the clinic

At Niagara Animal Hospital, we understand that animals are not just pets, but also members of the family. As your family's 'other' doctor we constantly strive to provide the quality of care that you would expect for yourselves. We believe every pet should be treated as if it were our own.

We employ the latest in equipment, from diagnostic equipment, to dental, to surgical, to anesthetic monitoring, to digital x-ray. These things, together, along with our caring and compassionate team provide the best care for your pet.

Please stop in anytime for a hospital tour, or give us a call to answer any questions you may have. Our caring and dedicated team is here to take care of you and your pets!


We are constantly improving our level of care

We regularly seek out training and equipment to make sure we are providing the best quality care possible. From keeping up with the industry through professional books, magazines and websites to vendor sponsored lunch and learns on the latest products and services to large veterinary conferences with thousands of other Veterinarians. All of our pets deserve the best!

We are fellow pet owners

All of us at the hospital are fellow pet lovers; in fact you will probably see a number of our pets when you visit the hospital. Your pet gets the same care and treatment that our pets receive. We don’t recommend products, medications, or procedures we don’t use and believe in for our own pets.

We are a small team with big experience

We have a team of 7 but a combined total of over 46 years of experience providing care to animals. What does that mean? We know our clients and their pets and our team likes to work together. In addition we have a large network of veterinary specialists to consult with when necessary.

Niagara Animal Hospital Staff

Meet our Team

Dr. Aaron Zimmerman, Doctor of Veterinary Medicine

Dr. Zimmerman was born and raised in Peoria, IL. After serving 5 years in the Army as a paratrooper in the 82nd Airborne and 6 years as a Drill Sergeant in the Army Reserves, he attended undergraduate and veterinary school at Madison, WI where he graduated in 2014. He and his wife (Dr. Drake) practiced in several areas (Texas, Wisconsin, and Michigan) before joining Niagara Animal Hospital in 2021.

Dr. Zimmerman has a passion for providing owners with the best information to help them make the right decision for their pets. His special interests include dermatology, pain management, anesthesia, and internal medicine.

At home Dr. Zimmerman and Dr. Drake enjoy spending time with their 2 dogs (Olive, and Orzo), their cat (Ash), guinea pig (Rusty), a young Russian Tortoise (Alice), and an amputee rescue toad named Eileen.

In his time away he enjoys learning, reading and spending time outdoors.

Dr Bissen, Doctor of Veterinary Medicine

Meet our Team

Dr. Theresa Drake, Doctor of Veterinary Medicine

Dr. Theresa Drake received her DVM (2014) and Masters in Bacteriology (2009) from the University of Wisconsin-Madison. She also holds bachelor’s degrees (2004) in Cello Performance (Oberlin Conservatory of Music) and German Studies (Oberlin College).

Dr. Drake was raised in Iowa City, IA, the eldest of three children. As a youngster, Theresa always had a strong interest in biology, music, and language. Before graduation from college, Dr. Drake decided to focus her life goals and education on animal health, which eventually lead her to veterinary school. While working her way through pre-requisite coursework for vet school, Dr. Drake earned a living as a veterinary assistant for several years in both general and emergency practices. She also volunteered at the local animal shelter and worked on two different dairies (one cow, one goat).

As an experienced general practitioner, Dr. Drake has strong medical and surgical skills in many fields of veterinary medicine including preventive care, urgent/emergency medicine, dentistry, and dermatology. You will find an emphasis on quality of life guides your discussions with Dr. Drake as you work together to treat your pet.

Dr. Drake currently shares her home with her husband Dr. Aaron Zimmerman and many pets, including 2 dogs, one cat, a tortoise, a toad, a guinea pig, and several fresh water fish. In her spare time she enjoys playing the cello, crafting, and watching reruns of Schitt’s Creek.

Dr Bissen, Doctor of Veterinary Medicine

Meet our Team

Dr. Heather Bissen, Doctor of Veterinary Medicine

A 2007 graduate of the School of Veterinary Medicine at the University of Wisconsin, I grew up in the La Crosse, WI area and knew from age three that I wanted to devote my life to caring for animals. Throughout much of my life I have been working with and around animal hospitals, animal shelters, and boarding facilities in many different roles. I started volunteering at my local animal shelter at the age of 12; the youngest they would allow for volunteers. There I hugged cats, walked dogs, and cleaned countless cages. I also spent many days during the summer months at the local veterinary hospital, watching surgeries and seeing appointments with our Veterinarian. In my teenage years, I cleaned horse stalls to help pay for my horse boarding, and through my college years, I worked as a receptionist and veterinary assistant at various animal hospitals. After graduating from Veterinary School, I married my husband John and moved to the Milwaukee area. For several years I was an associate doctor for a large and very busy multi-doctor animal hospital. After a few years, I moved on to become the lead veterinarian at a different multi-doctor practice in the area, and for four years I helped them grow and become well known in the community. It has always been my goal to own my own veterinary clinic, so in 2013, I took over as the practice owner at the Niagara Animal Hospital. Having spent a lot of time in the Northwoods near Minocqua growing up, I am excited to call the Northwoods my home.

My veterinary interests include soft tissue surgery, internal medicine and dermatology. I look forward to following my patients from puppy/kitten to their senior years and helping them with the ups and downs along the way. My husband and I have two children, a Golden Retriever named Aspen, and a three-legged cat named Echo. We enjoy spending most of our time running, hiking, fishing, camping and enjoying the outdoors.

When I need to relax, I enjoy baking and decorating specialty cakes and cupcakes, which you will probably see on a regular basis at the clinic!

Dr Bissen, Doctor of Veterinary Medicine

Diane, Customer Care Specialist

I was born and raised in Norway, Michigan, within five miles of where I live now. In 1973, I married Roger, who also has lived in this area his entire life. Our family grew quickly with three daughters arriving in quick succession.

I had always been horse crazy, so it was only natural that we decided to raise and show horses and eventually have a boarding facility. Our daughters' lives revolved around the horses and they enjoyed showing and trail riding. Roger and I have three Keeshond dogs; the oldest, Annie, has earned her Conformation Title and Agility 1 Title and has brought a smile to many faces at the local nursing homes.

Life is quieter now (until the grandchildren come over!) and we have moved from the farm to a nearby home on five acres where we reside with two Arabian horses. It has been a pleasure and a privilege for me to have spent the last almost twenty years at Hometown Animal Hospital and to continue at Niagara Animal Hospital.

Diane, Customer Care Specialist

Ashley, Veterinary Assistant , Certified in Laser Therapy

I was born and raised in Milwaukee. When I was sixteen my family made the decision to move to the small town of Pembine, Wisconsin. I have loved every minute of living in the country as it has allowed my family and me to open our arms to animals that found themselves needing a new home.

I went to Lakeland College where I graduated with my Bachelor of Arts in Psychology. While going to college I also became a certified dog trainer and worked with the local humane society. After college I moved back to Pembine and started working for the Almost Home Animal Shelter. In November I joined the Niagara Animal Hospital and now get to work full time with animals!

Right now I have two dogs (Lacy & Bullet), two horses (Jazz & Niero), and a cat (Lucky). During my off time I spend it with my son doing whatever he wants. During the summer I stay busy at the Norway Speedway with my family, getting them ready for racing!

Ashley, Veterinary Assistant

Myrisa, Certified Veterinary Assistant , Certified in Laser Therapy

I was born in Hancock, Michigan and raised in Iron Mountain. I've lived here my whole life except for when I visited my dad for the summers. He lives downstate in Portage, Michigan where I have a younger half-sister Olivia and a younger half-brother Brady. My parents did split and remarry so overall I have a huge family! Here in Iron Mountain, I have an older brother, Josh and another younger half-sister, Brie.

I graduated from Kingsford High School and a year later took a course at Penn Foster to receive my Veterinary Assistant Certificate. I am very thankful for the Niagara Animal Hospital for letting me be a part of their team. I have always had a big dream of working with Animals, and now I get to meet new clients and their furbabies!

My favorite season is summer. I love doing the normal Up North activities with my fiance like swimming, biking, fishing, boating, floating, four wheeling, and especially riding in the razor! When its cold and rainy I love drawing and playing board games with friends and family, and during the winter months I enjoy snowmobiling.

In July 2014, I met my husband, Dan, the love of my life, and we married in July 2017. Together we have three very spoiled boys: a chocolate lab named Browning, and a shepherd/pitbull mix named Jenx, and a husky mix named Yukon. We love taking them on long walks, bringing them camping, and taking them swimming on the boat. They all have very different personalities but are loved equally!

Myrisa, Veterinary Assistant

Brooke, Certified Veterinary Assistant

I grew up in Niagara, and enjoy living in the northern parts of WI. I have always had animals in my life and will always have them. Ever since I was little, I knew I wanted to work in a vet clinic to help the sick animals. With my passion for animals it makes work exciting and enjoyable.

I graduated from Niagara High School in 2016, then moved to Wausau, WI, for my college education. I got an Associate’s Degree in Veterinary Science at Northcentral Technical College. I graduated in May of 2018, and then moved back to Niagara right after graduation. I really appreciate the small town of Niagara, and all the caring people that live here.

I grew up with a lot of animals in my life and many of them have been different species. I have had bunnies, chickens, ducks, dogs, cats, and lizards. All of them were so close and dear to my heart. My dog, Diva, in the picture above was my very first pet of my own. Her favorite activities include sleeping and playing in the snow. Finley is my cat, also in the picture above. He was my college animal and he enjoys spilling all my water glasses at home, and watching for birds. I also have a Plotthound named Gemma. She does not sit well for pictures, but her favorite hobbies include going for walks and playing soccer. I enjoy hunting, fishing, four wheeling, camping and walking. If I am not spending time with my loving animals, you can find me in the woods.

Brooke, Certified Veterinary Assistant

Courtney, Veterinary Assistant

I was born and raised in Iron Mountain, Michigan for most of my life. I graduated from Iron Mountain High School in 2012 and then soon after in 2014 I moved to Virginia Beach and lived there for a little over 4 years. While I loved being on the coast in Virginia after those 4 or so years, I moved back to the U.P. Shortly after moving back I completed an EMT training course while working full time.

I have always been around many different types of animals from a young age. Going out to the farm with my grandparents was one of my favorite places to be as a child. I then started working with horses by 8 and from ages 14-16 I worked as a Jr. Wrangler and showed horses during the summer at the fair. My whole childhood I was around cats and dogs. I even had a rabbit for a few years. I now live at home with my daughter, Salem, and our little ball of fluff, Gizmo. Gizmo is our chinchilla.

When I am not working, I really enjoy anything to do with being near the water such as; jet skiing, kayaking, tubing, swimming, fishing, biking, hiking, and camping. Being around family and friends is very important to me. I also enjoy cooking and trying new foods or new restaurants and breweries.

Courtney, Veterinary Assistant

Tiger, Animal Client Relationship Specialist

My name is Tiger and I am the clinic cat. During the day I stay busy conducting frequent inspections of the building (how do those cat nip balls get scattered around the clinic anyway?), and reporting on the best lounging spots. Typically I dress up for the holidays. A cat has to look his best when his friends come in!

Generally you can find me on the front desk checking in shipments and organizing appointments as they come in. I have a big job but it's very rewarding when my hard work puts a smile on a sad face. To keep this place upbeat and fun, I organize a daily game of hide and seek. There are so many hiding spots, my co-workers would never find me if I didn't throw out a meow hint every now and then.

When late afternoon rolls around I move to the back of the clinic so everyone knows it's time to start cleaning up and preparing to leave for the day. I sleep in the guest room of the clinic with any animals who are staying overnight and keep them company. Usually just before bed Dr. Bissen checks in with the wall mounted camera and I give her a report on how everyone is doing. I love my job!

Tiger, Animal Client Relationship Specialist