A person who loves animals and nature is called a naturalist.
Other terms for loving and having affection for nature are biophile, sylvanophile and ecophile.
A naturalist is a person that has a deep appreciation for the natural world around them which includes both plants and animals.
Biophilia is a term which describes the innate human tendency to connect with nature and living things.
Some people also have a love more for animals than humans as well which is also natural.
Preferring animals over humans is normal and is often the result of you perceiving animals as less capable and more vulnerable than humans.
It can also be that you relate more to the animal and their basic needs and emotions than the complex social dynamics of humans.
Pets often rely on us humans for care and companionship and foster a strong emotional bond which can trigger empathy that is more readily than interactions with unfamiliar humans.
Animals are also easier for us humans to understand and have much less complex needs and emotions, so it's much easier to empathize.
That empathy often extends even to fish, bugs, and other less complex animals.
Philozoic is a term that means being loving or kind to animals.
Being philozoic can also mean you have a tenderness for animals or having a fondness for them.
In rare instances, philozoic can also mean loving one's fellow man or being philanthropic.
Having a love or emotional attachment to animals is also commonly referred to as "being an animal lover".
Being an animal lover describes a strong emotional connection and fondness for animals, often leading people to feel deep affection and care for them, treating them as companions or family members.
People who love animals are often seen as empathetic, compassionate, and caring due to the bond they form with creatures that cannot verbally express their needs.
Interacting with animals can reduce stress, improve mood, and provide a sense of companionship, especially for those who might feel isolated.
The hormone oxytocin is also associated with love and bonding and is released when humans interact with animals, which contribute to the positive feelings of attachment.