Quite often, I am asked the meaning of one's "spirit animal" or totem. "I have a wolf spirit animal, what does that mean?" This question is always asked by someone who hasn't trained much as a shaman yet, and it's a natural one.
Often they've had a power animal retrieval by someone or been told they have a specific spirit animal by someone. They may have tried to look up the meaning of an animal they have encountered in a guide, like the book Spirit Animals by Steven D. Farmer.
I believe there are two topics which are being confused here: power animals, and omens. I'd like to break the difference down.
In shamanism, a power animal is the spirit of a deceased animal who has crossed over, but who has agreed to work with you on your behalf. Power animals are retrieved through a ceremony conducted by someone trained as a shamanic practitioner.
Everybody has animal helping spirits. A shamanic practitioner can retrieve them for you when you and they are ready.
When you have a power animal retrieved, for example, a crow, you are beginning a relationship with that one animal spirit. To ask about the meaning of having a crow as a power animal doesn't really make sense. It's like asking, "what does it mean that my brother is a plumber."
With power animals, it is all about establishing an ongoing relationship with an individual spirit.
A note here, that all power animals are absolutely amazing. In non-ordinary reality, a mosquito is as powerful as a blue whale. Power animals always come with a great deal of power. It's important not to place human meaning or value on them. Sometimes a person might get a power animal that is from a species they dislike. It's an opportunity to examine and get past that underlying fear or negative emotion.
Again, it's all about a good relationship.
This brings me to the topic of animal omens. Shamanic practitioners receive training in reading and interpreting omens. But interpreting omens are not as simple as looking up the meaning of an animal you see in some book.
Omens are a language of their own. Like spoken and written languages, there are aspects like culture and context which can't be ignored. I may see three crows on a wire one day, and you may see three crows on a wire the next day, but because we are different people with different life circumstances, the omens may have completely different messages.
The Sanskrit language has dozens of words for "love" where we really only a few in English. I can love my children, and I can love a cheeseburger. In each case, the word love means something very different, because the context is different.
Omens are the same. To properly make meaning out of an omen, a shaman would first gather a lot of information about the person and the context. And then the shaman would conduct a divination ceremony to receive guidance and information from his or her helping spirits.