Do animals have souls?
Yes, they do, but they are more in tune with nature than we humans and tend to go back into the cosmic "soup" of nature rather than attempt to return to the physical world to communicate as human spirits do. Everything, people, animals, plants, fish are all connected through the life force and all recirculate into it but at different times and different ways.
Spirits of humans are often still connected to loved ones in the physical realm and attempt to reconnect. Animals are sometimes connected to humans and do try to reconnect, but they do not have the same ability to communicate just as they did not have speech in life. But often they do check in on us. Particularly the pack or social animals. The issue is that their owners often don't know how to listen to them, so it is more difficult to connect with an animal spirit. But sometimes you will get a message from them in a very personal way.
Animals are also more connected to nature and the life energy that connects us all and they find it easy to go back into the cosmic soup to be reincarnated as something else. Often a higher life form. So many times they just allow their spirits to go to the other side and become something more than they were before.
This may not necessarily be human as there are many, many forms of life on this earth and some who enjoy quality of life equal and at times even better, than ours.
Look at pods of Dolphins and Whales, that have a strong social life and few worries.
So animals do have spirits and yes they do often come back to check on their beloved owners, but often better things are waiting for then which they happily embrace.
If your beloved pet has passed on it is OK to build a shrine to it and attempt to communicate with it. They will hear you, especially if you were very close and love one another in life.
They usually do not come through well in channeling sessions as once again there is no speech. So I do not channel animals but I do sense them, the presence of their spirits from time to time..
However, they do not seem to stick around as long as the spirits of humans who have departed this life do.
But they do come back sometimes. And they do feel that attachment to those who loved them and who they loved in return.