Can animals be trained to spy on individuals?

I recently started working on a secret project and now I have deer moving around my house every morning and evening. To be specific, I've found that it's not just one deer, but a group of four or five deer that take turns each day. I have also noticed that they don't eat grass or anything else, they just stand there and look at my house. These deer also leave in the same direction every time. I'm pretty scared now, are they deer at all, they could be robots that are made to look like deer (https://www.google.com/amp/s/www.nbcnews.com/news/amp/wbna44837414).