Innate or Learned?

The studies show that robins are quintessential birds. Male robins have a colorful breast, and the more the breast gets darker, the more the bird will be attracted. The behavior of robins is complicated, and I want to do an experiment with myself. The experiment that I want to do is I want to see how the robins react when they see a tuft of red feathers on the breast of another male robin enters their territories. Also, I want to understand if the reaction is learned or innate. The studies say that the male robin will be more aggressive displays of behavior and even attack the intruder. By this study, I want to put the robin male in a place that I can watch everything for 1 day. Then, I want to bring another robin male and put it in the same place, and I want to see the reaction that the first robin will do. Next, I am going to do it again to see if the scene will repeat itself or not. Finally, just to make sure I am going to do it for the third time to understand the reasons that why the robins do this. If the robin shows an aggressive behavior, it means that the behavior of the robin is innate. If it is not that, it means the behavior is learned.