The Question: We have a bird nest in our backyard that was made by a cardinal. Recently, we noticed that a robin seems to be hovering around the cardinals’ nest. The cardinals seem upset by this, and seem to work as a team to keep the robin at bay. Can you explain what is going on?

Submitted by: Laura R.

The Short Answer: Laura, most likely the robin is waiting for the cardinals to make a mistake so it can raid their nest, either to steal nesting materials, or more likely, to steal eggs or baby cardinals. Birds are constantly looking for opportunities to raid nests. It’s a hard fact of life that eggs and baby birds are a much sought-after treat. I’ve seen sparrows chase blue jays, blue jays chase crows, and crows chase hawks. Everyone’s babies are at risk. To make matters even worse for baby birds, squirrels also often raid nests.

Parent birds must be ever vigilant.

For an update to this story, go to this post:  Will Robins and Cardinals Share a Nest?