Fixation on cat's path
I've read lots of great info on this forum over the years and decided to jump into the conversation with an issue that I've had trouble resolving. I tried searching a few times, but couldn't find any threads so I apologize if this has been discussed already...
My five-year-old German Shepherd had never seen/lived with a cat during the first 3.5 years of his life. He has a very high ball and prey drive, but generally listens to "leave it" commands.
If I say the word "cat" or make the noise we use to call the cat, he immediately gets anxious and starts patrolling, whining, etc. When I bring the cat out of her room (we have a baby gate in the doorway so she has a safe spot), he'll come up to me and sniff/lick her very quickly, then immediately lay down on the floor and fixate on our hallway (when I let her go, the cat usually runs out of the living room and kitchen, then through a spare bedroom and across the hallway to her room). It doesn't help that the cat is extremely skittish and runs at the first sight of the dog, or if she thinks I'm going to bring her out if he's not crated.
The dog won't relax until the process of the cat running across the hallway and into her room is complete; even if I sit down with the cat right next to his face, he won't look at her and is more worried about watching the hallway than anything. If I hold the cat and stand in the kitchen, he'll stare down the stairway or hallway seemingly hoping to catch a glimpse of her running back to her room.
Has anyone experienced this? Why is he so locked in on where the cat should be/will go and not where she is? He never seems to be in attack mode, but the cat is very skittish and runs as soon as she sees him, which inspires the chase. The few times that he did actually look at her, it seemed like he was in a rough play mode (he tried hard pawing), but I've been careful to avoid testing his true intention.