Reading this topic, another question came to mind,
Early in the series some of the Anirmorphs identified an 'unidentifiable smell' in humans we knew were Controllers. I think Jake/Homer, wasn't aware of it, but picked something up in his brother. And Rachel/Fluffer Mc.Kitty caught something in Chapman's scent. I like to think that it was the scent of the Yeerk Pool complex. Most of their morphs had pretty acute olfactory. Cassie ceratinly DEFINATELY could have picked up the enemy's scent with her wolf morph.
Now, could these animals' senses not have been further used to identify Controllers? Like, do a morph to safely tick or cross their parents and close ones? Instead of stalking them every 3 days??