Hmm. I'd take him on a 10 mile hike and then see if he was still interested in the mirror.
Current Carry: Skookum Dog Citizen Canine prototype, Founder's Briefcase (every day carry), Small Cafe Bag (every day carry), Shop Bags (groceries, extra random stuff), Aeronaut 45 (travel), Synapse 19 (day hikes), Smart Alec (longer day hikes), Skookum Dog Road Duffel (Medium) (travel), Clear Organizer Wallet, Travel Stuff Sacks, Organizer Cubes
The dog thinks that there is another dog, (he makes play posture at the mirror).
He doesn't recognize himself in the mirror.
It is always a problem with most animals, especially fish and especially males.
Only great apes, dophins and elephants have been known to recognize themselves in the mirror, humans too.