Don't let people like him wear on you. There are all kinds of people with irate personalities that think they should be considered the "hobby" police, or a professional on the forum. Just look and laugh. If it happens again, get a hold of the mods and have it situated.
Honestly if the guy keeps something like this up with you, pull a case of harassment since he would be considered as "following" you. At the end of the day think of it this way....you're the one with the gorgeous animals and he isn't. Big or small, people always come across others that for some reason or another, have to attack, degrade, or try to make an example of someone for who knows why. Its like they have to prove who has the bigger e-Pene.