okay, got a bit of a situation here, and wanted to know what the cause might be, and any possible solutions.
I keep Biscuit at Mike's house (he has more room than I do right now, and I spnt almost the entire summer there anyways). he's happy there, and able to get out of his cage for a couple hours everyday to run around loose in mike's bedroom. but, the last couple weeks, we've noticed a problem. Every once in awhile, Biscuit doesn't want mike anywhere near him. It started with hissing, and puffing up his throat when mike would come near, or try to take him out (not every day, mind you, just once in awhile). but, today, i was talking to mike after work, and it's prgressed to the point where biscuit tried to bite him a couple times this afternoon

. Again, these temper tantrums aren't often, and are only towards mike, usually when he's trying to get Biscuit out of his cage.
my question is, why is he doing this?
I haven't been able to get out there as much the last 2 weeks, due to work and now school (it takes me an hour & a half to get to mikes on the bus), so I don't know if that could be part of it. Also, we've noticed that it's about time to start that new enclosure for him, as he's getting cramped for space in his 33g setup now (though he still has room to run around a bit, and swim in his pool). He's been scratching at the glass whenever he sees me, so that i'll let him out in the daytime. we've been trying to keep him out for longer periods of time, even putting heatlamps etc. in his favorite spots to keep him cozy. What could be causing this sudden aggressiveness, and why only to mike?
if anybody has any clues, please let me know!!