the average bears needs 20,000 calories a day to build up enough fat for winters
so thats a TON of berries and browse like foods

when I mean GOOD access to foods, I tend to think of if they live near good AG,(corn, beans fields) where they and gorge themselves silly and bulk up FASTER than they can in a forest like setting
this is a big reason PA< bears get so fat at such younger age;'s than most places
easy meals without much out put

when they live in the wild's many times they they burn a lot of the calories they intake, looking for more food, its way harder for them to get fat this way!
not impossible, just not as easy as farm land bears
or rural bears that get a lot of free handout's from people that feed them(very common here in many places bears live near people)

a BIG bear in a farm area can put on 200 lbs from spring to fall
a big reason many farmer dis like them so much, they can do massive amounts of crop damage
my one 50 acre corn field at one farm, on average gets about 4-5 acres of crop damage every time I plant corn there from bears, then add in deer and crows and?/
and I loose about 7+ acres a yr there to critters
some yrs a LOT more
its in a pretty deer/bear rich area