The bear looks very thin to me and since the picture was just taken it makes me think it is a fairly young bear. Bears this time of year are putting on the body fat to prepare for winter. It is always hard to judge them unless there is something in the frame that is a known size. Most large or mid sized bears I see here in Vermont have low hanging bellies and small looking ears as compared to the head. From the pictures I could see on this post the only real good look I got was the high belly. I tried to gage the tree size by the leaves and growth all around it since it was taken in a northern climate similar to here. I can believe the tree is 18" but my initial guess was 12" but that was thinking the logs were smaller than what the poster says. Around here lots of bears are taken at less than 150 pounds and are not cubs but rather 1 1/2 year old bears. My figures were assuming the bear was in that age class. Most young bears look lean and long since the belly is so high. Judging them in the woods is always tough and my experience with it is they always look bigger than they are. If you are hunting from a stand with bait like they do in some states then you generally get to see several with the bait barrel there so you have something to judge by. Here we have to hunt them like deer with no baiting so they often are moving and you have to decide pretty quickly whether they are shooters or not. I always like to see sows with cubs and that gives you an idea of how large they are. Not that I would shoot a sow with cubs but they are a privilege to watch. One of nature's finest creations. A 250 pound bear (dressed weight) here in Vermont would be a really nice bear. They get a couple of hundred pounds heavier here but that isn’t the norm. I would say most are in the 100 to 200 pound range and are 1 1/2 to 3 1/2 years old.