In Pa its all about weight probably because we only have a fall season when they are at their heaviest and we (not me) prefer to drag them out whole. But a lot of places it is the skull size that counts, doesn't matter if its spring or fall or whether the bear is having a good year or a bad year, skull size is a consistent function of genetics and age. I've only taken 3 bear but all were B&C and that was deliberate, all taken DIY in Alaska. You see a fair number of bear there and you need to be able to judge if you want to be sure of a trophy size. Judging lone bear isn't that difficult but you need to know the details.
You can look at the whole bear but that may not be a good way to judge a lone bear especially in the spring when they are smaller, it could be a fat sow without cubs. You need to know about the parts. If the face looks like a pumpkin, shoot the bear, it is a jumbo. If the ears appear small on the head it probably is a very good bear, if the ears are off at an angle from the head as opposed to upright like on a dog it probably is a very good bear. If the rear haunches from the side have a LOT of width and it goes down all the way to the feet it probably is a good bear. If the bear looks high but the belly hangs low close to the ground it probably is a good bear, if the bear looks high but there is a lot of air under the belly it probably "will" be a good bear in a few years. By a good bear I mean a mature boar, 5+ years. You can have a lone fat old sow that "seems" big but the ankles give it away, she may be heavyish but won't have the skull dimensions. Sows have thin, more delicate ankles, this leads to their tracks not being as wide as an old boar. Big boar have HEAVY forearms, wide ankles, and heavy paws.
A bears actions can also give clues. Around food (bait) or an opening, if it seems nervous, hesitates looking around, it probably isn't the dominant bear. If it walks confidently into openings, stays in them, takes food without worry, meets some of the physical criteria above, probably gonna be as good as it gets for that area.
Here in Pa, at least during the season, we don't have the luxury of judging multiple bear and deciding which one if any to take. But that is ok because best management practice is to equally take bear of both sexes and all age classes, that is why our trophy quality remains very high, B&C top ten is full of Pa bear, the most of any state. In states where selective trophy shooting is the norm (Alaska) certain areas have seen a significant decline in size and age class of boars over the years, those areas now have gone to a draw system to limit the take.
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