I'd say you are more likely to collect Bigfoot pee these days than that of any dinosaur...

The whole urine as a deterrent thing is a bit pavlovian, in that the scent has to be associated with a known threat, thus my previous statement that where you are on the food chain will determine what sort of pee you will be afraid of. Bears being at the top of the food chain in the natural environment aren't going to be scared of much else except maybe another bear, and yes, bears mark territory as well, using all sorts of excrements. Typically bear scat is the most telling sign of the size of a bear; the bigger the pile, the larger the bruin that made it. For that reason, I prefer to eat heartily while playing out in the woods, thus being able to leave a mark that would "scare a bear", heh heh heh...