While I wouldnt call that urine spot 100% conclusive, that is a track I wouldnt give up on after seeing it... especially when tracks are a bit scarce. It does look like it could have been from a bull, a couple things I try to look for when I find a urine spot in the snow:
Is it possible to see from the tracks where the animal stood while it took a whizz? If you can figure this out it will clear things up right away. Any little dribbles and their location relative to the main spot can also help.
Are their any droppings, if so what is their location relative to the pee? Along this line, when I find droppings I look very carefully for any small amount of urine that might have been dropped when the animal crapped. If you can find evidence of pee near the droppings you are most likely on a cow track, if you have some dribbles ahead of the poop it could be a bull.
Too, watching how the animal moves can help, does it steer clear of tight openeings indicating a rack? If it does go through a tight opening can you find evidence of the rack knocking snow off the branches etc?
In the end, its about 60% voodoo trying to say for sure the sex of an average size animal if you cant get an obvious pee spot. The last bull I tracked pee'd 3 times and none of them were conclusive, it also went through some tight spots and never knocked any snow down... worst of all I could feel just a tiny bit of breeze on the back of my neck. For various reasons I stuck with the track, tryed to move fast enough that the breeze wouldnt push my scent too far ahead of me whilst attempting to still scrutinize the bush thoroughly... about a kilometer later we had our bull.
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