Dos B sum Big Cats. :)

Bison are the most aggressive animal in Yellowstone and most injuries in the park are caused by them:

Study - Bison goring injuries: penetrating and blunt trauma
Injuries from bison Bison attacks have not previously been reported in the medical literature. This study examines 56 bison-caused injuries, including two fatalities, from Yellowstone National Park over the past 15 years. Two mechanisms of injury were observed. The first was direct goring by the bison's horn, “hooking,” resulting in deep puncture wounds most often to buttocks or thighs. Abdominal injury, including evisceration, was also seen. Blunt trauma occurred as the victim was shoved or butted by the animal's head, or when the victim sustained a rapid deceleration on ground impact after being tossed into the air. Multiple sites and types of fractures, abrasions, and contusions were seen. Most patients requiring hospital care for goring wounds were treated with operative debridement and primary closure. Cultures of puncture wounds were uniformly negative. Injuries from bison exceed injuries from bears or any other wild animals in Yellowstone National Park.

(from http://forums.yellowstone.net/viewtopic.php?f=4&t=10970 )

I do believe (on the basis of the <i>Journal of Wilderness Medicine</i> paper quoted above, among other sources) that bison cause more injuries to humans in Yellowstone than do animals of any other single species.

I don't believe that bison are the most aggressive animal in Yellowstone, or that most injuries in the park are caused by them. I'm no expert, and I'm willing to be convinced otherwise, but if I'm going to stumble upon a wild animal on my hiking trail, I'd prefer a bison to a grizzly bear.

Here's a link to the whole JWM paper, in case anyone is interested: http://download.journals.elsevierhea...5994711372.pdf

Simple Q: Are there more Bison or Griz/Black Bears in Yellowstone - and how many human interactions with each?

My guess is the Bison by far.

And just to compare - an adult Griz (a Brown Bear) is about 1/3 the size of a Bull/Bison - say 700/800 pounds to 2,000 to 2,500. So if a Bison hits you with any kind of momentum - you are like a leaf in the wind, and can be seriously injured just hitting the ground.

Still - having more familiarity with hoofed animals (we raised beef) - by far than I do with Bears (never saw a bear in the wild all the time I camped/hunted growing up in Oregon) - coming across a Griz - or even a Black Bear - on a trail - would cause one to seriously soil your underwear.

With Bison - I think you can normally see them - and stay far enough away not to threaten/disturb them - unless of course you are a tenderfoot dummy - but a bear can suddenly appear out of nowhere, perhaps hungry - or perhaps guarding a kill - or worse yet - because a cub had wondered away.

Again, you would encounter a bear probably much less frequently than you would see a Bison - but dang - even though the hunting experts say hold your ground if a Bear charges - as to flee encourages their attack a predator/prey instinct/give chase - not sure I could remain that cool. :)

hmm, I have had close encounters with bison, elk, moose, and black bears. Bison are easy--just give them LOTs of room and you don't usually encounter them in heavy brush. With moose, I have frozen in fear and waited for them to take their own sweet time deciding where they wanted to go--or swung really wide through the trees to stay away. Elk--as long as not a male in rut, it isn't a problem and you know where those are by the bugling. The black bears I saw were more interested in turning over logs to get grubs. But again, the freeze, gently let them know you are there, and let them decide what to do worked fine.

In all my years back packing Yellowstone, I always had a sheep bell and never encountered a grizzly. My dad seems them a lot when salmon fishing in British Columbia--but they are so busy feasting on salmon they don't care about people. I would prefer not to see one up close and personal.

As for cougars--no thank you, no thank you. They sometimes follow the deer down into the foothills here. I am always looking for signs when I go out running in the winter. So far I have been lucky!!

And rattlesnakes, sigh..I am a snake magnet. I simply can't go near the trails after 8 am during the months of May-September. I have to go up higher in the mountains. I can even tell the difference between a gopher snake and a rattler on the fly as it were. Although my subconscious kicks in when it sees the pattern and I still find myself attempting to set the world record for a standing broad jump!!!!!

It seems likely that there are more bison injuries due to a couple of facts

1) there are many more bison than there are bears or mountain lions

2) bison don;t hang around in the woods or on hiking trails - they live in open territory which means that a much large number of tourists come in contact with them

3) many of the contacts are near roads - so bison are much more likely to come into contact with people who are unfamiliar with wild animals

We were at the Mormon Barn in GTNP about 3 years ago when a herd of Bison came over. They were way over in the meadow when we got there, so thought they wouldn't bother us, but came to the barn area a few minutes later. There were 4-5 people perched up on the loading ramp until the bison decided to move on. There were mothers and calves and bull bison, but they didn't seem to be upset at our presence, but we stayed as still as possible not to frighten them.

Here's a little footnote for this thread:

Press Release from Olympic National Forest - July 3, 2012:

Olympia, WA – To ensure public safety, an emergency closure has been implemented on the Mount Ellinor Trail #812, located on the Hood Canal District of Olympic National Forest, approximately 18 miles northwest of Hoodsport, on Forest Road 2419. Several aggressive mountain goat encounters have occurred in the past two days, prompting this action.

http://www.fs.usda.gov/detail/olympi...TELPRDB5378128

LOL. Yes, Billy Goat Gruff can get a little nasty when he wants to. Goats are far more agile and can outmanuver/head butt a Mountain Sheep that may be bigger.

Why is this thread starting to sound like "my animal is meaner than your animal"?

Hope it's not boring you gail - but some of us like it. :)

The information leaflets available or posted warnings at national parks are pretty easy to understand: Bison have poor vision, so you can actually surprise them even when you think that they should see you coming. Especially if you approach them against the wind.
If you are still not sure how much care bisons take where they run when they get into a stampede, visit one of the many buffalo jumps up there.

I guess many people cannot understand that places where they are allowed to go to are not made 100 pct "safe" for them. And that there are places where they no longer are on the top of the food chain.

Common Sense rules. I was scared to death when I had to ride a snowmobile past a huge bison. I quietly went by and the bison did not even look my way