Bear Spray in the Park is Legal
I just got a reply from the NPS and Bear Spray is currently legal to carry in the park. THEY, AND I, caution using it indiscriminately as a last resort. This stuff is an oil based mist that hangs in the air and can blow back on you. It is recommended that a quick burst (1-2 seconds) is used, then assess the situation before using again. A cansister carries about 12 seconds of spray. Again this should be a last resort only after everything else fails. THIS IS NOT SOMETHING YOU WOULD WANT TO USE UNLESS YOU ARE ATTACKED it is only effective at very close range! It has be be spray into the bear's face, spraying around your campsite, etc. does not work. *
For those of you who venture to the Yellowstone area, it is NPS and Forest Service highly recommend you carry it in Grizzly areas, which is about everywhere there.
The bears add greatly to the experience of being in the park, if a person does what they are supposed to almost all the bears are harmless. I've said repeatedly that I would probably have to use it on a dog long before a bear.