Mainspring, I agree with what you are saying but I would rather have a handgun on my hip than a rifle/shotgun leaning against a tree or rock...
Let me make it very clear that not all wild animal attacks are full out charges towards you...
With that said... I very rarely go out without a rifle or a shotgun with me as well but I know I will be putting them down when I get to where I am working.
A few of these are a 20" barreled LSI Puma M92 in 454 Casull, a Marlin 1895GS in 45-70, a Rem 7400 30-06 carbine and a 14" barreled Rem 870 and a 18.5" barreled Rem 870 12 gauge shotguns
I have spent an enormous amount of time researching, loading and shooting appropriate rounds for them and I have done the same with handguns.
I will take my 45-70 before a shotgun any day though...
Let me give this another approach. My totally anti-gun Canadian Federal Government licensed me to carry handguns for defense against wild animals.
If an anti-gun government will do this there most definately be proof that handguns can and do work to defend ones life from wild animals.
Are handguns the best tool for the job most definately
not but the way I look at it the tool you have with you is the best tool to have and I am never without a handgun when in the bush.
Depending where I am or what time of year I carry different handguns/cartridges.
When the bears are sleeping for the winter (they actually do that here
) or if I am jumping in and out of my truck my prefered handgun is a Glock 20 10mm with 200gr Beartooth WFNGC's @ 1300fps. I also carry 5.5" s/s Ruger Bisley Vaquero's in 45 Colt with 300gr XTP's or 330gr WFNGC's @ 1280fps.
My theory on this is that I can load/unload this handgun faster so will have it with me if a need arises (here in Canada it is illegal to carry a loaded firearm in a motorized vehicle). Also when the bears are asleep for the winter my main concern is mountain lions. We also have more mountain lion attacks here than anywhere else in the world so planning a defense against them is totally advisable.
I have had two buddies that have been attacked by mountain lions fortunately both were able to shoot them while the lion was leaping into the air . In both cases the guys where hunting the first one shot the M/L with a 7mm Rem Mag and the second was a 270 Win both animals dropped instantly.
If they had handguns the first would have been extremely hard to hit witha handgun because it was attacking when my buddy heard it running at him from behind the second was spotted lying in wait with it's ears flattened against it's head and it's tail twitching much like a house cat will do.
This one didn't give much more time than the first one but wasn't running when spotted.
While I'm at it let me clear up what a bear charge is like. Yes there are full out running attacks but the majority of black bear attacks are slow wandering in on the victom giving tons of time to be able to draw and place your shot accurately.
I have had to shoot 3 black bears in defense the first one I used a 308 Norma Mag and shot the bear at about 8 yards as it was running at me. The next two where with my 7.5" Ruger SRH in 454 Casull before I had it cut down to the 4.25" gun I posted above. I used a 360gr C/P WLNGC @ 1520fps on the first one and a 240gr XTP-Mag @ 1900fps on the second one...
The first bear was walking up hill towards me and when it swung it's head to it's right I shot it in the neck with the bullet breaking it's spine between it's shoulder blades. The second was more of a side chest cavity shot that hit a bit high but broke it's back dropping it instantly the bear continued to try and drag itself with it's front legs but I ran up to it and gve it another 2 quick shots one in the lungs and the other in the neck.
I'll end with handguns do have a place in the realm of firearms for defense. Get out to your range and practice using those guns so that you are as proficient in their use that you can possible be.
edit to add...
If I was to carry a 500S&W these would be the loads I would be working with...
http://www.kdm-custom-bullets.com/photos.html