Tuesday, May 5th, 2009

So, here’s my last post on this topic… for now (there will never be a last post on this topic).

  • Yosemite has gone through its fair share of food lockers. One of the first years I worked here, I read about new food lockers at White Wolf. A week or so later, I heard about how the bears had figured them out already. This is a long and continuing tradition in Yosemite. The other long and continuing tradition in Yosemite is people not figuring how to properly latch the lockers (this is actually the bigger problem). Some locker designs were so complicated (to keep bears out) that people couldn’t figure out how to get the latch(es) closed properly, resulting in the bears successfully playing with the latch(es) and getting lots of food. This continues to be one of the most common food storage problems we see in campgrounds. The latest locker design we use is really simple and we surely see these left open a lot less often than some of the older ones, but they’re expensive to replace.
  • Traps. OK, so, we aren’t trying to keep bears out of traps, but the presumption is that they’re “bearproof” once the bear is inside. Not so. White 60 (previously known as Blue 6 and Blue 10) seems to have figured this out. A trap was set at The Ahwahnee several nights and the wildlife crew found, several times, that the trap was closed, the bait bag was gone, but the bear wasn’t inside. One night, they saw White 60 in the parking lot and chased him away (as is the usual practice, to keep bears wary of people). They chased him up into the rocks, presumably along the bear’s typical route, and started finding their bait bags. No one ever saw it happen, but the speculation is that this fairly large bear was able to snag the bait bag while keeping his feet out the back of the trap, preventing the door from closing. He’s been trapped since, so either he forgot this trick or our bait bag technique is different (which, come to think of it, I think it is).
  • This is one of my favorite stories about one of my favorite bears, Yellow 53 (aka Yellow 54, Yellow 44). A few summers ago, we all started noticing an increasing number of cars with doors open in the campgrounds late at night. At first, it seemed like the usual randomness that happens at night–someone gets up to get something from their car but is too tired to remember to close the door. But, when we started seeing multiple cars near each other with multiple doors open, we started getting suspicious. Another ranger was driving through the campground one night and saw Yellow 53 walk up to a car and open up the (unlocked) door using the door handle. Most of these cars didn’t seem to have food in them, so I think this was becoming a part of his normal foraging activity since it was so easy to do. It’s a really good indication of bears’ curiosity. As to how he figured this out, I think it was a combination of his familiarity with the concept of a latch (see 1st bullet) and him having spent a lot of time at the edge of campgrounds, watching people.

So, that’s all for now. I’ll probably have another story soon…

My last post got me thinking about other “bearproof” things bears have gotten into. Here are a few examples:

  • Bear canisters (we actually call these bear resistant). Many (if not most) brand new canisters that have been tested mechanically and with zoo bears end up failing when wild bears get their paws on them. Usually, these problems are easily remedied with minor modifications, but it’s still intriguing. The venerable Garcia canister, which has been around for close to 20 years, has had surprisingly few failures. But, it just doesn’t hold up to a bear banging it against a rock for 45 minutes (Orange 19 provided us with that information). Another bear, coincidentally tagged Orange 91, rolled several of a group’s canisters into Illilouette Creek.
  • Looking into a "bearproof" dumpster

    Looking into a "bearproof" dumpster with a bear inside

    Dumpsters. The iconic “bearproof” dumpsters scattered all around Yosemite, with the distinctive “half dome” top, worked great for many years… until, in the 1990s (or late 1980s?), wildlife techs began looking inside and finding bears trapped. It turns out that empty dumpsters are hard to get out of (full dumpsters are easy to get out of: less reaching required). Bears have been trapped in them without anyone finding them, resulting in a bear dying over the winter and another who ended up wandering around the Mariposa County landfill. A few bears have (spectacularly) escaped from trash trucks after being dumped into them. In any case, now dumpsters have clips (but not everyone bothers to use them).

  • Trash cans. The half dome trash cans are also all over Yosemite (although a bit less so now than in the past). When they’re too full, bears can get into them. They can also (when not installed correctly) knock the cans out from the “bearproof” part, or, when not closed correctly, can flip up the “bearproof” part.

That’s only half my list… I’ll save the rest for later.