While Sci was listening eagerly to Kate Clancy's appearance on Skeptically Speaking last Sunday (you'll be able to download the episode soon), I was flabbergasted to find out that there is a rumor out there that, if you go out hiking on your period...you might attract BEARS.
(I totally forgot about this until someone on Twitter pointed it out. Awesome)
Not only that, the rumor was apparently widespread enough that someone actually did a study to find out if it was true.
Which is good, I'd hate to fear for my life while hiking because I'm shedding my uterine lining. I'd like the think bears are more sensible than that.
But I'll admit, a part of me was a little worried. After all, I have been camping, and had our campsite raided by bears, because someone left their toothpaste out of the bear box. Apparently bears in Yosemite National Park love them some minty freshness. And if toothpaste is on the menu, why not tampons? I mean, bears will eat most anything, right? Luckily, science is here for us, and science wants us to know, it's ok to menstruate around bears. Black bears, anyway.
Rogers et al. "Reactions of black bears to human menstrual odors" The Journal of Wildlife Management, 1991.
So apparently this whole fear of bears loving the scent of your menstruating ladybits comes from an attack on two female hikers in 1967 by grizzly bears (today I learned the scientific name for Grizzly is Ursus arctos horribilis, how apt) in Glacier National Park. The women were both apparently menstruating (no one has the original source for that information, though, and neither girl lived to tell the tale). This made people panic, and people actually issued warnings to not hike in bear country while menstruating, even though both attacks took place where there was lots of trash around to attract bears for tourists, and several reviews of major deadly bear attacks have stated there's no evidence for menstruation being involved.
But apparently it depends on the bear. The paper states that polar bears will willingly nosh on tampons soaked in menstrual blood and ignore tampons with normal blood. I'd like to see that one replicated, since there's no record of polar bear attacks being associated with menstruation either.
Anyway, this paper concerns black bears. These are by far the most commonly sighted by hikers, occurring throughout North America. I've seen a few of these myself (free tip, hiking friends, do not pose your children next to the adorable bear cubs for a photo. I have seen this happen). The authors took 15 used tampons (no record of how old they were or if they kept them fresh, or how long they were in), and presented them to a group of 5 black bears feeding on a trash heap. Via fishing pole.
They attempted to get the tampons (which were in a bunch) as close to the bears as possible, and then observed whether the bears picked tampons or trash. They considered the tampons "paid attention to" if the bears 1) ate them, 2) sniffed them with interest, or 3) rolled on them. They did this again with another group of used tampons, these first frozen and then thawed (mmm).
For their second experiment, they took 6 used tampons from 6 women. They went to a spot where people commonly attracted black bears with corn (and hand fed them, no less), and manually presented the tampons to the bears.
Then, they laid out 4 used tampons, some non-used tampons, some tampons with human blood on them (not menstrual), and some tampons with beef on them, and put it by a well used bear trail. They had 12 bears stop on by, and watched what they did.
Then they did something REALLY wild. They had 7 menstruating women HANG OUT with bears. The women hung out near the bears, even hand fed them (the bears were apparently well used to this). And they watched to see how often the bears sniffed at the women's ladybits. I'm not kidding. They first had seven ladies hang out with bears, and then they had one hand feed bears on and off her period for two months (wearing pads, not tampons). Would you hang with a bear for science?
For all of tests, with menstruating women or used tampons...black bears don't care. Regardless of mating season, the sex or heat state of the bear, the freshness of the tampons, or basically anything else. Black bears just don't care about your period problems, apparently. The bears tested with tampons soaked with beef fat found that pretty awesome, but ignored all other tampons.
The authors suggest that black bears may care less about menstrual blood than polar bears because black bears are more omnivorous. Given that polar bears eat exclusively meat, they may be less picky, but the authors also note that several of the bears tested had recently eaten young deer. I do have to wonder, if polar bears were tested again, if they might be just after the blood, regardless of where it came from. It could also be that none of the black bears were all that hungry, food was pretty abundant.
Obviously there are plenty of issues with this paper. There was only one comparison to blank tampons OR non-menstrual blood. There was only one comparison for a woman not on her period. There were no comparisons with men (I mean, at some times, wouldn't taint odor be plenty bad too??). The bears weren't hungry, and usually had other bear things to do. What's clear is that menstrual blood is not exactly a preferential food for black bears. So unless you're out and around some seriously hungry bears, the woods are relatively safe.
Rogers, L., Wilker, G., & Scott, S. (1991). Reactions of Black Bears to Human Menstrual Odors The Journal of Wildlife Management, 55 (4) DOI: 10.2307/3809511