Bear and Bird Feeder Combo!

When I had an email show up in my in-box with these photographs, I was not convinced. Especially only two days after April fools day. I did some research, which yielded some very big surprises. I've kept the biggest for last.

Obviously the first question that comes to mind is: Is this real?! In these days, easy access to PhotoShop and other graphical editing tools has somewhat rightfully turned us into skeptics. So let's investigate!


Wow! So it is possible that my entire analysis was incorrect! I recently recieved this email from someone named Amy:

I found your website about the bear and the bird feeder work that you did and that you think that they are fake pictures. I must say that they are in fact real pictures taken by a friend of my parents they were taken here in Juneau, Alaska. They were not altered or any thing. Yes it is possible for a bear to scale a rope just as it is possible for a bear to walk along the top of a chainlink fence.
Then, later:
I am assuming that someone took the pictures from the original email and used photoshop to get rid of the lady's head that was there. So the use of Photoshop would have been used so that someone could claim that they took the pictures when they really didn't. I did see that a lodge owner from the lower 48 claims that they took the pictures but since I can drive to the lady's house here in Juneau, Alaska I know that it is not true. I suggest that if you really want to see if this is true to come see our bears here in Alaska in action.

The Photos

bear in tree attempting to get bird-feeder
Figure 1. The bear has climbed into the tree.

bear in tree attempting to get bird-feeder
Figure 2. The bear is climbing over to the feeder.

bear in tree attempting to get bird-feeder
Figure 3. The bear has the feeder in its mouth.

bear that snatched a bird-feeder
Figure 4. The bear is on top of the feeder

Is it real?

First, a quick google search reveals that we are not the only skeptics. The website "Museum of Hoaxes" apparently also had this land in their in-box. See here. This is as good a place as any to launch into our analysis. Go ahead and check it out.

Somewhat ironically, probably the first thing you did NOT notice is that at the top of the page in tiny font is the following. Status: Real. End of discussion? The first thing you probably noticed is the reasons in support of this photo. Specifically: The New Hampshire Fish and Game Department even has instructions on their website titled "Don't Let your Bird Feeder Become a Bear Feeder!" One of their recommendations is to "stop all bird feeding by April 1, or as soon as snow melts"

But that's weak support. And what about the ensuring wild debate? Here are some of the comments both for and against these pictures.

Fact Checking and Analysis

Would The Rope Break?

Enter Sandman the Engineer. So can the rope take it? Well, this is actually a pretty straight-forward problem, but we'll have to make some assumptions.

Specifically, we need to have a good guess for:
  1. The rope's thickness
  2. The rope's material
  3. The bear's weight (sorry bear!)

So one of the comments was that "3/16 plastic rope" can support 1,300 pounds. Well, google doesn't have much to say about "plastic rope", so let's assume it is nylon. Nylon has an ultimate stress of 10.9 ksi, however, it's important to note that the rope will start yielding well before that! We will stick with the ultimate stress to give every benefit of the doubt.

How much stress can 3/16" nylon rope support? Turns out no more than 300 lbs. If the poster actually meant 3/8", the maximum supportable force would jump to 1,200lbs which is reasonably close to the author of the post's statement. But what if the rope were as thick as half an inch? This would yield a maximum supportable load of 2,135 pounds, or a little over a ton. We'll give it to them. Benefit of the doubt.

How much can a black bear weigh? Wikipedia claims that female black bears can get up to 400 pounds and males up to 500 pounds. Does this make Wikipedia racist and sexist? No really, so now we know that the post's author gave very conservative numbers for his case.

So we are done. Aren't we?

In this bear scenario I think it matters what the rope is anchored to. Sort of like a fishing pole: the fact that it bends allows you to land a fish that may be substantially heavier than the rating of the fishing line.

Someone needs to revisit high school physics. I mean--let's test this hypothesis. In all fairness, it was very astute that someone picked up that the bending in the rope would play a major role. Too bad the first guy didn't notice this...

Free-body diagram of bear on rope
Figure 5. A free-body diagram showing the forces of the system.

Look at the shape of the rope in figure 4 next to the free-body diagram in figure 5. This is a very common high school physics question: what are the tensile stresses in the rope? Assume the bear weighs 500 pounds. Assume θ = 40° (a highly conservative visual estimate from Figure 4). Also, assume that the rope snaps suddenly at the ultimate stress and does not yield. Then assume "quasi-static equilibrium--the bear moves incredibly slowly (a.k.a 'sloth') and is extremely careful not to bounce (thereby creating dynamic loading).

T1 = T2 cos(θ)
T2 sin(θ) = 500 (lbs)

T1 = 596 lbs
T2 = 778 lbs

In fact, if we make the assumption that the rope is a hefty half inch thick, it will (by our previous assumptions) hold the bear as long as θ > 13.5°, which it clearly is.

So, benefit of the doubt, it is conceivably mechanically possible that a bear could do this. Now does their autonomy allow for a bear to grab a rope (they have paws, not hands) as is shown in figures 2, 3, and 4? I'd really like to, as I've been unable to find out.

The Gray Stuff

I googled "squirrel cone" and had 70 results. None of them seem to refer to this Acme Anti-Squirrel material. I have to concede that it could just be plastic that is visible only from certain angles through the trees.

Photo was taken by a Friend of a Friend of a Coworker of [Museum of Hoaxes User Blondin]'s Daughter

Ohhhhh! You must mean Willie! That explains it.

These pictures were taken by a friend of a friend of a coworker of my daughters in Sudbury, Ontario (I'm not making this up).

Last summer my daughter worked for the Ontario Ministry of Natural Resources (or as we like to call them the Ministry of No Results) and someone in their Sudbury office emailed these photos with a note that a friend had taken them in their back yard.

No, but (once again), benefit of the doubt. This is well explained by Six Degrees of Separation. Chances are you really do know the person who originally perpetrated this hoax took this very authentic photograph. Skeptics would rightly point out that just because the photos showed up at the Ontario Ministry of Natural Resources (or gullible Canadians, as I'd like to call them), doesn't add any authenticity since anyone can send an email to any government body of their choosing.

April 1st

The New Hampshire Fish and Game Department even has instructions on their website titled "Don't Let your Bird Feeder Become a Bear Feeder!" Their recommendations include: "Stop all bird feeding by April 1, or as soon as snow melts;" and, "Clean up any spilled birdseed and dispose of it in the trash."

I admit, it is a little suspicious. Ironically, I received this email April 3, 2007 which raised the early warning flags. Someone emailed out a whole bunch of April fools jokes and now they are spreading virus-like around the Internet. Possible.

Now the website I am referring to received this email way back on March 23, 2006. It's been over a year--at least. Probably more, since it generally takes time for this sort of stuff to propagate.

Everyone is a Gullible Moron & Numerous Touch Up Errors

First, not nice to call names. Second, I took a pixel-by-pixel view all I can say is if the image was edited, it was done very carefully or with a high-end graphics program such as The GNU Image Manipulation Program(GIMP) or PhotoShop.

Enter Hacker

People are funny sometimes. Often in a quite sloppy way. Halfway into my investigation (and I admit a quarter done with this web page) I decided to let the burning hacker inside have a whack. And you wont believe what he found!

Adobe Photoshop Elements 2.0
2005:08:06 15:02:10

Sneaking around through the actual image showed that this image was last edited August 8, 2005 at 3:02pm with Adobe Photoshop Elements 2.0, likely pirated. Ah-hah! This hoax has been BUSTED!

Perhaps the original perpetrator was simply trying to remove some of the bear's red-eye or whiten a toothy smile, but for whatever reason, these images have been edited. Although we found that much of the arguments against the authenticity of these photos had to be put aside, under the aegis of "benefit of the doubt", we can now safely repeal this and sleep soundly with the knowledge that these pictures are FAKE.

Fin. Q.E.D. (quo errat demonstrator | quod ego dico)

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