Wow: 13-lined ground squirrels endures winter by packing fat *into* heart

Denver 2009 - Thirteen-Lined Ground Squirrel 01

A thirteen-lined ground squirrel going on a fat binge. Photo

The editorial staff of Squirrels, Squirrels, Squirrels has visited Minnesota in December. So, we’re only partially surprised to read the findings of a cool study out of Duluth, which examines how the 13-lined ground squirrel hibernates without becoming a completely frozen solid squirrel-sicle.

(I mean, these cute critters of course have fur and can huddle together in their little hidey-holes, but still, when it’s -40 outside, …it seems like only White Walkers should be alive and in the mood for napping, while everyone else gets on an RV and heads to South Padre Island.)

Anyway, how do they do it? It takes extreme metabolism to counter the extreme weather. Precisely, they literally store fat in their hearts, and then slowly burn off that fat all winter long. Yes, it sounds counter-intuitive to long-term survival (equivalent to a human eating a triple-bacon cheeseburger for every meal), but the long starvation following their autumn pig-out creates a metabolic state known as “ketosis,” and that apparently brings them good tidings, cheer and above-average longevity compared to similar non-hibernating species.

Lest you wonder why the hell anyone cares, Katharine Gammon, writing in Chemical & Engineering News, clears that right up for you:

“Eventually, this knowledge may help researchers develop ways to protect heart tissue from the harmful effects of free radicals that are produced after a heart attack.”

So there. Squirrel research saving lives.

Botany bulletin: So apparently oak trees go nutty every few years, and 2015 is one of them

A squirrel enjoying a masting?   Photo by Hills_Alive

The Albany Times-Union has an excellent write-up on the far-reaching ramifications of a masting, the awkward botanical term for a regional over-supply of acorns. Apparently, 2015 is a “masting” for the oak trees of the Northeast. (It does seem this way in my little corner of Queens, where walking under the gargantuan, smog-fed oak trees can leave one a little fearful of an acorn-related skull fracture.)

Why 2015? It seems to be related to optimal weather conditions, and the necessity is driven by survival: Acorns are so appealing to wildlife that oak trees have to over-compensate to guarantee a few won’t get eaten by critters.

“…Acorns are so tasty, such a nutritious food resource, so many animals like them, that if they produce a few every year every single one of them would be eaten up,” a biologist said.

And, at first this all sounds like a net positive: More acorns + more squirrels + more oak trees  = more fodder for Squirrels, Squirrels, Squirrels.

But alas! There’s a dark side. We’ll not give away the spoiler, because the newspaper did all the hard work and we’re a firm believer in giving credit where credit is due. So check it out for yourself: This year’s acorn cascade has hidden impact

And, in celebration of the masting, here’s some gorgeous pictures celebrating all things acorny.

A woodpecker prepping for the apocalypse:
Acorn Woodpecker m.

Still life with acorns:
Fresh acorns

Convincing proof that the universe is just one giant, ever-expanding acorn:
Quercus rubrum, acorn cap, ontario_2014-08-08-10.51.08 ZS PMax

The perfect cake for sending to the authors of SqSqSq:bûche de noël - oak leaves & acorns

Where Have All the Acorns Gone?

I’m a little late in posting this, but the Washington Post asks: What’s up with no acorns this year? Even the squirrels are unhappy:

“The idea seemed too crazy to Rod Simmons, a measured, careful field botanist. Naturalists in Arlington County couldn’t find any acorns. None. No hickory nuts, either. Then he went out to look for himself. He came up with nothing. Nothing crunched underfoot. Nothing hit him on the head.

Then calls started coming in about crazy squirrels. Starving, skinny squirrels eating garbage, inhaling bird feed, greedily demolishing pumpkins. Squirrels boldly scampering into the road. And a lot more calls about squirrel roadkill.”

Read the article to find out just what the heck is going on with the Season of No Acorns!

If Acorns Are Poisonous, Why Do Squirrels Eat Them Like I Eat Cupcakes?

Good question, right?

According to Aiken-Standard columnist Bill Hayes, it’s complicated. He wasn’t sure himself so he did a lot of research, such as:

“I found all sorts of stories about Native Americans eating acorns as part of their daily diet. I also found one article that said that the average life span of the American Indian was 30 years but made no reference to acorns as being part of the problem. Because of the high tannin content in red acorns the bitterness was probably strong enough to discourage all but the very hungry.”

As it turns out, some acorns — but not all — are poisonous. And a little biological mechanism at work known as adaptation helps our squirrel friends eat most acorns without any problems.

Read Bill’s column to find out what that adaptation is, and which acorns should stay out of your daily recommended allowance.

More Acorns Means More Squirrels

(Mmmm… Acorns!, originally uploaded by shesnuckinfuts.)

Quick fact: The amount of urban wildlife you see each year is often dependent on how well your trees are doing. Specifically, the more acorns that oaks can produce, the more your squirrels can reproduce, too.

Random anecdote: One year I noticed a disturbing amount of dead squirrels lining the roadways in Westchester County, NY. Every few feet there was a dead squirrel, its fluffy little tail still waving in the wind.

I was a newspaper reporter, and so I used that as an excuse to do a little investigating and call people who would know what was up. Turns out that the previous year was a very good year for acorn production, which meant there was roughly double the amount of young squirrels. Frenzied to collect food for the coming winter, these juveniles were running about, rashly crossing roadways, ending up as roadkill.

As the state biologist told me, it had a way of bringing the squirrel numbers back down to normal, albeit in a particularly gruesome way. I haven’t quite seen the same phenomena since, because I got a job in Manhattan, where squirrels are far more savvy to human dangers, like cars.

For more on the connection between acorns and wildlife, read Acorns vital to natural balance.