Journal Entry

Arctic Ground Squirrel Hibernation

Lots to Learn

Wow. I am learning so much at the PolarTREC Orientation and Share Fair. Much of it is about how to use the technology and load information to the PolarTREC website so that we can tell the stories behind the science. Yesterday afternoon we took a field trip to the Museum of the North and enjoyed a presentation by PolarTREC researcher Jeanette Moore of the University of Alaska, Fairbanks on arctic ground squirrel hibernation. She hosted a teacher, Alicia Gillean last year and Andre Wille from our group will join her this year at Toolik Field Station in north Alaska.

Jeanette Moore and Arctic Ground SquirrelJeanette Moore of the University of Alaska, Fairbanks tells us about the amazing abilities of these remarkable squirrels. Mrs. McNeal with an arctic tree squirrelThe squirrel was so cute! He was making a few movements while I held him. Waking up?

Arctic Ground Squirrels get REALLY Cold

Scientists are interested in studying arctic ground squirrels' ability to survive extreme temperatures. While hibernating approximately seven months a year, a squirrel's body temperature can lower to -2º C , they have no electrical stimulation in their brain and their metabolism slows down to practically nothing. In other words, if this was you, you would be very dead! And yet, these cute little squirrels recover, wake up and go on with their busy lives.

Hibernating Arctic Tree SquirrelWhile hibernating, the squirrels curl into a little ball and cover their face with their tail.

Why Do Scientists Study Squirrels?

Understanding how the squirrels do this is the subject of the research. Scientists use advanced genetic analysis to analyze which genes are regulated at different stages of hibernation. The results could have important biomedical implications for modeling cerebral ischemia (reduced blood flow to the brain), traumatic head injury and hypothermia.

Arctic Ground SquirrelArctic Ground Squirrel. Photo by Alicia Gillean (PolarTREC 2013), Courtesy of ARCUS

Now This Sounds Like Fun!

While at Toolik Field Station, Alicia and Andre help trap the ground squirrels and insert a "logger" in their abdomen. The logger is about the size of a fat dime and records the internal temperature of the squirrel. Inserting the logger takes a bit of mini squirrel surgery. Don't worry! The squirrel is anesthetized and doesn't feel a thing. Next, each squirrel is ear tagged for identification and then they are released back to the wild. Later the squirrels are trapped again so that the loggers can be recovered. The squirrels are stitched back up and let go. The scientists then read the data from the logger.

Alicia Gillean ear tagging a squirrelKate Wilsterman attaches an ear tag to an anesthetized Arctic ground squirrel. Toolik Field Station, Alaska.Photo by Alicia Gillean (PolarTREC 2013), Courtesy of ARCUS

WHAT?!?!?

Now that's some pretty cool science! What questions do you have about arctic ground squirrels? Post them in the comments section and will I will try and find the answer. Or, check out this guy, Matsutaka Uchikoshi, who hibernated for three weeks after he went missing in a remote mountainous region of Japan: http://usatoday30.usatoday.com/weather/news/2006-12-20-japan-hibernation_x.htm
What?!?

Matsutaka UchikoshiCan humans hibernate? AFP/AFP/Getty Images

Comments

Fri, 04/25/2014 - 14:26

Guest

If the squirrel woke up would it say awake or go back into hibernation?
-Will Tomlinson & Noah LaFata
per.7

Sat, 04/26/2014 - 11:56

Peggy McNeal

Will and Noah,During hibernation, every two to three weeks the squirrel shivers itself
back to its normal temperature which it maintains for 12 to 15 hours
before going back into popsicle mode. So to answer your question, if it
woke up, it would go back into hibernation unless it was coming out of
hibernation for the season.

Tue, 02/18/2014 - 16:25

Guest

When they get the data do they have to try to catch the same squirrel and keep setting a trap out for them to catch the right one by Brian s.

Sat, 04/26/2014 - 12:12

Peggy McNeal

Rachel and Noah,Well presumably, if he was hibernating his metabolism slowed down and so does his need for water. Animals don't need water when they hibernate. His biological needs during hibernation change. It's like he's in suspended animation. It is totally weird, huh?

Mon, 04/28/2014 - 04:11

Peggy McNeal

Keith and Matt,When I was in Fairbanks, I got to see and hold hibernating arctic ground squirrels that were kept in a lab. After about 20 minutes of handling, the squirrels were starting to show signs of waking up so we put them back into their cold, lab burrow. So with enough stimulation they would wake up, but their natural hibernation spot is in a burrow underground so I wouldn't think it is particularly noisy down there.
Hibernation is a state of metabolic depression and some species have evolved the ability to do this. All of their body functions slow down so the requirements for oxygen, warmth, and nutrition are much below normal active levels and they are able to endure this state. It is a survival mechanism to conserve energy during a time when inadequate food is present.

Tue, 02/18/2014 - 17:33

Guest

If the blood turns to a slush like you said isn't that cold enough for the blood to build up in a vessel and clog it which would prevent blood flow killing it? -Cameron To

Tue, 02/18/2014 - 18:05

Guest

Is it possible for the blood to freeze before their body heat spikes back up?
Jake C. period 6

Thu, 02/13/2014 - 07:40

Guest

The 5 months they aren't hibernating, what do they do? Do they just load up on food for the upcoming hibernation? Or do they catch up on the food they missed during the previous hibernation?

Tue, 02/18/2014 - 18:10

Peggy McNeal

Hi David,By figuring out how the arctic ground squirrel's brain recuperates from deep hibernation, the scientists are hoping to figure out new ways to reverse cell damage in diseases that affect the brain, like Alzheimer's disease. Alzheimer's disease strikes many older people. It would be great if we could figure out a way to reverse or prevent it. Do you think a little squirrel can help us figure that out?

Tue, 02/18/2014 - 18:15

Peggy McNeal

Hi Cameron,Like all other body functions, circulation slows way down too. (Remember I said the heart rate goes way down?) All of this would speed back up as the squirrel warms, which would also warm up the blood. So when it really gets moving again the blood is warmed up. Isn't that weird? That's a great question that I hadn't thought of yet.

Tue, 02/18/2014 - 18:21

Peggy McNeal

Hi Jake,What you noticed from the graph we made today is that as the hibernacula continued to get colder and colder (down to -16ºC) the squirrel stopped lowering its body temperature at about -1.6ºC. That's as cold as the squirrel gets- probably because any lower and it would die, That temp is below the freezing point of water but not below the freezing point of the squirrel's blood because the blood contains some salts. Remember when we made ice cream we were able to supercool the water (get it below the freezing point of pure water) because we added the rock salt. So no, the blood doesn't freeze. Thanks for the great question!

Tue, 02/18/2014 - 18:32

Peggy McNeal

Great question Brian, I wondered that myself. The squirrels are ear-tagged so they can identify them. And apparently they don't roam far from their burrows, especially the females. So the scientist we spoke to said it's fairly easy to put the traps out again and just catch the same squirrels. Also, they implant the device in many squirrels at a time so if one squirrel goes missing they still have plenty of data.

Thu, 02/13/2014 - 09:54

Peggy McNeal

The five months they aren't hibernating they are partying!!! No, just kidding, well kind of. The males leave their burrows earlier than the
females so they can get their game on. Seriously- there is a lot of
male-male competition for access to the females during this time. Then
females leave their burrows and mating follows. The pups are born 25
days later and weaned after six weeks. After that you are correct, they
eat and eat and eat to prepare for the upcoming winter. Other than
that, they hang out and do their arctic ground squirrel thing. Thanks
for the question!
On 2/13/14 7:40 AM, webmaster@polartrec.com wrote:
>

Thu, 02/13/2014 - 10:27

Guest

What an interesting study, Peggy. I had no idea any mammal could lower their body temperature to such an extreme level as the artic ground squirrel. Makes perfect sense, but almost seems magical. They look adorable. I'm learning a lot!

Thu, 02/13/2014 - 10:39

Peggy McNeal

Isn't it crazy? Jeanette Moore told us that if you could see their blood it would look like a strawberry slurpy. Their metabolism drops so
low that it's as if they really are in a suspended state of living.

Tue, 02/18/2014 - 20:21

Guest

If scientist do find the way how ground squirrels sleep for 9 months straight, how would they make the cure for people with brain damage from ground squirrels?
-Antonio Olivieri Period 6

Tue, 02/18/2014 - 21:06

Guest

Is it possible for the squirrel to completely die during hibernation for some reason?-sarah m period 6

Mon, 04/21/2014 - 14:24

Guest

During hibernation when his metabolism was slowed, does he lose weight from not consuming food?
Chloe Riddlespurger, Seiper Sindi - Period. 7 Mrs. McNeal

Wed, 02/19/2014 - 03:42

Peggy McNeal

Yes, it is Sarah. Arctic ground squirrels can actually freeze to death, die from disease or because they become lunch for another critter. Arctic ground squirrels predators are grizzly bears, hawks, owls, falcons, eagles and ermine. An ermine is a weasel that grows a snow-white coat in winter. They look totally cute until you realize this is one hardcore carnivore, with razor sharp teeth used to take down animals larger than itself. Google it and you'll see!

Wed, 02/19/2014 - 04:02

Peggy McNeal

Antonio, it's not so much that scientists are studying how arctic ground squirrels hibernate, they are more interested in how they recover from such a total brain shutdown. While the arctic ground squirrel hibernates, millions of synapses (connections between brain cells) wilt. So that would be a situation something like a human with brain damage or Alzheimer's disease. And yet in only two hours after emerging from hibernation, the squirrel rejuvenates its brain, compensating for the lost synapses. In fact a newly emerged squirrel has a healthier brain than one found in the middle of summer. When brain cells in the human brain die, that's about it. Our brains seem to have a very limited ability to heal themselves. Scientists aren't sure what triggers the squirrel's brain recovery but think it may have something to do with a protein. If they can figure that out and apply it to humans, maybe someday brain damage can be reversed. Thanks for the thoughtful question, Antonio!

Mon, 04/21/2014 - 14:27

Guest

Hunter Smith Period.7

How dose matsutaka uchikoshis brain contain to be stable while after getting unconscious for three or so weeks. they say he became 100% "ok" after the incident of him tripping and falling into a "coma" like endured sleep when he goes into hibernation. so how do we not know that he just didn't have a coma?

Sat, 03/08/2014 - 15:24

Guest

Where did the researchers find the artic ground squirrels?
How did the researchers keep the squirrels in hibernation after they caught them?

Tue, 04/29/2014 - 14:04

Guest

this is marty beck from 7th period i was wondering if the squreels woke up from hibernation early would they die if so why.

Tue, 04/29/2014 - 14:08

Guest

Hi Mrs. Mcneal, so while the squirrels are sleeping if they were woken up before the end of their hibernation, would they become mentally or physically damaged like a sleepwalker would if they were woken up? Thank you! -Brooke S. and Cameron T. from 7th period

Tue, 04/29/2014 - 14:12

Guest

If that Japanese guy actually did hibernate does that that mean that humans have similar brain properties. Jonathan ingles period 7

Tue, 04/29/2014 - 14:14

Guest

How did Matsutake Uchikoshi go without food, water, and not going to the bathroom for 24 days, and just wake up like hardly anything happened? period 7
Skylar & Christain

Tue, 04/29/2014 - 14:18

Guest

how was he able to recover 100% after every one of his organs failed?

Tue, 04/29/2014 - 14:19

Guest

the one above was me sorry,
endiya

Tue, 04/29/2014 - 14:23

Guest

could an artic ground squriel day in the frozen toundra

Tue, 04/29/2014 - 14:26

Guest

This is Ryan and Angelica from per. 7. How much do the squirrels eat when they wake up from hibernation?

Wed, 04/30/2014 - 17:12

Peggy McNeal

Ryan and Angelica,The squirrels basically eat non-stop when they are not hibernating. So that eat and eat and eat and eat. That's their job when they aren't hibernating. A lot of eating.

Thu, 05/01/2014 - 03:42

Peggy McNeal

I assume you are talking about Mitsutaka Uchikoshi? His organs didn't fail. His organs slowed and his brain was protected. It is not completely understood how he survived this, which is what makes it so fascinating!

Wed, 03/12/2014 - 03:52

Peggy McNeal

They trap the arctic ground squirrels in the tundra outside the research station. They just use wire cage traps and carrots for bait. Sometimes they trap the same squirrels year after year. The squirrels fall for the carrot trick every time.
They have a few in the lab to study year round. They hold them in hibernation by keeping them at very cold temperatures, like in a freezer. The one that I saw was transported to our classroom in a cooler- just like one you would use to carry food to a picnic.

Thu, 05/01/2014 - 03:42

Peggy McNeal

Skylar and Christian,Well if you aren't taking in food and water then you don't need to go to the bathroom either, right? He didn't just wake up like hardly anything happened. Uchikoshi was treated for severe hypothermia, multiple organ failure and blood loss from his fall. It isn't understood how he did this which is what makes it so fascinating!

Thu, 05/01/2014 - 03:42

Peggy McNeal

Jonathen,That is the thought. Hey! You just asked a great question that could be the starting point for new investigation and experimentation! :)

Tue, 03/24/2015 - 19:08

Timothy Benton

I wonder if humans brains could be repaired after being damaged by strokes

Thu, 05/01/2014 - 03:42

Peggy McNeal

Brooke and Cameron,I don't think so. If given the chance they would just go back into hibernation. The idea that waking a sleepwalker could cause their death or other damage is a myth.

Thu, 05/01/2014 - 03:42

Peggy McNeal

Marty,No. They would most likely just go back into hibernation.

Thu, 04/24/2014 - 08:11

Peggy McNeal

Chloe and Sieper,Yes.  The squirrel loses about one third of its body weight.  Can you even imagine?  Great question!

Thu, 04/24/2014 - 08:26

Peggy McNeal

Hunter,This type of state is called "suspended animation"- the slowing of life process by external means, in this case by extreme cold.  It is similar to a coma.  I think the difference is what causes it.  I also don't think that it is completely understood what happened to him, but it sure is weird.  Thanks for the question.

Tue, 05/06/2014 - 13:01

Guest

since humans and animals are both mammals why cant we find a way to hibernate like the ground squrriels?.

Tue, 05/06/2014 - 13:01

Guest

since humans and animals are both mammals why cant we find a way to hibernate like the ground squrriels?.

Wed, 05/07/2014 - 03:23

Peggy McNeal

since humans and animals are both mammals why cant we find a way to hibernate like the ground squrriels?. 
We have adapted to different environments. The many species of mammals have evolved to a variety of environments and are different even though we share characteristics as mammals. We also can't pick things up with our trunks, hang by our tails or use our teeth to dig tunnels underground. Most mammals don't hibernate. Humans evolved on the African savannah where there was no need to endure a long cold season. Could we find a way after learning from this research? After all, it seems kind of like a coma and humans survive comas (although often with brain damage)? Perhaps, but I doubt it. We are good at other things. Like being highly intelligent.

Wed, 02/12/2014 - 10:44

Michelle Brown

What a great journal Peggy! I love the pictures and am impressed at how much you picked up from the presentation and the great pictures you found of the (safe) surgeries done on the squirrels. Thank you for such a great journal!

Mon, 02/17/2014 - 12:02

Guest

If you dropped it or something could it wake up?

Mon, 02/17/2014 - 21:00

Peggy McNeal

Yes, in fact while we were holding it, it even started to wake up a bit just from the warmth of our hands and the warm room. What's interesting is that during its 7 month hibernation, it actually shivers itself back to normal temperatures every two to three weeks for 12 to 18 hours before going back into its deep freeze. Isn't that weird? Apparently it's to prevent the brain from withering away and dying.

Tue, 02/18/2014 - 14:24

Guest

How would it help humans to know which genes make them live while acting dead?~david coffey p.3

Fri, 04/25/2014 - 14:23

Guest

How would Matsutaka Uchikoshi be able to survive without water because a human body can only survive three days without water?- Rachel S. & Noah M. from 7th period