Monday, June 15, 2015

A Summer of Secrets

Posted by Kirk Mona



Summer is here and it is time to launch the Secrets of Summer video series. If you are reading via email. Check out this link: https://www.youtube.com/watch?v=wwKJ5GfyvXA



I'll be bringing you a series of videos all summer long debunking the top nature myths I encounter in my job as a professional naturalist. Be sure to subscribe on YouTube to see them all.



~Kirk
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Friday, June 5, 2015

Watch out for White-crowned Sparrows

Posted by Kirk Mona
As the white-throated sparrows move through in the spring keep your eyes open. All may not be as it seems.

Here in the Twin Cities and in countless other areas, we get thousands upon thousands of white-throated sparrows migrating through in the spring as they head north. They don't stick around long but their distinctive white throat and "Oh Sweet Canada, Canada, Canada" call are a much welcome sign of spring. 

Seeing the first one each year is a treat but keep looking, you might be missing out if you start to ignore them. Mixed into flocks of white-throated sparrows will often be a white-crowned sparrow.
 

White-crowned sparrows belong to the genus Zonotrichia along with the White-throated, Golden-crowned, Fox and Harris's sparrows.

At a quick glance it is easy to dismiss these beautiful birds for yet another white-throated sparrow so keep your eyes open. They often hang out in flocks with white-throats sparrows so you need to look carefully.

White-crowned sparrows are found in the from mid-Iowa south in the winter and in some places out west year-round but are only in Minnesota during migration. They will soon leave for the very northernmost parts of Canada to breed. Get out there and enjoy them while you can.

~Kirk
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Sunday, March 15, 2015

Warm Weather is a Disaster for Maple Syrup Season

Posted by Kirk Mona
There's no denying this unseasonably warm weather feels great but not all is sunshine and gumdrops. The rapid switch to all warm all the time means it is not dipping below freezing at night. This spells disaster for the maple sap run.

Maple trees will not run if the temperature does not dip below freezing at night. Last year at work we collected 700 gallons of sap by the end of the season. Right now we have maybe 30 and unless it rest cold again fast the season may be over. WCCO news came out the the nature center to do a report about the poor season. Their embedded player doesn't actually work so I'm afraid I have to go old school and offer you this link to their site.

http://minnesota.cbslocal.com/video/11227151-spring-like-temps-cutting-maple-syrup-season-short/
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Monday, February 2, 2015

Official 2015 Twin Cities Groundhog's Day Report

Posted by Kirk Mona
The 2015 Report:

What a difference a year makes!


On Groundhog's Day 2014 we'd just pulled though yet another "Polar Vortex" and there were high snowdrifts everywhere. Here we are today and solid snow cover is hard to find anywhere in the Twin Cities.

Last year I took a new job at Lowry Nature Center in the west metro after a 12 year stint at Warner Nature Center in the east metro. This means that last year I missed out on seeing my old pal "Stuff Stanley" the groundhog of record for many of the Official Twin Cities Groundhog reports over the years. I decided this year to pay an early morning visit to Stanley to see if he saw his shadow. Did he? You'll have to watch the video to find out!






The official Twin Cities Groundhog Prediction:
Just like last year, the groundhog DID see his shadow in the Twin Cities so we have six more weeks of winter to look forward to. That's the story anyhow. Last year we had a huge warm-up right after Groundhog's day that saw us flirting with 50 degrees before plunging down again at the end of the month. This year could be a bit of the same. While the forecast calls for a few days near zero this week the longer range forecasts are looking at us going up near 40 degrees again. 


Personally I'm going to have to predict against the groundhog this year. We have very little snowfall and a warm spell in the 40s could melt what we do have away. Once the ground is exposed, the longer days and more direct sunlight we're getting are going to help warm up the ground and create  more warm days than cold days all things being the same. 

That's my personal prediction, we'll see who's right, me or a stuffed groundhog.

Background: 

What's the connection between Groundhogs, shadows and the seasons?

The connection is tenuous at best. Further south than Minnesota, male groundhogs do come out of hibernation early to scope out and check on their breeding territory. In Minnesota, February 2nd is usually too early for this to happen. Seeing the first groundhogs checking out their territory is surely a sign of spring though. Okay, but what does seeing a shadow have to do with it? The connection to shadows has to do with prevailing weather patterns. We often associate sunny days with warmth and the coming spring but sunny days in the winter aren't always warm. Clear winter days are often the result of cold Canadian air that has settled over the state. A shadow in the winter often means we're in a pattern of cold air flowing south. It can take many weeks to break that pattern and warm the area. All of the snow we have will also keep us cold longer.

Celestially, February 2nd is an important day. According to the solar calendar, it should mark the end of winter and the beginning of spring.

Forty-two days ago was the winter solstice, the day of the year when we have the least sunlight. From that day on, the amount of daylight increases until the day when there are equal amounts of night and day. We call this day the equinox and it falls around March 21st. February 2nd falls half way between the solstice and the equinox so in theory it should mark the end of winter and the beginning of spring.

Has anyone seen any crocus flowers blooming?

Obviously the winter solstice is not really mid-winter. Why do we call the solstice mid-winter if it is really more like the day winter begins? This has long been a puzzle and even caused a few arguments between astronomers and meteorologists. The answer is something we call the lag of the seasons and it affects Groundhog’s day as well. Yes, it is true that Groundhog’s day technically marks the beginning of spring from a celestial point of view but our experience tells us otherwise. Our seasons lag behind what the sun tells us in the sky.

Saying spring starts on Groundhog’s day is a little like saying a frozen dinner is ready to eat as soon as it is pulled out of the freezer. The northern hemisphere has been cooling down for months by the time the solstice arrives. Forty-two days with just less than a minute more sunlight each day is not enough to thaw out the frozen landscape into a lush vernal garden.

The established pattern of cold weather continues for many weeks after the beginning of the increase in daylight. This lag makes it seem like mid-winter actually falls on Groundhog’s day rather than the solstice. Rest assured though that on Groundhog’s day, even if it feels like the middle of winter, we are getting an hour and seven minutes more daylight today than we did just forty-two days earlier.

Groundhog’s Day may marks the beginning of spring according to the sun but it will be about forty-two more days until we feel the change enough to call it spring. It may seem like winter has a grip on the land but the sun has been working hard to reverse the trend for over a month and we’ll soon start to see those effects.

Incidentally, the legend tells us that if the groundhog sees its shadow it will be scared back into the den and we’ll have six more weeks of winter. Why six weeks? How many days are there in six weeks? Forty-two. Six weeks takes us exactly to the spring equinox.
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Friday, January 30, 2015

Can you guess what this is?

Posted by Kirk Mona

Image: Erbe, Pooley: USDA, ARS, EMU

This image showed up in my news feed this week. Can you guess what it is? My initial thought is that it appears to be rather crudely made of plaster. A bad sculpt of a tie fighter perhaps? The truth is far stranger. 

Keen eyed observers may note the white scale bar and label in the lower left hand corner. This object is only about 600  µm across. That's 600 micrometers or about half a millimeter. The image was taken with an electron microscope and is magnified 50,000 times. 

This is an object every reader has seen, most have touched and many have eaten though you should take care to avoid colored versions. 

This is a snowflake. 

Perhaps "flake" is a bit of a misnomer. Falling snow comes in several varieties. As we often teach school kids in my job, snow comes in stellar dendrites (those are the ones you usually think of) as well as needles, columns and more. 

The odd snowflake in the photo is a peculiar variety of capped column. I recognized it right away as we have a cardboard capped column on display at work right now. 



The bumps on the side are rime ice that formed on the surface. I find it fascinating that the columnar snow structure the rime ice is growing on is so imperfect. I think we get this impression that snowflakes, essentially just crystals of water should be more perfect. Of course, almost no crystals in nature are ever perfect. I blame Snowflake Bentley. 



Wilson Bentley is in part responsible for our distorted image that all snowflakes are perfect and beautiful. He was one of the first to capture snowflakes on film and they showed for the first time via amazing detail that snowflakes were highly complex and beautiful. Let's be clear though, Mr. Bentley knew that many if not most of the snowflakes that fall are not perfect. He had to sift though many poorly formed snowflakes to find the truly spectacular ones. He looked at so many he knew they were not all perfect. The public only saw the most beautiful ones and since they were the only ones we had seen it distorted our perception of them. 

The close up photo of the capped column snowflake at the top of the page is beautiful as well but not because of the perfection it displays. It is beautiful because it is imperfect, strange and fills us with wonder. 


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Wednesday, January 21, 2015

Petrichor explained

Posted by Kirk Mona
If you're a doctor who fan like I am you know the word Petrichor. Author Neil Gaiman snuck the word into the episode The Doctor's Wife. The word was part of a telepathic passcode to open the hidden backup control room in the TARDIS. "Oh course," you say. "We are nerds, we know this!" You may also remember that Idris defined it as "the smell of dust after rain."

The word wasn't a fabrication of Gaiman, it was coined in 1964 by Australian researchers Bear and Thomas in the journal Nature. The posited that an oil extruded by plants in dry periods is somehow put into the air by the rain. The oil actually helps prevent other plants from germinating and thus helps the plants avoid competition. I would think this would also prevent their own seeds from germinating but perhaps that is discussed deeper in the research. To be fair to rain smells, Geosmin is also responsible for the smell of the earth after rain but until Gaiman works that into a Doctor Who episode I'm afraid that word will also remain obscure.

Deeply nerdy and linguistically savvy Doctor Who fans and biologists alike were excited when researchers from MIT recently presented evidence on how the compounds that comprise petrichor get into the air. They dropped raindrops on 28 different soil types hundreds of times and filmed the results with high speed cameras. You can see tiny particles become aerosolized and swept up in air currents as the result of the drops. The high speed footage has been released online and it is fascinating to see the particles launched into the air. It is fun to think of hundreds of trillions of raindrops hitting the earth in a storm, each releasing tiny particles into the air that we smell as fresh petrichor.




(If you are viewing this via email you will not be able to see the embedded video. Click here to view online.
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Tuesday, January 20, 2015

Snowy Owls Across the Northland

Posted by Kirk Mona
Once again snowy owls are being seen across the north land. 2014–2015 is turning out to be a pretty good season if you want to see a snowy owl. There probably have not been as many owls seen as were last winter, however, there still good opportunities to get out and see one of these magnificent birds if you're interested.

Mike Hendrickson has complied a map showing all reported locations of Snowy Owls here in the capital of the North. 

You can also get up to the minute information by running a species report in eBird

Snowy owls seem to end up in some interesting places. Many of them do not seem particularly concerned about humans. One of the more popular and easily seen snowy owls around the Twin Cities has been hanging out at the Shoppes of Arbor Lakes shopping area in Maple Grove. The owl alternates sitting on top of the potbelly Sandwich shop, the AMC movie theater, and a beauty supply store. It may not be the most glamorous place to see if they snowy owl but it is certainly an easy place to see one. The photo at the top of this post is likely an immature female snowy owl and this is the one currently being seen at Arbor Lakes.

Good luck, be safe, be respectful and enjoy the birds.
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