Wednesday, January 30, 2013

Crow Roost Video

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What: This is a follow up on the posting from over the weekend. Zac caught a couple of shots of the roost when it was over by the cemetery on Archibald about 3 weeks ago. The rest I took last Friday while hunting them down. On the previous post, I included a map that you can use to see where we were for the different shots.

Ecological notes: The crows are still jumpy in selecting their nightly roosts and it's been hard to keep track of where exactly they are each evening, but they seem to be preferring the Intervale for one of their last staging areas before flying south to their nightly roost. It's an exciting safari everytime I try and follow them in the evenings.

Lots of speculation here, but it seems the main reasons for roosting behavior in crows seem to be:
  • predator avoidance
  • huddling for warmth
  • flirtation (finding mates for the nesting season)
  • storytelling
  • being social
Where: Burlington (and other urban areas)

Tuesday, January 29, 2013

Wonders of the Modern World of Latham Ct


What: Jon and I went for a great walk through Centennial Woods last night - the orange glow of Burlington was bouncing between the low clouds and the fresh blanket of snow, giving the woods an eerie lightness to it. On our way back home we passed by the giant spruce tree in "the extension," which was backlit by an orange glow to the north (right in photo) from the older sodium vapor street lights and the white glow to the south (left) from the new LED street lights on East Ave (something that Chicago's started doing a couple years ago).

Callan and I dubbed the tree one of the wonders of the modern world of Latham Ct. As with some of the other photos I've taken that seem to capture the spirit of the moment, I go back and forth wanting to describe the ecological reasons behind the photo and wanting to pause and inhale the poetics of such profound presence.

Monday, January 28, 2013

Full moon


I wanted to post a quick note about the moon since it was out in such dramatic form tonight, and I was feeling really grateful for all the cold weather that seems to have helped cleared the air, and made everything feel a little more alive in a weird way.

I know the full moon was Saturday night, but it definitely seemed fuller tonight. I had the great fortune of driving due west from about 6pm - 7pm on my way back from Troy and got to watch the moon rise up over the southern part of the lake. In that hour the moon shifted from the deep yellow of a wolf's eye to a striking - almost blinding - white, much like the morning reds, pinks, and oranges giving way to a clear, light blue in the middle of the day (boring explanation: the color shift has to do with the amount of atmosphere between the viewer and the moon - blue gets absorbed first, but giving enough atmosphere longer wavelengths, like red, get absorbed and we are able to see them since they overshadow the blues).  

You can notice the slightest wavy part of the top of the moon, which is actually a shadow, revealing the ever-so-slightest crescent carved out of the moon. The chunk was on the trailing end of the moon's path in the sky, indicating that the moon is waning. And, the photo below is a weird phenomenon -that offset green mirage of the moon - I've noticed a couple of times while photographing full moons.


Sunday, January 27, 2013

Crow Roost


What: Zac and I have been talking a lot about the crows and how they seem to be jumping around a lot from night to night. A couple weeks ago we spotted them at the cemetery on Archibald. Thursday night they were sort of heading that direction so I tried tracking them down. Around 4:30pm on Thursday I watched them flying north from Centennial Woods over the McNeil Plant. Below is a map that shows my route (red) compared to the rough route the crows took.

And I was in Troy, NY for a WFA course this weekend. Saturday night I went for a run as the big full moon was cresting over the hills. It was about 4:45pm or so and I wondered if I might see crows in this neck of the woods flocking to their winter roost. Sure enough I spotted one about 3 minutes into my run flying south over the Hudson River. I followed the crow (which soon disappeared into the flock of hundreds of other crows) for about 3 miles, heading south west from downtown Troy into Watervliet. While I did't get far enough to see the final destination, I saw about 3000 crows in total. These bigger and bigger roosts are an urban phenomenon. In a couple of days I'll post a video of the crows and explain a bit more about why they roost.


View crows in a larger map

Thursday, January 24, 2013

Ice Jams and the Winooski River


What: About a year and a half ago, we were faced with severe flood warnings up and down the state. Irene didn't disappoint and wreaked havoc with both flash floods and sustained flooding events. The day after the storm the air was thick, but quiet, when I went down to the Salmon Hole (just downstream from the dam in downtown Winooski). I took the photos from the bridge on Colchester Ave looking west towards Salmon Hole. They definitely don't really do justice to how absolute and immense the power of that water was.

It's full on winter (Happy coldest day of the year!) and to celebrate I thought I'd head down to the river  to retake photos from the same perspective as I did during Irene. What a difference! Upstream there are a few patches that are open, and there's a frozen waterfall. Somehow we're faced with flood warnings once again; residents in Franklin Co. NY have even been evacuated.

Ecological notes: Ice Jams are not uncommon, and occur on all different scales (you can get an ice jam in a gutter). There are a few types of ice jams, as I'm learning, and the warning is for freeze-up jams. The flood warnings are caused by the excessively cold weather we've had. The cold weather will rapidly freeze the surface water of rivers that haven't frozen over yet (sections of the Winooski, Lamoille, etc.). Surface flow will break off chunks as they freeze and send them downstream. These frozen rafts of ice can get hung up on snags, and any other obstruction. If enough of that ice starts to accumulate it dams up the water. The thicker the ice the better it acts as a dam. If and when those dams burst, they'll release all their water at once, which can cause devastating flooding downstream (as it did in Eagle, Alaska in 2009).  Here's a video from Woodsville, NH of the flooding caused by an ice jam that broke. You can imagine how destructive those chunks of ice would be to trees, houses, etc. along the way.

Where: Salmon Hole @ Winooski River

Monday, January 21, 2013

Orion and why we have a winter sky


What: Following up from a couple weeks back, I wanted to try and draw out in my head (and then on paper) why we have a winter sky. The sketch above is a view looking down on the northern hemisphere of the earth as it rotates around the sun (counterclockwise). The dark part of the earth represents the "nighttime" side of the earth. It might be hard to tell from the drawing but Orion is supposed to be positioned below the earth's axis of rotation around the sun, such that at night it appears to be in the southern portion of our sky.

From our perspective, the sun is fixed relative to Orion (drawn just below the word winter). Earth's position relative to the two celestial bodies changes slight each night and significantly across seasons. The shaded side of the earth (what we call night) always faces away from the sun. So as the earth rotates around the sun, the direction we face out into the universe changes. As we circle around, Orion falls farther and farther away from being in the section of sky framed by the horizon. And pretty soon by the time summer rolls around, the shaded side of the earth faces away from Orion, and all those other winter stars that would appear on the left hand side of the drawing.

All this is comes from pretty basic observations that I'd never stopped to make. Drawing made all the difference for me in figuring out why we have a winter sky. You can also use the above drawing to infer why we have summer in the northern hemisphere when the north pole points towards the sun and winter when it points away from the sun.

Where: Up up up!

Other notes: The full moon is coming up soon and I plan on heading back out to take a couple more photos of the moon at the ball park to get another set of relative photos to gauge how it's arc in the sky has shifted from last month to this month, if at all.

Friday, January 18, 2013

Tree cookies


What: Julia and I had craft night on Wednesday (not different from most nights), and I finally made some good progress on a project I started a few months back. Back in the fall I had gotten a bunch of aspen logs that had been cut along the bike path. I cut it into disks (about 3" diameter) and have been drying it along with sections from beech, white birch, hemlock, and yellow birch. For the disks I wanted to translate photos I've taken into woodburnings of animals that live in and around the beaver pond in Centennial Woods. Last night I made the above disks. I've already finished a chickadee, chipmunk, eastern newt, and mink. I still have the following: great blue heron, honeybees, and wood frog.

Wednesday, January 16, 2013

Red Squirrel Tracks



What: One of my favorite finds of the day on Saturday was a beautiful set of red squirrel tracks that had been preserved on top of the snow. Compressed snow melts slower than light fluffy snow, so you can often find tracks embossed, or raised in the snow as the surrounding snow melts away. Here, we found a whole set of red squirrel tracks that looked like little ice buttons sitting on the surface of the snow. Once we spotted these I started noticing similar tracks everywhere - particularly the raised ridges of cross-country ski tracks. Sorry for the high contrast photos, but it was about the best I could do with the lighting (I had to ramp up the contrast to make them more visible).


Here the squirrel is moving away from the camera. It's two smaller front feet land in the middle, slightly offset from one another. The larger rear feet land after the front feet pick up and on the outside, in line with each other. Red squirrels tend to land with their feet more offset than gray squirrels. I think I learned this from Jim Halfpenny's tracking book: animals that spend more time in trees (e.g. gray squirrels) land with their front feet in parallel (like they'd been while perching on a branch) and animals that spend more time on the ground (e.g. rabbits) land with their front paws far more offset.


Where: The Intervale

Monday, January 14, 2013

Goodbye snow



What: I went for a wonderful walk on Saturday morning with my friend, Kate, to check out her topbar beehive. Her bees were reluctant to come out when we first arrived, but by the time we left the sun was out and it was about 43 degrees. Her hive is in full sun and has a dark cover, so it must have warmed the hive up much higher than that. Her bees were flying with great relish! I can only imagine the relief of being able to fly after spending a month and a half cooped up in darkness.

Bee flyling, yellow blotches on snow are their poop
They spend their time on warm winter days cleaning shop and making poop flights, for lack of a better term. The little yellow splotches in the photos immediately above and below are bee poop. We were both surprised at how much poop a single bee can poop; it was like watching a great blue heron or bald eagle fly over head and unleash a torrent of poop. 

bee poop on surface of snow
Inside the hive, bees shiver to maintain heat. To fly a bee needs to be at about 85oF. It'll shiver and spike it's temperature to about 100o before taking off. If the weather outside is too cold, the bees won't make it very far. But their temperature can drop pretty low before they'll die. Bees on the inside of the hive that are on the outside of the cluster can have body temperatures as low as 41o. Below is one unfortunate bee. The dark bodies of the bees absorb the heat from the sun, so many had melted down into the snow.


When we inspected a couple of the bees that had flown and landed on the snow we found some varroa mites, which Kate wasn't too happy about. They look like shiny water pennies (a type of limpet). Below is the best my camera could do, they're about as big as a grain of sand so they're hard to spot.


Where: The Intervale

Thursday, January 10, 2013

The Moon (part III)

Wednesday - Crosses light post around 11:50pm
Thursday - Crosses light post around 12:40am 
Here's the second thing I learned from photographing the moon last week, and this is visible in this set of photos here, is that the altitude of the moon in the sky changes when the moon as at the same bearing (direction on the compass) on each of the nights. That is, the arc that the moon follows across the sky each night is different. At this point in the lunar cycle, with each successive night the moon travels a slightly lower arc across the sky. I haven't the foggiest why this is, but it indicates that the moon's orbit around the earth isn't fixed. So the sun does this on an annual cycle (sun is lowest in the sky at Winter Solstice, highest at Summer Solstice), but the moon appears to do this on a lunar cycle. And why doesn't the moon just slip out of earth's gravitational field if its rotational axis wobbles around so much? And why does the moon always face us from the same direction?

Monday, January 7, 2013

Starling murmuration

 
 
What: On Friday, Brian, Meryl, Julia, Cecily and I went down to Snake Mountain for my sister's birthday. On the way back, we spotted a murmuration of starlings at the intersection of Mountain Rd and Rte 17 in Addison. 

We were mesmerized. Even watching the video, I kind of just sink into this lull where time dissipates. My naturalist mind drifts in and out, and I occasionally puzzle through how and why these brilliantly colored birds congregate in such a way, but my mind drifts just as quickly back into the gentle rhythms of the birds moving like fish through the sky. It's one of the most dramatic and muted winter events. Perhaps their banality (there are about 2/3 as many starlings as people in the United States) makes something like this easier to ignore.

Ecological notes: We watched them flying endlessly back and forth in these beautiful organic, fluid streams for about 45 minutes. The smaller flocks would drift in and out of one another, occasionally number in the 400-600 range, then splinter back into groups of 20-100. Very rarely would a starling be flying by itself. One of the more beautiful moments was when a flock would fly over the cattle barn, with a smaller group slipping off into the barn to roost. By the time we left (5pm) there was a cacophonous roar coming from the thousands of starlings in to roost for the night.

It seems like energy conservation is particularly important during the winter, and so this seemingly extravagant display appeared out of place. My initial guesses felt off - could they be socializing? having fun? bonding? vying for rank? Crows roost in such large numbers to stay warm, to socialize, and as I forgot while looking at the starlings, to avoid death by owl. It wasn't until a Cooper's hawk showed up that it started to make sense. When the starlings flap their wings it's visually confusing, and makes it hard to focus on any one bird. They constantly shift directions, in near perfect unison, and as they do their bodies go from fat round silhouettes, to thin slivers barely visibly against the flat light. The Cooper's hawk was there nearly as long as we were and made about a dozen attempts at catching a starling, each time returning to apex of the roof empty taloned.

I doubt it's as simple as predator avoidance (this works similar to dazzle camouflage which I wrote about in my post on locusts). The grace and elegance of the birds flying has it's own peace and quieting energy. Their movements etched these soft liquid lines in the still dusk air of winter, and it just felt good to be in their presence. Maybe it's the goodnight story of the starling. Maybe they do it simply because it's beautiful - like the revival chorus of songbirds in August, or the midnight singing of the hermit thrush, or the fall peeping of the spring peepers. Whatever the reason it was another way to fall in love with winter.

Where: Addison, VT. There's a considerable number of cows in that area (here's a link to where we saw the starlings).

Other notes: My sister, Meryl, is a fantastic film maker and cut together the video from footage she shot with her iPhone. For more of her work, visit: http://www.meryloconnor.com/

Saturday, January 5, 2013

The moon (Part II)

What: As a follow up to my last post, I wanted to post about why the moon cycles at all from new to quarter to full and back to new in 28 days. To get a sense of this myself I went out to Centennial Field the past three nights at 10pm, 11pm, and 12am to take photos. Below are the shots from 11pm on Tuesday, Wednesday, and Thursday nights. In New England, about half the days are good for viewing stars, so I was happy to get at least some shots of the moon between cloud breaks (Wednesday was easily the best, but it was super cold, last night the moon wasn't clear until the clouds broke around 12:20am).

Taken on Tuesday night at 11:03pm
Taken on Wednesday night at 10:58pm
Taken on Thursday at 11:00pm, moon hadn't risen yet
Two things come up in this. Apart from the lighting being totally different in each photo, note the different positions of the moon. This is true in two ways. First, the moon appears at a different bearing (direction on a compass) in each photo even though they were all taken within 5 minutes of each other on each night. Put another way, it takes a little longer than 24 hours for the moon to rotate a full 360o around the earth.

I remember that my calculations over a long period of time in Santa Barbara indicated that the time difference for the moon to get to the same bearing (not height, or altitude, but compass direction) in the sky was offset by about 52 minutes later each night. So each night the moon rises about 52 minutes later than the previous night.

For the moon to return to the same bearing in the sky at the same time of day/night, which is the same as completing a full revolution around the earth, it would take 24 hours (a full cycle) / 52 minutes, or approximately 28 days. 

Thursday, January 3, 2013

The moon


What: I've been trying to pay a bit more attention to the moon the past few months, and the last couple of nights I've returned to a project I started when I lived out under the stars in Santa Barbara. Astronomy completely perplexed me and I couldn't really understand anything I was reading about the moon so I decided to put the books down and just do my own research.

Here's what I've learned so far from observing the moon:
  1. The moon doesn't rotate along its own axis. Every night, regardless of phase, time of year, etc. the moon is always facing us with that same sonorous "face".
  2. It takes the moon longer to rotate around the earth than it takes the earth to spin in a full circle.
  3. It takes a little less than 53 minutes longer to reach the same point in the sky on each successive day (53 minutes goes into 24 hours about 28 times - each day the moon is 53 minutes further behind, after 28 days it has made a complete revolution)
  4. As a result the moon is in a different position relative to the sun by the time we can see it each night, resulting in a different "phase" of moon (I'll post a crummy drawing in a couple of days that will show this)
  5. If the section of moon that's lit up is on the west side the moon is waning (getting smaller), if it's on the east then it's waxing (getting bigger).
  6. On a full moon, the moon rises just as the sun sets, and sets just as the sun is rising
Photo I took of the full moon in October, 2012, compare with
the image of the waning gibbous moon, above right
I may be wrong on some of this so feel free to fact check me (just no using books). Nate (aka Gull, aka woodsmen drums smith) and I were just talking about the difference between smartphone apps like Moon Phase or websites like the moonrise finder and using primary experience to find things out. I think it's in the moments between finding the answers that are so important, like hearing the steel girders of the baseball stadium awning creak and groan and rumble like the belly of a ship as the temperature dropped (just as I could watch the moon move, I could almost feel the temperature drop from 2oF @ 7pm to -5oF at midnight). Using an app I would have missed the shooting stars blazing streaks across the sky. Perhaps in the end the information gleaned is the same, but the process is entirely different and I greatly prefer the long road, which is always home to many many divergent paths.

Other notes: Gibbous comes from the Old English "hump" or "hunch" and was used to describe hunchbacks before it was used to describe the moon.

Tuesday, January 1, 2013

Happy New Years


What: Snow! Everywhere! And what a treat after last year. I've been enjoying the wonderful snow piled up in Centennial Woods and pretty much everywhere - and with a few days for it to settle, shift, and change, there are so many different types. I started making blinds for my window and needed some more Phragmites, so I went out with Meryl and Nate around dusk to harvest. We were gifted with a beautiful sunset and we went to the baseball field for a better look. I took the above facing almost due east through the powerlines. The summit in the back is Mt Mayo (which is just south of Mansfield, between Clark and Bolton). The pink light was just radiating off of everything, settling a peaceful quiet over the pines, oaks, and maples. There was a scattering of wispy cumulus breaking up as they were heading southeast.


Ecological notes: I got a bit of tracking in after all that snow. The deer were already on the move Friday night. By Saturday there were tracks from red foxes, mice, and a weasels. Winter brings so many new interests - I've been particularly fascinated by all the different types of snow and I'll be posting on that along with winter buds this month! So stay tuned.