Guest Post: Ice Discs

Enjoy this guest post about an unusual ice phenomenon from naturalist Larry Youmans, who lives in the Flathead Valley:

I had the camera trained on a perfect 40-foot circle of ice.

This was my second disc sighting, same place, and same disc size. I looked down on the river at the snow-shrouded Glacier Rim Boat Landing, a public access boat ramp. If you stand on the ramp, facing the river, you’ll notice the stream crooks and drops a bit. When the conditions are right, ice discs can form at this spot.

The North Fork of the Flathead River system is a young tributary, a young river with history. One event in its history is the ice disc.

Born about 15,000 years ago during those turbulent times of glaciation, the North Fork has mysteries in its past. Not a long river, it flows south and slightly west along the border of Glacier National Park. As you float this stream there seems to be a series of long pools that slough off to the right at the downstream edge.

Over time, receding glaciers gradually made the North Fork longer and longer. At the boat access, the river flows over bedrock, making this a very old stretch. This stable portion of flow, over time, has probably produced many discs.

River ice circles are an uncommon phenomenon, with sightings ranging globally in colder climates. The few photos of ice discs on other rivers indicate a consistency in stream shape.

Theories on their formation, and there are many, range from chunks of ice breaking off and grinding in one spot, to alien intervention. It would seem this is a North Fork secret.

Here is one theory: Precipitation changes flow all the time. The build-up of winter snow on the banks reduces the river’s flow. At the boat landing, where the river drops, the right flow can produce a subtle flat swirl or eddy.

As the temperature decreases, it is possible for ice to form in the center of that quiet patch of water. Ice also forms inward from the riverbanks, which causes upstream flow to slow even more. As ice at the center of the swirl expands toward the current, it might start to rotate, forming a perfect circle where it meets the ice growing from the river’s edge.

The reality is there’s no clear understanding of how these circles form. However, I took these photos on Jan. 21, 2014. Historical data indicates Kalispell, Montana, temperatures on Jan. 20 through Jan. 22 ranged from a high of 33 degrees to a low of 12 degrees. The river discharged an estimated 520 cubic feet per second at Glacier Rim on Jan. 21, a common flow rate for the early months of the year.

This portion of the North Fork River may have produced many ice circles over the years. I’ve seen two. If I’m lucky enough to see a third, I will spend more time appreciating this rare phenomenon.

~Larry Youmans

Guest Post: Mystery Butterfly

Observations & photos submitted by naturalist Kim Birck, late July 2014.

Yesterday a butterfly I’d never seen before visited my yard. It had the colors of a swallowtail, but no tails, and it didn’t match anything I could find by doing a Google image search for “black and yellow butterflies." So I posted a (low-resolution) smartphone photo to Facebook and got an immediate reply from a cousin in Wisconsin--“Could it be a Mourning Cloak?” Though the Mourning Cloak is Montana’s state butterfly and does frequent my yard--and its general morphology is somewhat similar--I’d already ruled out Mourning Cloak using the eNature.com online butterfly field guide.  

However, eNature was no help in figuring out who the mystery visitor actually was. The categories I might have chosen from their list--swallowtails or “boldly patterned”--produced no results. This was a very cooperative butterfly, however, hanging around all day and posing prettily on the bee balms (Mondarda sp.) that have proliferated where the native vegetation catches overspray from the lawn sprinklers. So I was able to get several good shots with a real camera, and e-mailed one to my friendly local naturalist at the Montana Natural History Center, Brian Williams. 

Twelve hours later, I had a reply: “Hi Kim, Great picture and good butterfly--it's a female Great Spangled Fritillary. Charles [Miller] and I were out in the Rattlesnake yesterday and saw one ourselves! Perfect timing on your question too, I've been working on my fritillary ID skills the last two weeks.” 

I Googled Great Spangled Fritillary, and on the Wikipedia page found the reason why it was so hard to identify: “Females tend to be darker than males and individuals from the western reaches of this species range tend to be brighter orange.” Talk about an understatement! All the Great Spangled Fritillary images I’d ever seen were brown and gold. Who knew the sexes were practically dimorphic? Today, a couple orange-colored males were chasing each other around the yard, and one landed on the same flower as the female I was photographing. She took off, but here’s the male.

He appears a bit the worse for wear as the markings have faded, near his wingtips, especially. 

Here are views of the undersides of their wings: Male:

and Female:
 

After seeing them fluttering around, I had a few more questions for Brian: 

"How do you distinguish Great Spangled from the OTHER Fritillaries? Could GSF be easily confused with the Northwestern Fritillary?" 

He responded: "Well, identifying the fritillaries besides Great Spangled is my summer's million-dollar question. Luckily, the Great Spangled is the one (of 10 or so, it seems), that is most readily identified. The best characteristic is the nature of the silver spots on the bottom of the hindwing--in the Great Spangled, the spots are relatively few, small, and well-spaced compared to all the rest of the fritillaries (like your photo, which is indeed a Great Spangled). The Great Spangled is also a bit bigger than all the other fritillaries. So, while at first glance, the Northwestern and Hydaspe Fritillaries are similar to Great Spangled in overall color, it is possible to distinguish them in the field. Beyond Great Spangled, the question is much more muddied. Charles and I have been collecting fritillaries for a display and I've actually been submitting photos of our pinned specimens to the website 'Butterflies and Moths of North America' to get positive identifications. Good fun!"

(Now we know what naturalists do when they aren't leading field trips!) 

Natural History Information from the Butterflies and Moths of North America Website: 
Great Spangled Fritillary 
Speyeria cybele (Fabricius, 1775) 
Family: Nymphalidae 
Subfamily: Heliconiinae 
Identification: Large. Upperside of male tan to orange with black scales on forewing veins; female tawny, darker than male. Underside of hindwing with wide pale submarginal band and large silver spots. 
Wing Span: 2 1/2 - 4 inches (6.3 - 10.1 cm).
Life History: Males patrol open areas for females. Eggs are laid in late summer on or near host violets. Newly-hatched caterpillars do not feed, but overwinter until spring, when they eat young violet leaves. 
Flight: One brood from mid-June to mid-September. 
Caterpillar Hosts: Various violet species (Viola). 
Adult Food: Nectar from many species of flowers including milkweeds, thistles, ironweed, dogbane, mountain laurel, verbena, vetch, bergamot, red clover, joe-pye weed, and purple coneflower. 
Habitat: Open, moist places including fields, valleys, pastures, right-of-ways, meadows, open woodland, prairies. 
Range: Alberta east to Nova Scotia, south to central California, New Mexico, central Arkansas, and northern Georgia. 
Comments: The most common fritillary throughout most of the eastern United States. 

Community Observations: What are you seeing?

Spring has arrived in a glory of rain and sun and flowers and green things growing.  It's a great time to be out and about, observing the natural world!  The staff at MNHC have been seeing lots of fun things:  Great Horned Owl young in a nest at Council Grove; Lazuli Buntings at Bass Creek in the Bitterroots; American Dippers braving wild run-off waterfalls along Sweathouse Creek; Osprey soaring over the Clark Fork River, looking for fish; the bright colors of Western Tanagers in back yards around Missoula; and dozens and dozens of wildflower species, from lupine to paintbrush to side-flowering mitrewort to fairy-slipper orchids.  


Where are you exploring this spring?  What are you seeing?  Please share in the comments!

Mystery Tail!

One of our staff naturalists brought in a tail that she found near her property in Lolo.  It is rather flat, but that may be due to the fact that it was buried under a thick layer of snow for much of the winter.  Does anyone have any guesses as to what it may be?

                    Click on the pictures for a bigger view.

We have a few guesses as to the species here at MNHC, but we aren't quite sure, so we're open to any suggestions and thoughts you may have.  Please share your ideas in the comments!

What Have YOU Seen?

We so appreciate Kim Birck sending us her observations this summer, and we want to know what everyone else is seeing on their excursions out and about in Montana (and beyond!).  So, what have you seen this summer?  

Moose?  

Grizzlies? 

Bald eagles?  

Cedar waxwings?  

Here's a picture of a western tanager that I saw while hiking up the main trail of the Rattlesnake at the beginning of the summer:

Post your observations in the comment section, or send an email to adejong [at] montananaturalist.org if you have pictures you'd like to share.  We can't wait to hear from you!

American Dipper Nest

We have a few more pictures from MNHC friend Kim Birck, this time of an American Dipper nest she and her husband observed while backpacking in Idaho's Sawtooth Wilderness.  Here are her comments:

These pictures are of the mossy nest of an American Dipper (Cinclus mexicanus), also known as the Water Ouzel. The dipper was reportedly John Muir's favorite bird. The name "dipper" is for the bobbing motion this little gray bird makes as it stands on a rock or log in fast-moving water.

This nest was located on the side of a large rock in the middle of the falls between Middle and Upper Cramer Lakes in the Sawtooth Wilderness area near Stanley, Idaho. 

We were camped right above the falls from July 24 - 27, and were able to watch the parents coming and going, and hear the excited noises made by the chicks during each visit. 

According to my bird books, both parents feed the young, but the female does most of the work. We witnessed both parents in action, though we could not tell who was who. This may have been a second nesting, as the bird books indicate that dippers nest as early as late April. (Or maybe because of the elevation and late snowmelt, it could be a first nest.)

We watched the parents "dipping" and walking right into and under fast-flowing water in search of aquatic invertebrates to feed their young. As they entered the water, we could see a couple of their adaptive features: the protective white nictitating membrane that slides over their eyes and the extreme water repellency of their feathers.

We have seen dippers in the Missoula area, particularly in the upper reaches of Grant Creek, and have been aware that they had a nest - somewhere - but this was the first time we could actually SEE a dipper nest and watch the feeding activity.

It was fascinating to watch, and listen to, the dipper family during our 3 nights on the Cramer Lakes. 

Photo Essay of a Cordilleran Flycatcher Nest

The past few weeks have been nesting time for many birds in our area.  One of MNHC's long-time volunteers and supporters, Kim Birck, has been watching one type of bird--and one nest--in particular, a pair of Cordilleran Flycatchers (Empidonax occidentalis) who chose her power box upon which to build their nest.

Cordilleran Flycatchers are small birds with greenish-brown backs, yellowish underparts, and a slight crest on the head.  Distinctive features include a pale yellowish eye ring and wing bars.   The Cordilleran flycatcher is virtually indistinguishable from the Pacific-slope flycatcher--in fact, they were once thought to be the same species and were called Western flycatchers.  The only difference between the two species is the male's voice--and their range.  Cordilleran flycatchers breed in a long north-south swath of the western U.S., from southern B.C. and Alberta into Idaho, western Montana, Wyoming, Utah, Colorado, Arizona, New Mexico, and into the northern edge of Mexico.  

Flycatchers are so named for their feeding habits; they swoop down from their perches and catch flying insects in mid-air, though they will also hunt for insects hiding in the branches of trees and shrubs.  Some flycatcher species will also eat berries or other types of food. 

Cordilleran flycatchers are commonly found in dry, shaded forests at mid-high elevations. 

While they usually nest in trees, occasionally they'll find other convenient locations--in Kim's case, the top of her power box at her home.  She was very happy to share with us both her pictures and her observations.  Enjoy!

24 May:  I just saw a little Cordilleran flycatcher yesterday, back from wherever he/she winters.  (Mexico, it seems.)  Maybe my power box will have another nest, for the 5th year running! 

9 June:  He's back again!  I was repotting herbs nearby while my little flycatcher friend was checking out the nesting site on top of the power box. 

10 June:  Well, today, THIS showed up!

11 June:  I hope I haven't scared him/her off . . . perhaps not.  The nest looks bigger today:

12 June:  She's at it again today.  Watched her mashing down the nesting materials (mostly lichens and moss?) with her body.  Here's a fuzzy image of her on the nest:

Fuzzy because I used digital zoom, not wanting to get close enough for optical zoom.  Once she has eggs, she'll be harder to dislodge.  But for now, I want to keep her as my neighbor.  Seems like good luck to have a bird nesting on your house.

14 June:  Set up a bicycle mirror on a broomstick that allows me to see into the nest.  No eggs yet!

She isn't around much lately.  I suspect she is gathering her strength after nest-making before egg-laying, as my book (Peterson Western Birds' Nests) says the female does the nest building and the incubating.  One egg per day for a clutch of about 4.  When the clutch is complete, she incubates for about 14-15 days, then both parents feed the nestlings for about 2 1/2 weeks before they get too big for the nest and fledge.  

15 June:  I hear them calling, so I know they're around . . . but still no eggs.

17 June:  This morning, before we left on a 2-week trip, I checked the nest and there was one egg!  During our absence, she should complete the clutch and do most of the incubating . . . and be fully committed to the nest by the time we get home.  BTW, my husband recently admitted that when he was blowing dust and pine pollen off the porches and windowsills with a leaf blower he accidentally blew the flycatcher's nest off the power box.  He carefully replaced it and it seems to have worked.  The egg this morning is the proof!

2 July:  When we returned home, I found mama flycatcher sitting on these:

Note the brown splotches wreathed around the large end of the egg.  This is typical for Cordilleran flycatchers.

4 July:  Mama bird was acting restless, spending more time looking into the nest before settling back onto the eggs.  Since the bird book says they incubate for 14-15 days, I knew hatching was imminent.  

5 July:  This morning when I looked into the nest, there was only one egg left, plus three naked lumps of baby bird flesh:

Mama continued to incubate the nest,  when I thought she should be out catching bugs for her babies . . .

6 July:  We were cleaning windows this weekend and my husband went up on the roof above the breakfast nook--and the flycatcher's nest on the nook wall--to wash the upstairs windows.  I was tending plants nearby when I heard a flycatcher "shreek!" and saw it streak away from the house.  I looked up to see size 11 white tennis shoes hanging over the roof edge right next to the nest as he stretched to reach windows on the adjacent wall!  No wonder she fled!  I hoped that our maneuverings near her nest hadn't spooked her for good.

But she came back has been diligently "sitting on" the babies, all four of which had hatched by last night.  And at least one was alive last night, raising its little head--and gaping big mouth--when the mirror loomed overhead as I checked it out.

I have yet to witness food being brought to the nest, though.  Not to say it hasn't happened, I just haven't seen it.  We are trying to keep a low profile and avoid disturbing her, though her instincts would probably not let her abandon the babies now.  The windows closest to her nest are going unwashed, and I only photograph the nest when she has flown away.

7 July:  This morning:

Baby flycatchers sleeping while Mama is away.  And now I'm seeing TWO flycatchers.  And finally, late this morning, witnessed an insect being fed to somebody in the nest!  

4 pm:  Still spending a lot of time on the nest, even though the young are all hatched.

Both flycatchers--hard to catch them together as they are finally actively bringing insects to the nest this afternoon!

8 July:  I caught the nest unattended briefly this afternoon and snatched this image:

They are starting to look just a bit like baby birds.  Less like raw meat anyway.

11 July:  I frequently catch an adult feeding the young in my mirror, hanging from the eaves, but they won't come to the nest when I am outside with my camera.  Taken on Sunday, in the hanging mirror.  I can watch them from inside the kitchen without disturbing the birds. 

16 July:  I took this photo from a 6-foot ladder about 6 feet away from the nest while the parents were away:

Their mouths are open because they're hot (and hungry).  They are beginning to overfill their nest.  And now I can see that all 4 have survived.  So far.  Ravens prowl the neighborhood looking for such tasty morsels!

17 July:  The first three babies hatched on July 5, and the Birder's Handbook (Ehrlich, Dobkin & Wheye) says they are in the nest 14-18 days before fledging.  So they will have to grow up a lot in the next few days as today is Day 13!

19 July:  The afternoons have been quite hot lately, and the little ones look like this a lot of the time:

They wake up pretty quick when Mom or Dad arrives with a tasty insect!

Sometimes the parent bird gives a heads-up "peek!" as it arrives, so the little ones assume the position and no time is wasted.

20 July:  We are off for a week-long hiking trip.  The baby birds are about to fledge, and will probably be out of the nest by the end of the week!  A fifth season of nest-watching is ended.

Owl Trapping with Denver Holt

The following incredible pictures were taken by UM graduate student Tom Rogers on a recent outing with Denver Holt.  The field trip was part of the University of Montana's Avian Field Techniques course taught by Professor Dick Hutto and two graduate students.

The group spent the day trapping long-eared owls as part of Denver's long-term study monitoring owl numbers in Western Montana.  The team used a misty net for capture, walking up and down the woody draw to flush the owls into the net.  Trained handlers were in charge of processing the birds: taking their wing cord, mass and sex estimate (based on feather patterns).  After this information was collected, the owls were released safely back into the wild.

Long-eared owls have an average wingspan of 86-98 cms

This is an owl ear, believe it or not!

Tom also reported the team saw a Great Horned Owl nesting in the draw.  So cool!  For more information on Denver Holt and his research, visit the Owl Research Institute here.