This busy week, most of my visits to Bear Creek were at sunset.  As the low winter sun created long slanting shadows across the fields, birds sought places to spend the night. Some birds floated in large groups covering the trees like black leaves.  Others slipped into holes and crevices.  And a couple of them even duked it out over a snug retreat on a cold night. I’ve become a watcher of holes this year.

A Bluebird Couple

Though many Eastern Bluebirds (Sialia sialis) migrate south, some stay near their summer breeding grounds,  eating fruits from sumac, juniper, multiflora rose, and spending the nights in tree holes.  Late on the Sunday after New Year’s Day, my husband and I saw a bluebird pair.  They were foraging on the ground and then flying, separately, up into small trees on our way to the western slope. This particular male is undoubtedly the bluest Bluebird I have ever seen! He definitely had a courtship advantage!

After getting a photo of the female, I learned that their gray heads identify their gender. Bluebirds often stay together for multiple seasons if they breed successfully.  I’m not surprised that this female decided to stick with that gorgeous blue male!

The next day, I went alone to Bear Creek as the sun was setting and snow was falling steadily in a strong wind.  I was delighted to find a pair (probably the same ones given the male’s intense blue!) near the shed, sitting together on a branch.  Please forgive the slightly blurred photo – the combination of low light, extreme cold and blowing snow made getting a shot a little difficult.

A Smallish Murmuration of Starlings

European Starlings (Sturnus vulgaris) are famous for giant gatherings of thousands of them, creating huge, moving sky sculptures over European cities.  Watch a minute or so of this  beautiful video from Gretna Green, Scotland to appreciate the beauty these birds can create. According to the Cornell Ornithology Lab,  these non-native imports are great mimics, who can copy the songs of “Eastern Wood-Pewee, Killdeer, Meadowlarks, Northern Bobwhite, Wood Thrush, Red-tailed Hawk, American Robin, Northern Flicker, and many others.”

In the fall, Starlings molt into feathers with white tips so in winter, their breasts are beautifully mottled in white.  As the winter wears on, those tips wear off so that by spring, they are all glossy black with purple and green iridescence  – what scientists term “wear molt.”

A small murmuration of starlings arrived in Bear Creek the same afternoon that the Bluebird couple waited together in the tree.  Evidently, the park provided a pre-roosting spot, a place to gather a couple of  hours before dark, to socialize.  Our murmuration consisted of about 200 birds in five trees near the eastern edge of the park. They floated in groups up out of the fields, or across from other trees, looking like black leaves defying gravity. Periodically they chorused for several minutes and then all fell silent – until the chorus began again.   Near dark, as I left the park, they had dispersed in small groups, probably to an even larger night-time roost with other flocks.

 

Starlings, introduced into the US in 1890s, aggressively compete for nesting sites with Bluebirds, which is one good reason for posting bluebird boxes!  I didn’t see Bluebirds in Bear Creek the next day and wondered if they found all those starlings a bit off-putting!

Native Winter Birds and Their Holes, I think…

As the snow fell in the Oak-Hickory forest,  a Tufted Titmouse (Baeolophus bicolor) flitted among the branches. They seem to never sit still for more than a few seconds!  Like Chickadees, whose company they often keep, they beat on seeds with their beaks to break them open for eating, though they also store some in bark crevices to be retrieved later.  (Click on the photos to enlarge. Hover over the photos for captions. The blurred one, taken as the wind blew, was so endearing, I had to include it!)

Nearby a Red-bellied Woodpecker (Melanerpes carolinus) explored near what could be its hole for the night.  You can see him in the background of the left photo at the edge of the tree.  The second shot is of another male Red-belly probing the bark on a tree near the Center Pond as the sun catches his red nape.

Woodpeckers are everywhere in the park now, spiraling up and around trunks and branches.  I saw a female Downy Woodpecker near the Playground Pond and nearby, at the wetland north of the playground, her slightly bigger relative, the female Hairy Woodpecker.  They’re not easy to tell apart, but the Hairy’s beak is thicker and almost as long as its head whereas the Downy’s is more delicate and smaller, about 1/3 of its head size.  Also, the Downy has black spots on its outside tail feathers when seen from underneath whereas the Hairy’s are pure white on both sides.  Males of both species have red spots on the backs of their heads. Females don’t.

Late one afternoon, we saw two birds which appeared to be competing for the same hole. For a split second, a White-Breasted Nuthatch (Sitta carolinensis)and a Black-Capped Chickadee (Poecile atricapillus) flew at each other, feet thrust forward  in a flurry of wings – but the Chickadee withdrew and flew off.  The Nuthatch, triumphant,  disappeared into the hole.  I caught only the aftermath with my camera.

As I said, I’m keeping my eye on holes.  Here’s one high over the back of the Playground Pond that I’m watching.  After taking this photo just before dark last week, I lightened the hole to see inside.  It’s probably wishful thinking, but could that be a small bird inside this comfortable little hole? Probably not, but I’ll keep looking anyway.

A Wintering Mammal –  and the Tracks of Two Others?

An American Red Squirrel (Tamiasciurus hudsonicus) scurried among the branches of a brush pile near the Center Pond and finally emerged with a large nut, or perhaps a fungus, in its mouth.  That probably got eaten before bedtime – or perhaps added to its winter food cache.

This week a Meadow Vole/Field Mouse  (Microtus pennsylvanicus) seemed to have tunneled under the snow near a log. The tracks looked just like a more complex set in deeper snow that I saw last year.

I can’t be sure who made them.  But voles are active during the day in the winter. (At night during the summer.)  They scurry about feeding on seeds and grains.  For a look at a Meadow Vole, one that gives you a sense of its real size, I recommend the photo at the bottom of this link.  Very attractive little rodent and an important part of the food web (but can be quite a pest in one’s lawn!).

One other set of mystery tracks caught my eye.  (And please – if you are a tracking expert, correct me on track photos!)  Down at the pond, I saw these canine tracks making a neat line curving along the edge of the pond.

According to the website Wildernesscollege.com, both gray and red foxes place their hind foot squarely inside the print of the front foot.  And unlike dogs, their tracks are very direct, not wandering off center or doubling back like dog tracks.  Wild canines want to leave as few tracks as possible, I guess!  So because these tracks are fairly small, I’m thinking these came from a Red Fox (Vulpes vulpes) who  took a shortcut across the ice at the edge of the pond while out in the moonlight.  I wish I’d seen it!  But here’s a photo of one who’d caught a mole at the edge of our woods a few years ago.

Winter is clearly a challenge for birds and animals.  Owls need to pounce into the snow for prey.  Small creatures can’t help leaving tracks to follow.  Food and warmth are a constant challenge.  But there they are, hopping in branches, trotting along in the moonlight, keeping us company on the grayest days of winter.

*Footnote:  My sources for information are as follows: Ritland, D. B., & Brower, L. P. (1991);Stokes Nature Guides:  A Guide to Bird Behavior Volumes 1-3, Allaboutbirds.org, the website of the Cornell Ornithology Lab at Cornell University; Wikipedia; http://www.butterfliesandmoths.org; Herbarium of the University of Michigan at michiganflora.net; various Michigan Field Guides by Stan Tekiela; Butterflies of Michigan Field Guide by Jaret C. Daniels; University of Wisconsin's Bug Lady at www4.uwm.edu/fieldstation/naturalhistory/bugoftheweek/ for insect info http://www.migrationresearch.org/mbo/id/rbgr.html for migration info; invaluable wildflower identification from local expert, Maryann Whitman; experienced birder Ruth Glass, bird walk leader at Stoney Creek Metro Park for bird identification; Birds of North America Online; Audubon.org, Nature in Winter by Donald Stokes, Trees in My Forest by Bernd Heinrich, Winter World by Bernd Heinrich, Savannah River Ecology Lab (Univ of Georgia), Tortoise Trust website www.tortoisetrust.org and other sites as cited in the text.