Tuesday, April 30, 2013

Silver maple - an update on the twig

What: A short interruption (tomorrow as well for first of the month) on the spring ephemerals to bring you an update on the silver maple bud I've been watching. The leaves on the twig have started to burst open! Also, the flowers have largely been pollinated and are starting the short journey to ripening (they look like purplish mini maple seeds). For more information, see my two previous posts on the silver maple twig.

April 3 post: click here
March 29 post: click here

Monday, April 29, 2013

Spring ephemeral a day - Early meadow rue

What: Last Wednesday, Leah, Sophie, Brooke and I took an early morning trip out to Red Rocks. The sunrise was gentle and elegant over Shelburne Bay. It was serene watching the ring-billed gulls cut lines across the water. We watched a few lines of cormorants heading north. Beneath our feet, we enjoyed the first of the spring ephemerals shivering their way up in the leaf litter. I was particularly captivated by the beauty of the early meadow rue (Thalictrum dioicum) unfurling into itself.

Ecological notes: Early meadow rue is superficially similar to blue cohosh (Thalictroides caulophyllum, thalictroides = thalictrum: thaliktron, Greek name for plant similar to meadow rue + -oides: resembling, looks like, so blue cohosh is the plant that looks like the plant that looks like an unknown plant that Dioscorides described in Greece). Blue cohosh looks like a beefed up, simplified meadow rue (I'll post about blue cohosh soon). Besides the shapes of the two plants being similar, the most notable similarity is their color. Each emergent plant has a deep purple tint to it. As the plant unfurls, it loses this coloration. My guess would be that, as a tree's leaf has yellows and oranges and other fall colors throughout the growing season, they don't show these colors during the growing season as the density of green chlorophyll increases and overshadows other colors in the leaf.

Where: Red Rocks, growing along the cliffs under scattered white cedar (Thuja occidentalis) and common red cedar (Juniperus virginiana).

Other notes: When I was first learning plants, I didn't know about Newcomb's wildflower guide and was more or less on my own. So I just made up names for them. This was the only plant I remember. I called it bear paw because the leaves reminder me of happy little bear feet dancing across the forest floor.

Thursday, April 25, 2013

Yellow bellied sapsucker

Male yellow-bellied sapsucker (females lack the red "beard")

What: One of my students found a yellow-bellied sapsucker (Sphyrapicus varius) that had died near her house (no sign of predation, perhaps flew into a window). The next day we got to watch a sapsucker drilling holes in a bitternut hickory (Carya cordiformis) and licking out the sap. I propped open the bird's mouth with an elderberry twig to show the bristles that line the tongue. Birds can't "suck" like we can from a straw, so having the hairs allows the woodpecker to lick up much more sap than a smooth tongue would be able to. The hairs work via capillary action, which is the ability of water and other liquids to overcome the force of gravity via intermolecular attractive forces to solids. This can be seen readily by holding the tip of a napkin in water and watching the water travel up the napkin. So all that surface area acts as a magnet of sorts and the little birdie can lap up even more liquid.

Ecological notes: Sapsuckers make distinctive horizontal rows of sapwells. It's interesting to note that we had tapped a bitternut hickory and hadn't gotten any flow. The sapsucker showed up just as the sap started dripping into our buckets. While the sapsuckers miss the better flow of maples, they have been recorded utilizing over a thousand different species, so there's plenty for them to go after.

I was also impressed by the incredible sharpness of the claws. I could easily perch the bird on my finger from just one of its claws. It's feet kept getting caught on everything because they were so sharp. Must be an adaptation for gripping a tree as the bird fiercely bangs its head against it while making its sapwells.

Where: Rock Point, Burlington

Tuesday, April 23, 2013

Millipede graveyard

What: At Crow's Path a couple of weeks ago, Lauren and one of the kids discovered a cemetery of millipede exoskeletons. The big question was whether or not they were sheds or if all of the animals had died. There wasn't any sign of cracking along the back (as in the cicada molt below), so my suspicion is that there was a big flush of them and they died. Polydesmida millipedes typically have very small home ranges and so are locally concentrated, which may explain why we found sooo many in one small outcropping (http://www.polydesmida.info/polydesmida/).

The top image shows gives a clear view of the full body of the millipede. There are 20 countable body segments. This is apparently diagnostic for members of the Polydesmida family, which all have between 18 and 22 segments. Because the colors had all been bleached away by time, it would be hard to identify down to species. The family gets its common name, flat-backed millipedes, from the lateral blade-like ridges, called paranota, poking out from the sides (apparent in photo at bottom of posting).

Differences between millipedes and centipedes: The image below shows a single body segmented with two pairs of legs. Millipedes have 2 pairs of legs per segments (centipedes have 1), short legs that don't extend much beyond their body (centipedes have long legs), they don't bite (they're scavengers, centipedes, which are predators, do bite), and millipedes are slow (centipedes, again are hunters and are very quick).

Where: On the moss-covered rocks at Rock Point

Thursday, April 18, 2013

Witch hazel seeds

What: Once I found out that witch hazel (Hammemelis virginiana) has projectile seeds I got really excited about seeing that process. I've been watching witch hazel all winter, and just last week I noticed that all of the capsules at Rock Point had finally split open, scattering seeds all about!

Ecological notes: Apparently the capsules can take up to 2 years to develop. Warmth triggers the capsules to pop open (they make a loud popping noise). So I suppose you should be careful about taking unopened seed pods inside. These guys opened when the weather was in the mid-50s. I included a couple of photos from previous falls, the first with the beautiful stringy yellow flowers, the second with developing capsules. 
Witch hazel flowers (photo taken at end of September)

Developing seed capsules (also taken in the fall)
Where: Rock Point

Other notes: The name witch hazel derives from the Old English wiche (probably akin to wicker), which means pliable. Hazel is adopted from the common name for European species in the genus Corya (like our native beaked hazelnut, Corylus cornuta).

Tuesday, April 16, 2013

Owl feathers

What: I found these owl feathers strung up in a yellow birch sapling at Rock Point. The feathers had been plucked from the body of the bird (there was still some flesh attached to some of the cluster of feathers indicating it hadn't just molted the feathers). Here's my process of elimination for identifying them to species:

Detail showing "fuzz" on the feathers
  • Owls have fuzzy feathers along with a leading edge of "prongs" that make it look like a comb. These together channel air over the feather (black box of physics for me) that allow the bird to fly in utter silence. Raptors (Falconiformes) have this as well, but not nearly as well developed as in owls (Strigidae). 
  • In Chittenden County, there are records of 10 owl species, according to eBird.org. Six of these species are extremely rare (barn, snowy, hawk, great gray, long-eared, and short-eared owls). This leaves me with four probable species: eastern screech, great horned, barred, and saw-whet owls.
  • Using the book Bird Feathers and the online Feather Atlas I was able to narrow it down to further. The largest feather is a flight feathers (one of the secondaries on the wing). Flight feathers are asymetrical, have a bend when looked at both in profile and head on, and the tail edge of the feather curls up slightly.
  • The white bands on barred owl flight feathers cut straight across the feather. These were just white blotches on the trailing end of the feather.
    • Barred owls also have 2 distinct colors of brown. 
  • Screech owls also have 2 distinct colors of brown on their primaries. I've also seen these before and they tend to have an orangey/reddish hue to them. 
    • The white on each feather makes a clear triangular shape
  • Given size (about 3.5" long), color (one solid color of brown), and pattern of white dots, it seems like Northern saw-whet is the best match.
We have a pair of barred owls that we see and hear frequently around Crow's Path. My guess is that the saw-whet was eaten by the barred owl, which are apparently common predators of saw-whets. I looked around briefly for pellets but didn't find any. Pretty neat stuff!

Where: Rock Point in Burlington

Other notes: Great resources are the online Feather Atlas and the book Bird feathers by S David Scott and Casey McFarland

Sunday, April 14, 2013

Bird a day - Blue jay

What: There's a family of 5 or so that moves through this area making a total ruckus. I keep getting my hopes up, thinking that all their alarms are directed at a predator (I've seen a Cooper's hawk nearby on quite a few occasions in the last couple weeks). But every time it's the same: nothing.

Here I couldn't figure out what the bird was doing until I looked at the picture later. Initially it looked like it was peeling bark off the tree and eating it. Turns out it had found a peanut too big to swallow whole and it was tearing it into manageable sizes to swallow. It was gripping it with its feet and ripping up with its head. Pretty neat to see it solve the problem of size.

Where: Silver maple in my yard

Other notes: Tis the season for wildflowers. Skunk cabbage, hepatica, coltsfoot, and squill are all up. Wood frogs eggs are starting to fill the ponds, spring peepers are singing at Shelburne Pond, and buds are starting to bust!

Saturday, April 13, 2013

Bird a day - White-breasted nuthatch

What: Perhaps one of my favorite birds. I think I like them so much because of their adorable little tushies, that little red ring around their cloacas is adorable. The photo below is classic nuthatch posture when it feels slightly nervous or when it's looking for greener pastures. They're one of the few birds that can move downwards along a tree's trunk. In the photo above I happened to catch it mid-hop!

Ecological notes: I watched the nuthatches "drumming" on the trees - they seemed to be prying bark off to get at little insects underneath. I watched them on super cold days doing this and wondered how much of their behavior is based on blind luck. Since insects wouldn't be moving around (temperatures where subfreezing) then they couldn't hear them. They'd have to smell them (most birds can't smell), see them (they were peeling the bark off to get underneath where the bugs were), see sign of their presence (like entry holes, feeding sign etc, indicating the birds are awesome trackers), or rely on dumb luck that peeling off enough bark will ultimately yield enough calories to stay warm.

Where: Silver maple in my yard

Friday, April 12, 2013

Bird a Day - Hairy Woodpecker

What: These are a couple of shots of the female hairy woodpecker. For notes on the difference between this little gal and the very very similar looking downy woodpecker, see yesterday's posting. In short (or long), the hairy woodpecker's bill is considerable bigger relative to body size.

Where: The silver maple in my side yard

Other notes: I remember reading Sam Thayer saying that he only wrote about wild edibles that he had tried himself. I really like that perspective, and I was reflecting on what I've included in this blog. A lot of it has been citations of the work of others, stuff that I hadn't observed in person. I think reading this has pushed a lot of my thinking, but it also has substituted for actual experience. While observing the hairy woodpecker feeding on the maple, I realized how little of substance I had to say about this creature and felt bad. I suppose that's my challenge over the coming weeks, to better know the hairy woodpeckers that are my neighbors.

Thursday, April 11, 2013

Bird a Day - Downy Woodpecker

What: Female downy woodpecker above. Male shown below, note the visible red blotch on his nape. Sex is pretty easy to determine for most of our woodpeckers. General rule: If it has red on its head it's a male, if not it's female. Beware, as this doesn't always work (as with pileated woodpeckers - both have red on their head).

Hairy woodpeckers (coming tomorrow) can be really difficult to tell the apart from downys. A hairy woodpecker is beefed up downy woodpecker (hairys are about the size of robins, downys are just slightly bigger than titmice). My old roommate, and fantastic naturalist, Emily Stone, used the following mnemonic:

    "What bill??" - downy woodpecker
    "What a bill!!" - hairy woodpecker

Note that the downy has a thin narrow bill shorter than the bird's head is; hairys have thick chunky bills longer than the diameter of the bird's head.

Where: Silver maple in my backyard

Wednesday, April 10, 2013

Bird a Day - Cardinal

What: We've had cardinals successfully - and unsuccessfully - fledge young in our backyard. This male has been courting a couple of females, so hopefully this will be a "successful" year. Females have the same body shape, but are a waxy yellowish color with dustings of red on the sides. Their songs (and both males and females sing) are simple, but variable. They have that same sweetness to them that the titmouse has, but cardinals tend to sound more like a toy laser gun. Birdie Birdie Birdie Pew Pew Pew Pew.

Where: The silver maple!

Other notes: Their nests, which certainly aren't the tidiest of affairs, are often placed in super shrubby thickets where they have access to lots of cover (which is partly why they like honeysuckle so much). They always use strips of grapevine bark in the outer layers of their nests. Not sure why, perhaps to help conceal their nests from predators. In Medicine Quest Mark Plotkin describes eagles that select medicinal twigs to line their nests with (supported by research from Ohio Wesleyan). I looked up medicinal uses of grapevine bark and couldn't find any references, maybe the cardinals know something we don't?

Birds can't produce red pigment on their own, so in order to display a red plumage a cardinal needs to ingest foods with red in them. The pink of a flamingo is variable with the the amount of brine shrimp and blue-green algae in their diet; the more algae relative to crustaceans, the deeper the pink color. Both of these food sources contain carotenoids, and a redder coat may advertise to potential mates a healthier individual.

Male cardinals need to ingest foods with red pigments to get that brilliant color of theirs. Similarly, the better they are at procuring food the redder they'll be. Cardinals molt in the fall and so their spring coloration is due to what their diet consists of in the fall when they're replacing their feathers. All those fall berries (dogwood, barberry, grape, honeysuckle, etc.) provide the pigmentation the males need to say, "Yup, I'm fit and healthy and don't have a darn bit of trouble feeding myself." Males will also feed females as part of their courtship, as if to say, "And I can feed you to."

Other questions that come up for me:
  • Why risk being red when you can just sing? 
  • If you're already red to advertise your fitness, then why also sing? 
  • If they have similar diets, how do females avoid turning red?
  • Given their different colors, what's the difference in predation rates on males vs females?
As I was writing this I thought of an obvious possible explanation for why red is a common pigment among cardinals (and related species in the finch family Fringillidae and grosbeaks, which includes Emberizidae). Members of these two families, as evidenced by their bills, are granivores/frugivores (seed and fruit eaters). Plants advertise when their fruits are ready (which coincides with when the plant is done growing the seed and everything it will need to germinate and begin a new life) by changing colors. Most start green and turn a red, purple, or other color to signify to animals that they can eat the fruits now. The pigments used to signal this are, you guessed it, carotenoids.  Plants readily produce carotenoids to a) protect exposed surfaces from the sun, b) aid in photosynthesis, and c) advertising when fruits are edible. So the birds rely on the plants to tell them when to eat them and the pigments that tell them that to give them their coloration!

Tuesday, April 9, 2013

Bird a Day - House Finch

What: There's been a house finch singing around my property the past couple of weeks. Here's a shot of the male mid-song. The females have the same patterns on their bodies, but as with other finches (Fringillidae family) and grosbeaks (Emberizidae family), they are a drab brown.

Ecological notes: House finches are more recent "introductions" to the eastern US. According to Cornell's Lab of Ornithology's website, All About Birds, the story goes that they were being sold illegally in pet shops in NYC (can't sell migratory song birds under the Migratory Bird Treaty Act of 1918). Fearing prosecution, shop holders released their charges into the wilds of Long Island. They quickly spread out of the city and now cover much of the US (map). In the east, house finches stick more to urban and suburban areas, and in these places have begun replacing the native purple finch, which bears a similar red to the house finch.

Where: My backyard

Monday, April 8, 2013

Bird a day - Titmouse

What: The silver maple has provided me endless entertainment these past couple weeks. We've got a local flock that will swoop through and feed on it for about a half hour before moving on. My room's on the third floor, so I'm more or less "in" the canopy of the tree. While working the other day I snapped some photos of them li'l birdies and will post one species a day this week. The photo I didn't get in time was of a pileated woodpecker! It didn't stay long, which I hope indicates that the tree is in relatively good health.

Bird notes: The little guy above is a male tufted titmouse. They're similar in a lot of ways to black-capped chickadees, but their alarm calls are a much raspier: phweeet phweeet phweeet! and their songs a very sweet "Peter Peter Peter" akin to a cardinal (so much so it has caused much confusion for me). They've got an adorable little crest, slaty blue back, orange sides, and a white belly. There's a pair in this flock.

Where: My backyard

Wednesday, April 3, 2013

Silver maple buds exploded (well, sort of)

What: This is a follow up post to one last Friday, where I've been tracking the developments of the silver maple buds outside my window.

Ecological notes: The weather has cooled off a bit and things are reluctantly marching their way indelibly towards spring. I want to give it a big push!

Taken last week
Where: My backyard

Other notes: The silver maple has been dubbed one of the wonders of the modern world of Latham Ct. While working the other day I spotted an awesome abundance of birds.

Monday, April 1, 2013

The Three Hares (April 2013)

What: Quite a few things have changed in the woods since last month (see list below), but don't show up so much in the video. And it's been a year since I started posting (141 posts so far). Last March was significantly different than this year, with that crazy 80 degree weather that gave us a head start on everything. This time last year most of the shrubs had tiny leaves on them and my yard was carpeted with Scilla (see archived posts from last March here).

Phenology notes from this previous month: 
  • Winooski River is navigable again
  • Great Blue Herons back
  • First amphibian movement of year
  • Killdeer and lots of ducks in water
  • Beaver (retention) pond burst, ice broke after pond drained
  • Scilla (or Siberian squill) is coming up
  • Daylilies and hasta coming up
  • Scarlet cup fungus fruited
  • Flying insects (blow flies on coyote carcass)
  • Dawn chorus is starting (robins first to sing at around 6am followed by cardinals)
  • Geese flying over head en masse
  • Ravens with nesting material, chickadees investigating nest box, woodpeckers drumming
  • Buds swelling on maples, flower buds about to open
  • Ground thawed (no earthworms yet though)
  • Maple sap is buddy
Other notes: Also, in the biggest news in 20 years, Jurassic Park is being released again - in 3D!!