Tuesday, March 30, 2010

Wood Frogs in Amplexus

I went out to the Chippewa River State Trail in Durand today looking to photograph the flowers of the hazelnut.  I've had my eye on one of these shrubs and the buds are just starting to pop.  With the temperature in the 70's this week, it's just a matter of time.

As I walked down the trail, I started hearing a call that sounds like a chuckling duck.  Click here to listen.

When I walked closer to where the sound was coming from - the shallow water in the ditch along the trail, the quacking stopped abruptly.   I stood and waited.

Then one-by-one, little reddish-brown, masked frogs surfaced, floated around and started calling again.  That's when I got my first good look:  Wood Frogs!   

Rana sylvatica

I've seen the adult masked frogs before, but I didn't know much about them.  

The most widely distributed frogs in North America, they've been found as far north as the Arctic.   These diurnal frogs are one of the first to breed in the spring (it happened at 2pm today).   They are known for the explosive timing of their breeding (they get it done in a day or two) and speedy metamorphosis (eggs hatch in three weeks, tadpoles morph into frogs in 6-9 weeks).

Adult wood frogs are able to survive the winter hibernating in forest debris.  Despite the fact that their body freezes (they've become know as "frog-sicles"), when they thaw, they're ready to hop.  

When the weather warms up in early spring, they head to water en masse, call for mates, pair-up, deposit their black eggs in gelatinous masses, then disappear back to the woods.

Today was my lucky day.

I watched wood frogs en masse - in amplexus, their copulatory embrace.  

It was an incredible frenzy of quacking frogs putting the squeeze on each other.

Saturday, March 27, 2010

Do American Robins Find Food by Sight or Sound?

I've been seeing American Robins all winter long, particularly in the Lower Chippewa River bottomlands over by Meridean, Wisconsin.

When I heard the familiar "cheer-a-lee, cheer-i-up, cheer-i-o" song in my yard for the first time this week, I did a double-take... was that a robin?  Singing?  Yes!

The robin is one of a handful of birds most children can identify by sight.  Here in Wisconsin, that may be due to the fact that the American Robin is our state bird - and therefore part of the "state symbols" class taught in most elementary schools.  (I volunteer in the local schools and never cease to be amazed by how little the students know about birds).

Other animals most Wisconsin school kids know:  badger (the official state "animal"), white-tailed deer (the official state "wildlife animal" - a "classification" that's new to me) and the honeybee (the official state insect).   And in case you were curious, the state dance, adopted by the legislature in 1993, is the Polka.

But I digress - back to the robin in my yard...

I sat in my Prius and crept up on the bird.  (Yes, my neighbors probably wonder about the strange person who drives on the lawn).  I wanted to get a photo of a robin pulling up an earthworm.  I had to settle for a robin out on a limb.

As I pulled the Prius back on to my driveway, I found myself wondering:  How do American Robins find worms?

Somewhere in the back of my mind, I recall seeing an image of a robin, tilting its head to the ground.  The caption under it read:  robins listen for earthworms.

Yes?  No?

Unsure, I "googled" and found two answers.  Most of the references on the internet agreed:  robins "look" for earthworms.  Only one reference reported that robins may also use their sense of hearing when hunting worms.

The "looking" reference was the Birds of North America "American Robin monograph #462" by Sallabanks and James (1999):

"When foraging for earthworms, [the robin] uses a combination of "head-cock" and "bill pounce" behavior (Heppner, 1965).  In head-cocking, one eye points towards a spot on the ground, 3-5 cm directly in front of the bird, along the longitudinal axis of the body.  After holding this position a few seconds, the robin rotates and flexes its head to bring the other eye into a similar relationship with the ground.  Bill-pouncing then occurs, whereby the bill is thrust quickly into the ground, presumably at visually detected prey, at the spot where the eyes had been directed."

Montgomerie and Weatherhead reported in How Robins Find Worms  (Anim. Behav., 1997, 54, 143-151) that in a series of controlled experiments, four American robins found buried mealworms in the absence of visual, olfactory and vibrotactile cues, suggesting that robins could use auditory cues to locate the prey.  The authors offered the explanation for the apparent disagreement: 

Heppner’s (1965) carefully conducted experiments showed, in fact, that robins were able to capture earthworms, when they could see them, in the absence of auditory and olfactory cues. He did not directly test whether they could use these other cues in the absence of visual cues.

So... next time you look at the lawn and see a robin cocking his head, he may be looking... or listening... or looking and listening for a worm.

Wednesday, March 24, 2010

Getting Ready for Bluebird Season

 Bluebirds at a nest box in Tarrant Park, Summer 2009

The Durand area has the largest concentration (more than 25%) of remnant prairie habitat in the badger state - perfect habitat for Eastern Bluebirds.

I can't seem to go anywhere without seeing bluebirds these days.  They're on the utility wires along the roadsides.  They're singing in the trees.  And they're flying along the roadsides.

I've been seeing bluebird nest boxes everywhere too.  That's good news, and unfortunately, sometimes, bad news.

It's good that landowners want to see bluebirds nesting on their property.  The bad news comes when well-meaning people don't do it "right,"  unaware that they may be contributing to bluebird nesting failures.

How's that?

Too many boxes are not properly designed and installed in the "wrong" places, the "wrong" way.  Many are never monitored and seldom maintained.

There actually is a "right" way to do it in Wisconsin.  It's not a matter of personal opinion, the Bluebird Restoration Association of Wisconsin has the scientific data to prove it.  For up-to-date advice on how to be a good bluebird landlord, take a look at their brochures - click here.

The following are some photos of "problem" bluebird boxes:

On a tree in the woods, 10-feet off the ground, in the woods at Silver Birch Park.  Wrong habitat (bluebirds prefer open, prairie-like habitat, ie lawns), easy access for predators (snakes and raccoons climb trees) and too high up to monitor.

Here's one of the bluebird boxes at the entrance to Silver Birch Park - on a 4x4 pole (easy access for predators).  The box design is not "current" - the hole is too high and the vents are too big.   It faces the wrong direction (west) and it hasn't been maintained or monitored.

This "Peterson" box is a good one.  The roadside location is fine.  The problem with this scenario is installation.  The utility pole provides easy access for predators, and it's too low to the ground.

I found this white box out on the prairie high up on a tree.  The box design (dimensions, hole size, color and construction material -  1/4" plywood) and installation will likely result in nesting failure.   And it doesn't open for monitoring and cleaning. 

I found a number of these paired boxes on RR107 on the way to Meridean.  Years ago, bluebird experts experimented with this new strategy (pairing boxes) to increase nesting success.  It didn't work.  Even if had, these boxes need design improvements, metal poles and maintenance.

And here's a cute little critter I found in a nest box over by the cemetery: 

It's important to clean out the nests after each brood has fledged, and before the new season begins.  I found this box full of bird droppings - an indication that the birds have been using the box as an overnight roost this winter.

For more information on how to select, construct, install, maintain and monitor a nest box appropriate for your property, take a look at Homes for Birds and The Expert's Guide to Backyard Birdfeeding.

Tuesday, March 23, 2010

Lake City Eagles, Gulls and Ducks

I crossed the Mississippi River to look for migrating birds this afternoon.  I found them in Lake City.

 Riverfront Park at Reads Landing, MN - looking south on the flooded Upper Mississippi River
I stopped along the way at all the usual places.  We didn't see many birds at Reads Landing -  only a flock of Cedar Waxwings feasting on the insects swarming in the cottonwoods.  No ice.  No eagles.  No waterfowl. 

Further up Highway 61, the Mississippi was still covered with a very thin sheet of gray ice.  I couldn't resist stopping to look for eagles. 

 A tourist looking north at eagles on the ice on the Upper Mississippi River north of Reads Landing

First stop: the Lake Pepin sign.  Looking north, we spotted rows of eagles sitting on the ice, loafing and fishing from the holes left by ice-fishermen.

Camp Lacupolis:  my first of the season pair of Common Mergansers.  The minute I spotted them, they dove, and bobbed back to the surface too far away to photograph.

Lake City Sportsman's Club:  Herring Gulls and a lone Ring-billed.

 Ring-billed Gull in Breeding Plumage

The jetty at Lake City Marina:  Dozens of Bald Eagles and gulls on the ice flows.  Worth the walk down to the light.

A pair of Lesser Scaup at Lake City's Ohuta Park

Ohuta Park (Park and Chestnut Streets):  A Bald Eagle (a sad story), tangled up in fishing line - clearly starving, but still flying short distances - I contacted the National Eagle Center;  and a raft of waterfowl (Red-headed ducks, Lesser Scaup and American Coots).

Before we headed home, we stopped to see what's up at Colvill Park in Redwing.   It was flooded!

No eagles.  No waterfowl.   Just a lot of very fast moving water.

A sign at the exit says the park will be closed Wednesday.   Flood waters will crest later this week.

Monday, March 22, 2010

Hooded Mergansers and Tundra Swans

Late this afternoon when the temperature hit 55, we headed to the Lower Chippewa River for a stroll, and then down to Meridean to see if it was warm enough for the insects to be out and about.

Along the Chippewa River State Trail by County M, I heard a familiar sound "like dragging your finger over a well-inflated balloon" (according to Amphibians of Wisconsin).   I stopped and look for the frog that created it.  I scanned the wetlands, but the frog was invisible.  Try as I did, I could not spot it.

While I was looking down, I heard the faint calls of Tundra Swans over head.  I gave up on finding the frog and looked up.  I looked, and looked.  I couldn't see them either.

Then I spotted a faint silver flash as a skein of 30 or more high-flying swans turned - and their feathers caught the sun.  There they were.  Way, way up there.  Too high and too far away for a photo. 

Further up the road on the way to Meridean we were surprised to see our favorite oxbow - empty of waterfowl.  No ducks.  No geese.  What's up?

I stopped wondering when I spotted a Canada Goose, dead on a patch of ice floating near the shore.

Just south of Meridean, we stopped on a little bridge to check out 2 ducks swimming away towards the river.  I grabbed my binoculars and got a good look before they disappeared in the flooded forest.   Hooded Mergansers!

The smallest of the three mergansers found in Wisconsin, the drake is a strikingly handsome black and white bird with a fan-shaped, crested head, rusty brown flanks and narrow, black serrated bill.

Saturday, March 20, 2010

Back to Normal Weather

After an unseasonably warm week, March temperatures are back (30-degrees cooler).  But we haven't had any precipitation all month.  In fact, if the dry weather continues, this could set a record for the driest March ever.

It was chilly, but the sun was shining.

Saturday is our day to shop in Eau Claire, and on the way, take a spin through one of the most species-diverse locations in Wisconsin -  the little dot on the map along the Lower Chippewa River known as Meridean (no, they didn't mis-spell me-rid-i-an, it's pronounced merry-dean).


We didn't get very far on State Road 25 before I spotted another early migrant, our first-of-the-year Killdeers.

A pair of them was foraging along the road, next to a recently plowed potato field.   I cringe when I think of all the chemical-laden food these birds eat.

It won't be long before these fields will be marked with little red  "peligro - poison" signs when they start laying down this year's pesticide layers.  A neighbor explained the reason for the signs, and said:  I only eat organic vegetables.   I think about that conversation every time I drive by.

I continued north on State Rd 25 and turned on to County M.   Because of the change in temperature, I had to drive with the windows up and the seat heater "on."  Heated seats were not on my "gotta have it" list when I was shopping for a new car.  But that and the leather seats came with only Prius left on the lot.  My choice was buy it or miss-out on the "cash for clunkers" rebate.

I want to believe that I bought a safe car, and all the to-do about the run-away Priuses and Toyota "quality control issues" will dissipate with time.   I still worry about my "investment," but for the most part, I really like my Prius.  Every time I drive to Eau Claire, I get ~60 MPGs.  Amazing.

But unlike our outings earlier this week, we didn't spot any insects, and only a couple of squirrels, crows and bald eagles along the flooded river bottoms. 

When we pulled in to Meridean, I spotted a small flock of Black-capped Chickadees flitting from tree to tree.  I stopped and pulled out my iPod.  I tuned it in to the Chickadee song on Bird Jam and turned up the volume on the car radio.  It was as if my big black Prius had been transformed into a giant chickadee - and the little flock united in an effort  to drive us away.

I snapped a few photos, then let them go back to looking for food.

We took in a movie - the new Jude Law flick - Repo Men.  To say it is violent - is an understatement.  Interesting premise.  The twist at the end caught both of us off guard.  Rent it.

We picked up groceries then headed back through Meridean around 5:30.    Along the way, we spotted two pairs of Canada Geese establishing territories at opposite sides of our favorite oxbow, a pair of mallards and our first Wood Ducks of the year.

Our biggest surprise came further down the road.  We stopped to look at Eastern Bluebirds - and a Barred Owl flew right in front of the car, landing in a nearby tree!  

 "Who-cooks-for-you?  Who-Cooks-for-you-all?"

Friday, March 19, 2010

Snow Mold

I did a double-take when I looked at the melting snow bank along the roadside today.   It wasn't snow.  It looked like a giant tightly-woven spider web.

Tom knew what it was:  snow mold!

It grows on grasses covered by piles of snow, he said.  And its spores are one of the causes of seasonal allergies in the spring.

I was surprised that he knew about this lawn fungus (Typhula).  (He doesn't believe in lawns).

How'd you know about this?  I asked.

He saw a story about it on WCCO-TV this week.

The cure is simple:   exposure to the elements.  The sun to warm it up.  The wind to dry it out.

Thursday, March 18, 2010

A Sparrow and a Comma

Another 60º day and another FOY (first-of-the-year) bird and butterfly.

I was sitting in the Prius with Tom, listening to Sandhill Cranes bugling in the corn fields along the Lower Chippewa River at Meridean.  I heard a familiar song that I hadn't heard in months.  I had to pause.

Who was it?  Click on this link to listen.

I had to pull out my iPod and connect it to my Prius audio system so I could confirm it by listening to the song on my BirdJam playlist.

While I was listening to my iPod through the car radio, this little Song Sparrow flew right over and perched on the barbed wire fence across from me.  He stared at my car and seemed puzzled by the very loud Song Sparrow song emanating from it.

I'd forgotten how much fun it was to drive the stealth Prius with the windows down.  It is the best vehicle for watching, listening to and photographing birds (butterflies and other wildlife).  When I put my foot on the brake, the engine shuts off.  No noise.  No shake.  

Despite all the hoopla about the brakes, today's wildlife expedition was a reminder of why I bought a Prius.  I drove 42 miles and I got 67 MPG.  What a great car!

I had to laugh at my experiences with butterflies and moths today.  I'd see one and stop;  put the Prius in "park;" then hop out.  The minute I got out of the car, the butterflies would fly off.  

However, if I stayed in the car, they ignored me.


I wasn't sure at first what this species was.  When I got home and processed my photos, I saw the distinctive "comma" on the under-wing:  an Eastern Comma.


I spotted an infant moth, an eastern comma and several mourning cloaks.

The Eastern Comma and the Mourning Cloak both over-winter as adults by hibernating.  Although they may also migrate, the Mourning Cloaks are known for their roaming.  Both are often seen out on warm days in late winter and early spring.  

The overwintering Comma adults will fly and lay eggs in the spring until April.   The larval food plants are wood nettles, false nettles, hops and American elm.  The adults feed on rotting fruit and tree sap.   Look for both feeding at sapsucker holes in March.

Adult Mourning Cloaks prefer tree sap - especially oaks - and they feed like a nuthatch - head down on tree trunks.  

Their larval plants are willows, American elm, hackberry, paper birch, cottonwood and aspen.  Adults will encircle twigs with eggs.  Mourning Cloak caterpillars hatch and share a communal web, feeding on young leaves.

Wednesday, March 17, 2010

The Prius Recall Notice

It arrived in the mail today:


click on the image to read the fine print

I've taken my Prius in for the computer software update.

Now I'm planning a road trip.

American Hazelnuts - Found!

The Lower Chippewa River valley was covered by a damp blanket of fog when I got up this morning.  Around noon it looked like it would burn off, so I hopped into the Prius and headed north to the Chippewa River State Trail.  I just had to find the hazelnut today.

I got as far as the Maxville School when I saw a skein of Sandhill Cranes fly over head.  A dozen buglers.  I stopped at the school to tell the kids to get outside and watch!  Turns out they'd heard (but didn't see) them earlier this morning.

I got back in the car and continued past the farm fields into greater downtown Durand (population 1,968).  I was just the sewage treatment plant when I noticed a big dark bird soaring up ahead.  It wasn't a Bald Eagle - it was the first of the year (FOY 2010) Turkey Vulture!

By the time we got to Tarrant Park the fog had burned off and the sun was shining.


The trees and willow shrubs were full of Red-wing Blackbird males, alternately flocking (hiding their red shoulders) and then singing (flashing their red) to stake out the best territory in the marshes along side the trail.  

Where were those hazelnut shrubs - full of filberts - that I photographed last fall?  How is it that I could find a cocoon in the woods, but I just can't see a hazelnut shrub along the trail?  

I finally found one on the walk back to the parking lot.  What caught my attention was the solitary empty nut case hanging on the more familiar hairy twig.

The trick now will be to come back on the "right" day - when the buds burst.

The rest of our walk was uneventful.  We pulled in to the driveway at our little farmhouse in the town of Nelson and were greeted with the sight of our National Bird, soaring overhead.  We watched until it landed across the street, right outside my kitchen window.

As I sat down at the kitchen table and started to process my digital images, I looked out the window towards the river - and realized the prairie in the Chippewa River bottoms was on fire!  I could see the white smoke above the tree line.  

I have something to look forward to now:  prairie grasses and wildflowers (and no weeds) blooming in May!

Tuesday, March 16, 2010

Contrails and Weather

With all the warm weather lately, I've been noticing all the jets in the sky and their contrails.  

While I've used the term "contrails" before and I know what they look like, I didn't know the etymology.  So I went to my trusty Webster's to find the definition:  "white trail of condensed water vapor that sometimes forms in the wake of an aircraft."

When warm and humid jet exhaust hits cold air, water condenses.   Think of breathing on a cold winter day when your breath forms a visible cloud.

Why I don't notice contrails all the time?  (Am I not paying attention?) 

I went to "google" and hit the first link which took me to the Weather Service.  Hmmm.  There must be a "weather" connection here.  Sure enough, I found the connection towards the bottom of the page:

"... sailors have known for some time to look specifically at the patterns and persistence of jet contrails for weather forecasting. On days where the contrails disappear quickly or don't even form, they can expect continuing good weather, while on days where they persist, a change in the weather pattern may be expected."

If this is true, our weather is due to change.

What's the forecast?  Rain, slush and colder weather over the weekend.

Check out this website for more information.

Monday, March 15, 2010

Tent Caterpillar Egg Masses

The Ides of March brought another 60º day in west-central Wisconsin.

I spent the morning on the Lower Chippewa River State Trail, looking for two things I'd spotted last fall: a cocoon and a hazelnut shrub.

I was distracted by the enthusiastic spring songs of Northern Cardinals and Eastern Bluebirds, the raucous crows, the horse-like whinny of American Robins, the bugling Sandhill Cranes and the tat-tat-tat-tat of drumming woodpeckers.

I stopped to photograph a boxelder tree bud and was startled by the splash of what I thought was water on my hand.

It was sap, dripping from a twig that had been broken off by browsing deer.  Boxelders are in the maple family and this is sugar bush season in Wisconsin.  I've often wondered what boxelder sap tastes like - the bugs smell so vile.  I was hesitant, expecting the worst.  But I tried it.  It tasted like water with a hint of sugar - not bad at all.
I actually found the silk moth cocoon, 2 miles from the Tarrant Park parking lost.  I was amazed it was still there, and that I remembered exactly where.  On the walk back to the parking lot, I spotted another one.  And to think all these years, I've never once spotted a cocoon in the wild.

The woolly bear caterpillar were out and about too.  Unfortunately the bike trail was littered with their squished carcasses.

And you'd think finding the hazelnut shrub would be relatively easy.  It wasn't.  I still haven't found it.

However, I did see something I'd never noticed before:  tent caterpillar eggs.  Female moths can lay up to a thousand or so eggs in tight clusters and before they're done,  they coat the egg mass with a waterproof substance.  These insects spend most of their life-cycle as eggs. 

They will be hatching soon.

Sunday, March 14, 2010

A Day of Firsts

The sun came out and the sky turned blue around noon.   The temperature hit a record 66º.

After a week of chilly gray weather, it was as though someone flipped the "What Season Is It?" switch from "winter" to "spring."  Ironic we should have such great weather on the day we set the clocks ahead one hour.

A wonderful welcome to daylight savings time!

The sky was full of bugling Sandhill Cranes, aerial duets of Bald Eagles, and the conk-ker-ees of Red-winged Blackbirds.

I spotted a huge turtle, looking dazed as it pushed through the muck along the Chippewa River State Trail a mile north of Tarrant Park in Durand.  

Willow buds were bursting full of silvery pussy toes and wine-red skunk cabbage flowers pushed though the muck on both sides of the trail.

Winter Crane Flies were swarming all over the Little Bear Creek bridge.  These harmless diptera (true flies) are often seen on warm, sunny winter days.  The short-lived adults live to breed.  They're snack food for birds, amphibians, spiders and other insects.  The larvae live in the leaf litter and help break it down into soil.

On the way back to the parking lot, a surprise find...

A dead mouse, just down the trail from where I turned around.  How I missed it was a mystery.  It wasn't "fresh," but it hadn't been mauled.  Maybe a fox or a raptor dropped it?

Later in the afternoon, we headed over to Silver Birch County Park to check out the tree buds.  I slammed on the brakes when I spotted my first of the year mourning cloak butterfly flitting along side the still-frozen lake.

No doubt about, today was the first day of spring 2010.