Friday, December 31, 2010

Inside the lodge

Thanks to Carl in VA for this BBC link to the secret lives of beavers inside the lodge.

Check it out.

Thursday, December 30, 2010

Curiosity kills the Cam

Thought I'd better check my blogroll before posting this one, and sure enough ornithologist John Carlson had just posted on BBC's latest polar bear film.

John knows a lot about ice and cold so be sure to check out Prairie Ice for links to this very nifty camera trapping footage.

(And thanks, Nik, for the heads-up.)

Tuesday, December 28, 2010

A good camera trapping story



Cougar Magic recommended "Ambushed on the Jaguar Trail" to me last summer, and my daughter gave me a copy for Christmas.

It is subtitled "Hidden cameras on the Mexican Border", so of course I read it in two nights.

The authors, Jack and Anna Mary Childs are a retired land surveyor and school teacher whose pastime of tracking mountain lions with mules and lion dogs led to the chance discovery of a jaguar on a hot August day in 1996.

At the time jags in the American southwest were thought to be a memory of the past, but this and another sighting kick-started a joint venture by Arizona and New Mexico Fish and Game authorities to investigate the status of the big cat.

The Childs got involved and became committed camera trappers.

This book is a good read about using camera traps to learn about jaguars, and contains lots of good natural history about southwestern wildlife.

It also captures the fascination and thrills of camera trapping, and is a testimony to what we can learn from a harmless but mentally and physically invigorating hobby.

My hat is off to the Childs for their commitment to nature and their contribution to wildlife education and conservation.

There aren't many books about camera trapping, so you won't go broke collecting them.

Add this one to your collection.

Wednesday, December 22, 2010

Decoying acorn woodpeckers


Can you fool acorn woodpeckers to use a fakey-looking granary?

If you don't know about woodpecker granaries  -- they are the pinnacle of the acorn woodpeckers craft -- live or dead trees and limbs riddled with holes stuffed with acorns.

They are such curiosities that outdoorsy Californians snatch up fallen chunks to decorate their gardens and homes.

When there's a shortage of granaries the woodpeckers get in trouble.

I have plenty of oaks around my house, but no woodpecker granary.

Noisy peckers visit, but fly off with their booty.

I sometimes awake in the dead of night wondering -- would the local peckers adopt a man-made granary?

How picky are they about the age and density of the wood?

How high would I have to hang the thing?

In November I finally got the lead out and built a fake woodpecker granary.

For a pilot test I drilled holes of 4 sizes in a 4-foot length of dead canyon live oak.

Then I put the granddaughters to work collecting acorns -- tanbark oak, Canyon live oak, and black oak.

Stuffed the holes.

Hung it near the house on a black oak.

The camera trap took 44 photos in 8 days and then the batteries died.

Ignorant of the power failure and with hopes periodically kindled by the endearing rukka-rukka of calling peckers, I waited another 20 days.

Only one woodpecker was photographed, and only barely as you can see.

There may have been others triggering the camera, but if so, they stuck to the other side of the log.

I'll keep that in mind the next time I set the camera.

Monday, December 20, 2010

Friendly face flies of fall

The face flies of summer -- black-tailed deer at Chimineas in September

A warm spell recently summoned overwintering flies from the woodwork, and for several days the redhead wielded the fly swatter with deadly vengeance.  

The autumnal house fly is often found to be the face fly (Musca autumnalis), that nemesis of cattle whose exquisitely designed mouthparts sponge up secretions of eyes, noses, mouths, and wounds, and then stimulate further secretion with rasping prestomal teeth.  

The face fly evolved with the herding ungulates of Eurasia, but not until 1952 did it make its appearance in North America.

Somehow they missed the boat several hundred years ago when the Spaniards brought livestock to the New World. 

But they found everything they needed, multiplied, went west, and reached the golden state in the 1960s.

Face flies have an intimate relationship with eyeworms.

Eurasian and African face flies of several species are hosts of at least a dozen species of these parasitic nematodes of the genus Thelazia.

Adult eyeworms live under the eyelids and in the tear ducts of ungulates.

They lay their eggs in the lachrymal secretions, and the flies lap them up as they feed. 

After hatching the worms develop in the flies' fat bodies, and when about half grown they transfer back to eyeballs, where they cause anything from mild inflammation to conjunctavitus, and even blindness.  

Though the newly arrived face flies were not carrying eyeworms, there happens to be one species of eyeworm native to North America.

Guess where it lives?

Hint: The scientific name is Thelazia californiensis.

Our native eyeworm infects deer, jackrabbits, and coyotes, and sometimes livestock, dogs, and cats.

There are even a few cases of human infection.

Entomologists had long believed that the canyon fly (Fannia benjamini) was the California eyeworm's host, but it really didn't matter because our state eyeworm was economically inconsequential.

That quickly changed when word got out that the face fly was headed west, where wet noses, rolling eyeballs, and drooling lips abound.

If the face fly and our native eyeworm were compatible California's livestock could be in trouble.

Cattlemen started to worry and the state's economic entomologists began looking into the likelhood of an eyeworm epidemic. 

The entomologists examined seventy species of arthropods associated with native mammals, but only a small fraction of canyon flies harbored eyeworm.

Then it was discovered that canyon flies were actually three separate species, only one of which -- an uncommon and apparently undescribed species was the true host of the eyeworm. 

There was a flurry of fly collecting to start a laboratory colony.

"Some dexterity with a net is needed to catch any of these flies . . . , but the vector species seems to be particularly elusive, judging from its behavior in the laboratory."

So noted the investigators, but they prevailed and the elusive new species of fly was bred in the laboratory where it consistently infected domestic rabbits.



With a ready supply of eyeworms and their eggs, the entomologists fed the parasites to face flies with deft and caring tenderness.

The infections didn't take.

Our native eyeworm is highly host specific. In other words, face flies and domestic livestock are not suitable hosts of the California eyeworm. 

Neither are people, most of the time.

But take note dear friends.  Eyeworms will scare away a date faster than any amount of spinach in your smile. 

The take home message is this: "Don't joke about flies or make fun of entomologists."
   

Note: In the absence of voucher specimens I am not sure of the identity of these flies, and for now I will assume they are the common face fly (Musca autumnalis), which winters in homes and buildings.


References

Olroyd, H. 1964. The natural history of flies. Weidenfeld and Nicholson, London.

Weinmann, C.J. et al., 1974. Eyeworms and face flies in California. California Agriculture, November, pp. 4-5.
  

Friday, December 17, 2010

Drowning in beer



It's no secret that I pick up trail trash, and beer and power drink cans are the items most commonly discarded on my regular beat -- the flume trail. 

It seems an increasing number of flume walkers quench their thirst with pricey beverages instead of  water. 

Yesterday I found a 16-ounce can of MGD tucked into the duff next to the trail.

It was half full and as I drained the foul-smelling liquor -- no, not into my mouth -- something soggy blocked the opening.

A mass of black fur, a tiny foot and a shrew-like tail. 

I carefully stuffed my stinky can with its treasure into the outside pocket of my rucksack and continued my late afternoon hike.

Back at my workbench I opened the can and found the marinating contents to be three shrews, a carabid beetle, and a millipede.   




The strolling beer-drinker had set the perfect shrew trap, a smooth-sided pitfall that attracts arthropods.

The shrews stunk, but they were still intact. 

So I doused them with alcohol, inspected their teeth with my dissecting scope, and keyed them out as Trowbridge shrews (Sorex trowbridgii).

This western species eats Douglas fir seeds, in addition to usual earthworms and insects, and few live long enough to grow the brown summer coat of their second year.  




Pleased with my finding, I retired to the house.

As I passed through the kitchen I smelled the rotten shrews.

"I'll wash up in a minute . . . those shrews had a powerful stench."

"That's not what you're smelling", said the redhead -- "We're having sauerkraut with pork chops tonight".

Saturday, December 11, 2010

Outlaw no more



You get road-respect when you drive a 28-year-old junker that roars, lurches, and looks like an accident waiting to happen.

I bought the green machine from an old friend for $500.



"What's the little pillow for", I asked.

"Don't throw it away", he warned.

"You'll need it unless you want the seat spring to tear you a new you-know-what."

He also gave me a long list of maintenance notes, jotted on a used envelope from the Model T Ford Club of America.




 "High beam mostly does not work -- probably switch.
"Automatic choke does not work.
"Horn needs new pigtail or shim or part from Jeff's
"Heater fan does not work -- probably motor -- remove -- check -- have another from Jeff's truck.
"Running down road with relaxed throttle then giving gas usually makes truck buck. Has always done that -- probably carburetor.
"Sometimes comes to stop sign then doesn't want to idle -- has always self fixed soon after.
"Etc.

Okay, it wasn't perfect, but let's face it, heaters are for wusses.

Yes, the windshield fogs up in cold weather, but you know what? Crank down the window and the problem is gone.

The roof leaked too, but a little caulking fixed that.

Now it looks like the great speckled bird once perched there.

But who cares, it's served me well, and the neighbors always know when I'm coming and going.

I've dragged logs with it, and hauled tons of supplies, rock, lumber and firewood in it.

When I lob a flitch of manzanita into the bed, I don't worry about the paint job.

And Fred loves it. Drop the tail gate and he comes running for a ride.  Recently he's taken to napping in the cab.

"Drive a car that looks like a wreck and feller drivers give you respect."

Did Johnny Cash write those words?

Well, that's what I've learned.

Old folks give me a wide berth, yield the right-of-way even when it's theirs, and show grace and forbearance when I'm straining up a hill at 35 mph.

And if some punk passes me in a hurry,  I rock in the seat like I can't make it to the top without human momentum.

But my friends, there's trouble in River City.

The green machine didn't pass smog inspection.

"I'm sorry", apologized the inspector, " but your car's now classified as a Gross Polluter".

The green machine was declared an outlaw, which means I had to get the mechanical deficiencies corrected and have it reinspected at a Gold Shield Smog Inspection station.

If it didn't pass reinspection. . . . well . . . .  you know what that means. (Damn, I'm choking up.)

I felt like a criminal when I broke the news to the redhead.

"You're a gross polluter!?", she gasped with revulsion and rolled her eyes.  

The needful was done, I paid the mechanic, and with that the green machine's value doubled.

He handed me the keys and I noticed that old greenie had a certain soft glow, like a ripe Granny Smith apple.

"You know, I haven't driven it yet, but it even looks better on the outside."

"That's because it feels better", my mechanic sympathized.

I haven't yet adjusted to the loss of the roar, and the new sound isn't exactly a purr.

In fact it sounds more like a geckering binturong.

But I'm feeling good. The green machine is an outlaw no more.




Nota bene: If you really want to know about geckering binturongs see: Wemmer, C. and J. Murtaugh. 1981. Copulatory behavior and reproduction in the binturong, Arctictis binturong. J. Mamm, 62:342-352.

Thursday, December 9, 2010

Ring around the collar



You can't fully appreciate it from the photo, but Stinkarella has a ring around the collar.

I pulled a couple of cameras today, and this spotted skunk made a couple of appearances on an overgrown logging road.

In all of the photos its nose is in the ground and its neck is stained.

I've seen the dirty neck before in these little Butte County stinkers.

Rubbing the neck on smelly substances, or self-anointing is a common trait among carnivores and a familiar and distressing habit of dogs.

That's how stinky got the ring around the collar, I believe.

There are more theories than data about the function of self-anointing.

One prevalent idea is that it disguises the owner's scent.

Somehow I find this hard to believe in skunks.

Tuesday, December 7, 2010

Commuting in civilized nature



If your ancestral breeding ground is the engineering wonder known as the Butte Creek Flume, reaching the pool of conjugal bliss can be a dangerous odyssey.

I'm speaking of Sierra newts (Taricha torosa sierrae), which my observations indicate are not content to just drop into the flume when they find it.

Instead they follow the path ridden and trodden by bikers, hikers, dog walkers, and galloping dogs -- most of whom pay no regard to pedestrians like banana slugs and newts.

At some point of course the survivors find the pool of choice.

I stumbled into this newt today shortly after it ascended the on-ramp to the catwalk, and I watched as it newt-walked unerringly to the far side -- a span of 20 feet.

One of many catwalks on the flume.

Nonetheless I found it worrisome.

The path wasn't straight and the spaces in the expanded metal were big enough for the newt to fall through.


If it fell off the catwalk it wouldn't be the first time.

A few months ago I stumbled into a bloody gentleman here.

He was about my age, and had stepped off while adjusting his wrist watch.

Just stepped into space, lost his grip on the handrail, and slid down the gunnite wall below, de-barking elbows and fingertips along the way.

"I'm okay", he insisted when I offered to get the truck, "but I'll feel it tomorrow morning."

I haven't seen him since, which can mean only one thing: his wife grounded him.

The gunnite wall below the catwalk.
It could happen to me.

My camera trapping ventures would be restricted thereafter to a 50 foot radius of the house.

I studied Sally again, who was still on course with 15 feet to go.

The fall wouldn't be fatal for a salamander either, but . . . .

I picked it up anyway, crossed the bridge, and released it on the other side.

Sally didn't miss a beat, and just kept going in the same direction.

Sunday, December 5, 2010

Awesome athletes

The air-born phase of the broad jump.
Taut-muscled athletes -- yes, we have them at the Chimineas Ranch.

Sometimes we see them in training late at night.

It's all track and field events -- no team sports.

It was our good fortune to capture a few images of one of these athletes practicing the broad jump.

Scope out this athlete's form -- the extended whiskers, erect ears, flexed forepaws and symmetrically poised hind feet.

The straight back and gracefully arched tail show the ballistic perfection of the bullet--shaped body.

This Olympian demonstrates gold metal form.

The launching or propulsive phase of the broad jump (feet still on the ground).

Tuesday, November 30, 2010

A nondescript spring

Raccoon hand-jiving for aquatic life

In August I set a camera trap at a shady nondescript spring a few miles from my house.

It's in a steep-sided defile, and it's choked with dead wood and fallen trees.

We looked like poodles wearing galoshes as we high-stepped over the sticks.

The bed of the seepage was filled with rock rubble, and the only place I could drive the stake was into the bank, looking down -- not a preferred vantage point.

I didn't expect any surprises, figuring we could count on lots of gray squirrels, wood rats, and deer mice.

But you never know for sure what'll turn up in a month's time.

The vociferous Douglas squirrel or chickaree

The raccoon was the only carnivore that showed, and it was clearly grubbing for aquatic delectables.

Both chickaree and gray squirrel came to drink.



Deer mice were everywhere and used the sticks as overpasses.

And the wood rats were no shows.

  




Steller jay, spotted towhee, and fox sparrow(? tell me if I'm wrong) tanked up from the same perch
.








What I didn't notice right away was an incidental sally meditating by a riffle.





The peaceful amphibian was the Sierran subspecies of Eschscholtz's salamander (Ensatina eschscholtzii platensis) waiting for a passing insect. 

As the mice skipped about and triggered the camera Sally's image was captured several times on two nights.

She was always there peering into the water. 
  
Then the camera snapped her in a different position.

She actually moved, and I knew she wasn't a gumby toy.



Thanks to JK of Camera Trapping Campus for confirming the Sally ID.

Monday, November 29, 2010

You tell me


It was the day before Thanksgiving.

While cutting firewood I had stumbled upon the other three screech owl boxes I had lovingly built, and I started to wonder about the fourth one.

I hadn't checked on it since I hung it up, and this was the condition I found it in.

Would anyone care to reconstruct the story for me based on the visible evidence?

Sunday, November 28, 2010

A True Tale of a Ringtail

Photo by Michael M. Collins

Friday's post drew out the true-life testimonies of two CTC readers -- convincing proof once again that Ringtail isn't a fairy tale fabrication.

Entomologist Michael Collins' comment brought back fond memories of collecting days with some mutual friends and mentors, and it came with the photographic proof seen above.

Here's his tale . . .

"I had in 1988 a humorous encounter with a ringtail while blacklighting near Lake Pena Blanca in the Atascosa Mts. west of Nogales AZ . 
It was a moon-less night, best for blacklighting for saturniid moths (my specialty), and the world was very dark beyond the blue glow of the light and sheet. 
Nevertheless, I thought I saw a shape quickly moving through the brush, right at the edge of the steep rocky cliff near which I had set up my light.
I began shooting in the direction of the movement with my Nikon film camera, not sure I had recorded anything. 
I did notice that several large sphinx moths began disappearing from the ground around the sheet! 
On getting the prints back a week later I first admired the thick black-and-white tail that I captured exiting the frame, flipped through the prints, and found I had by good luck caught a ringtail in decent focus, who was in turn focused on taking the best moth specimens that were coming in. 
These neat little animals are probably common in the Yuba River canyon near my home in Nevada City, where 49er prospectors called them "miner's cats", but I have never seen one in the wild in all this time in California.
The Arizona sighting was a rare and special treat."

If it's scientific exploration in the field that turns you buy Dr Collins' memoir -- Moth Catcher: An Evolutionist's Journey Through Canyon And Pass, and check other interesting titles listed in the University of Nevada Press's  Holiday Sale (click on Sale). The prices are right!

And thank you, Michael, for sharing that evocative memory.

Friday, November 26, 2010

Even camera trappers get the blues

In the canyons, the deep deep canyons, the ringtail roars tonight.

A wishful image spurs us on -- Ringtail's lithe form scaling the moonlit rocks like spider woman in buff-colored tights.

She lures us hither and yon searching for the right habitat and a dried token of her presence -- a hope-sustaining turd.

But in truth we wouldn't know one if we found it.

We've searched the literature and poured over museum records for clues.

Damn it, we've looked in all the right places.

We camera trapped rimrock, stony recesses, and rock piles. No ringtails.

We camera trapped the same kinds of places near water. No ringtails.

We learned that Texas ringtails eat juniper berries in winter. Now we're cam-trapping the juniper woodlands.

The elusive quarry inevitably comes up during Chimineas rendezvous.

On some some dirt road to nowhere it's -- "Hey look at those cliffs over there -- looks like ringtail habitat".

It comes up during happy hour.
"I swear, they're all over the place in Butte and Plumas County." I saw a dead one on Rt 70 last week, and even the kid at my local hardware store knows their favorite bait."
"Whats that?' Craig rises to the bait.
"Strawberry jam." 
"We're using all fruit jam."
"No wonder we're not having any luck."
The team collects the camera traps the week before Random Truth and I arrive.

They scope out the pictures in the field, which is one of camera trapping's simple pleasures.

Back at the lab they download the memory sticks and view the photos again on the computer to see if they missed anything.

When the photos are found wanting of ringtails Craig slides into a blue funk.

Fortunately, he's a busy man and the blues don't last long.

A few days layer we all meet and our 3-day camera trapping session begins.

These are generally convivial reunions, but we rarely have time time to set all the cams.

When we part ways Craig is jazzed to cast off with Todd and Heather to set the remaining ones.

After the last session he sent me this email.
"Lucky we didn't try to get to Hunt Spring when you were out here. It was a hell of a hike and the canyon with the spring was so steep and choked with brush, we couldn't get down to it. I might try to get down there in cooler weather.
 As it was, we left the truck at about 2:30 in the afternoon and got back at close to 8:00 pm.  We hiked the last portion in darkness.  It was still very hot (mid-90's) this past week and we brought plenty of water. 
However, it was still a strenuous hike and Todd ended up overheating and upchucking.  I felt bad for him but we sat in the shade until he felt better and we headed back to the truck. 
We actually set the cam in a very interesting spot.  We found a large expanse of rock outcrops overlooking Gypsum Canyon and surrounded by chamise scrub.  It's similar to the spot where we got Spilogale last time.  I am encouraged because the canyon it overlook is more mesic that most of the stuff on Chimineas proper.  I could see sycamores growing in the canyon bottom.  It looked ideal for ringtails but the proof is in the pudding.  Let's wait and see what we get."
I have to admire those plucky guys. Nothing like cooky-tossing dedication.  And I should mention that Todd's the one who hauls the pack.

To hither an yon


We checked Craig's set when we arrived at the ranch.

An impenetrable expanse of chamise blocked their access to Hunt Spring, so they set the cam on a beautiful outcrop.

I would have selected the same place.

Craig at the set above Hunt Spring

But only two critters mugged for the camera -- right on that boulder in front of Craig.



And ringtail wasn't one of them.


Sunday, November 21, 2010

The death of Big Sally



The doomed California giant salamanderDicamptodon ensatus, was photographed in the jaws of a raccoon on October 18th, 11:48 PM.

The location on a trail in Marin County wasn't far from a steep year-round creek with prominent step pools.

Habitat: coastal mixed confer and deciduous forest. Lots of lichen and mossy trunks, and the bracing scent of bay laurel.

I regard any species of Dicamptodon with animistic reverence, not just for their size -- up to a foot, but for their bark, bite, and ruggedly handsome good looks. Not to mention their penchant for gobbling banana slugs, small snakes, shrews and mice.

Dicamptodon is an icon of our moist coastal forests and an indicator of watershed health.

The number and biomass of their stream-dwelling larvae often exceed that of salmon. 

But you don't often see adult metamorphosed Dicamptodon unless you get your jollies removing old road culverts, wandering the woods on rainy nights, or dissecting the nests of Pomo tree mice.

Not that encountering Big Sally doesn't happen now and then in other ways. Finding terrestrail Dicamptodon is serendipity for some, and a quest-worthy adventure for others.

In the 1940s a well digger named Dan Coon flushed several of the seldom seen sallies out of springs in the Santa Cruz Mountains.

The discovery fueled the imagination of herpers young and old.

We viewed Dicamptodon as a deeply fossorial Orpheus that climbed out of the underworld only in darkness, and perhaps only on rainy nights.

Its nocturnal peregrinations could only be accounted for by a Swiss made circadian clock and a supernatural ability to sense meteorological changes deep in the earth.  

Latter day Dicamptodon enthusiasts however found that its subterranean retreats included root channels and the burrows of fossorial rodents, usually about 3 feet deep.

This was a disappointing finding for old boy naturalists, but ecologist Gary Fellers and coworkers recently bolstered our somewhat diminished awe.

When Point Reyes National Seashore replaced 4 old rusty culverts with bridges for the restoration of salmon streams, biologists were required to stand vigil and assess habitat for the federally protected California red-legged frog (Rana draytonii).

While bearing witness to back hoe and dozer the researchers discovered assemblages of 23 and 27 metamorphosed Dicamptodon under two of the culverts.

Amazing, huh?

And that's not all.

Recent investigations of tree vole nests by Eric Forsman and James Swingle uncovered an old record of a large Dicamptodon cohabiting with a litter of Pomo tree mice -- 2.4 meters above ground.

Okay, back to the raccoon . . .  it probably discovered big sally on the trail after a recent shower.

If Sally bit, barked, thrashed, and released noxious compounds in self defense, the ploys didn't change the fatal course of events.

Those sensitive coon paws probably gave Sally a rude rubbing and rolling before the jaws clamped down.


[Nota Bene: For the sake of names dropping, I might add that Mr. E.S. Dethlefson, Mr Coon's friend who recognized the significance of the flushed salamanders and published the report, lived down the road from my grandparents house in Ben Lomond, California. Here's a bit about my early days there.]


References

http://www.env.gov.bc.ca/wld/frpa/iwms/documents/Amphibians/a_coastalgiantsalamander.pdf

Dethlefsen, E.S. 1948. A subterranean nest of the Pacific giant salamander, Dicamptodon ensatus (Escholtz). Wasmann Collector, 7(3):81-84. 

Fellers, G.M., L.L. Wood, S. Carlisle, and D. Pratt. 2010. Unusual subterranean aggregations of the Califormia giant salamander, Dicamptodon ensatus.  Herpetological Conservation and Biology, 5(1):149-154.

Forsman, E.D. and J.K. Swingle. 2007. Use of arboreal nests of tree voles (Arborimus spp.) by amphibians. Herpetological Conservation and Biology, 2(2):113-118.


Friday, November 19, 2010

The Bewitching Fog shrew


Getting a half-way decent shrew picture is an occasion for jubilation and a bottle of beer.

And this, kind readers, appears to be a Fog shrew (Sorex sonomae) -- two-toned and in the middle of its fall molt.  From the wilds of Marin County,

Bewitching, wouldn't you say?

Did I hear someone say BS?

Okay, I don't know it's a Fog shrew for certain, because shrews are buggers to identify and it helps if you're nearsighted.

You really need to get their skulls out of their heads, or at least give them a microscopic dental exam.

But among Western North American shrews the Fog shrew is a biggie -- up to 150 mm in total length, and if you know the size of big leaf maple leaves, like the one next to this shrew, then you know this is a big shrew.

The Fog shrew also has a unicolored tail, while most western shrews have bicolored tails with much darker dorsal surfaces.

An identity crisis has dogged this shrew for many years.

Hartley H.T. Jackson, who by the way wrote his first scientific paper at the tender age of 15 when most boys are doing other things,  called it the Pacific shrew (Sorex pacificus).

But not for its peaceful disposition. It's at home in the cool coastal forests from northern Oregon to Marin County in California.

Three and a half decades later a young Jim Findley demoted it from full species to a subspecies of the puny but more widespread Wandering shrew (Sorex vagrans sonomae). It was the macro-shrew at the end of the Rassenkreis.

The late medical doctor-mammalogist Murray Johnson and B.T. Ostenson took issue with that decision, but the demotion stuck for forty-five years.

Then Leslie Carraway, a high-powered lady from Texas with an obsession for shrews concluded that it was not the wandering vagrans.

She elevated its rank to the foggy sonomae, and for the time being her word is final.

Such is taxonomy.

Christian and I set the camera close to the ground at a small spring that debouches from a patch of ferns.

We were lucky.

If you want to camera trap shrews you really have to enter the netherworld of duff and detritus.

You need a tiny camera trap with a short focal length.

You need a lure that smells like slugs, centipedes and worms.

It was just good fortune. The Fog shrew ventured out of the duff.



References

Carraway, Leslie N. 1985. Sorex pacificus. Mammalian Species, No. 231, pp. 1-5.

Verts, B.J. and L.N. Carraway. 1998. Land Mammals of Oregon. University of California Press, Berkeley

Wednesday, November 17, 2010

Cautious coyote

August 21, 7:21 PM, Set 320


"Whenever the pressure of our complex city life thins my blood and numbs my brain, I seek relief in the trail; and when I hear the coyote wailing to the yellow dawn, my cares fall from me - I am happy."

Hamlin Garland

Couldn't agree more.

Monday, November 15, 2010

Four visits -- four views

August 17, 1:27 AM -- Day 6

Back from a few cool days on the Chimineas, the camera trapping wonderland, but I am running a bit low on material.

The previous trip was a hard act to follow, and this time there were no surprises -- only the usual suspects

So we're serving up a few shots of bobcat(s) from a 38-day set made by the team in mid-August.

This is on top of the rock pile where we photographed a bobcat last winter.

The bait is secreted in the crack between the two rocks at the right.

None of the pictures was cropped, so you can see how the cat(s) moved around on the 4 occasions it visited the set.

August 22, 1:33 AM -- Day 6
Yes, the first two pictures of the same cat.

Aug 22, 9:39 PM -- Day 11
And it looks like she visited again 5 days later.

August 27, 10:28 PM --  Day 36

Not sure it was the same cat on the last visit, because it's behind the rock on the left.

It was upstaged by a moth impersonating a bat with landing gear deployed.

Wednesday, November 10, 2010

Barny moves on


It was twenty-five days into Barny's nocturnal escapades when the she-pig came back.

She downed the camera trap with porcine recklessness, but paid it no further heed.

It lay on its back, three round eyes to blazing sun and starry night.

Our good fortune with Barney though wasn't yet over.

Two nights later --  at 9:41 to be exact, she appeared out of the darkness like a red-eyed Valkyrie, and the camera recorded her passing.

It was the only photo of her that night. If she touched down in the swale she kept her distance.




She made 8 more visits during the next 11 days, but we don't know if she played with the seed heads.





On each visit however she peered at the waylaid camera, sometimes looking down through her toes  . . . and sometimes leaning in from the side.



Then she disappeared into the night.




We'll be back at the grassy swale looking for Barny next year. 

Sunday, November 7, 2010

Barny's adventures, continued



It seemed that Barny was a-huntin'.

Like a Peeping Tom she spent a lot of time peering -- peering into the trampled grass.




A wee sleekit beastie' was probably crepitating therein, and Barny, it seemed, was channeling the sound with her facial disk.




That's how I read the photos, but I needed confirmation.

Hans Peeter's Field Guide to Owls of California and the West made no mention of barn owls foraging on the ground . . . had we made a discovery?

I sent Peeters a message and he answered . . .
I myself had never heard of Barn Owls foraging on foot, although it wouldn't totally surprise me. This species, however, is so highly aurally inclined in its hunting that infantry-style foraging would be a surprise. Do you have videos? All owls, having pounced on prey and missed, do a certain amount of walking about and weaving their heads from side to side to obtain auditory clues, and all seem to be far-sighted and therefore back up from the point of impact and try to locate the prey by sight. 
I quickly googled up a minor paper at http://www.fosbirds.org/FFN/PDFs/FFNv26n3p91-93McMillian.pdf which seems to present pretty good evidence of foot hunting by Great Horned Owls, and it mentions other references (though I couldn't locate any discussion of the phenomenon in Johnsgard, which the author mentions. I am also not entirely convinced that his owls actually ate the tern eggs; eggs of ducks and coots not infrequently turn up undamaged in GHO nests, having slipped out of the bodies of prey brought there. Such eggs are not eaten and become part of the nest detritus. 
At any rate, if you can provide more detail or video of the foraging on foot that you have seen, I would very much like to see it. 
Then came another message . . . 

While ruminating about your pedestrian foragers, I remembered that I have seen Burrowing Owls hunt crickets on foot during the day; of course that species is highly visually oriented and more or less cathemeral, so that's no great surprise. The Eurasian Tawny Owl, however, is completely nocturnal but also forages for earthworms on foot sometimes (I've seen Red-shouldered Hawks do so in the daytime, rather surprisingly, since it's such insubstantial prey for such a large raptor).

The codger was highly gruntled with the finding, and began daydreaming about ways of getting the evidence in video.

The problem was time. The days were getting shorter and we hadn't even scheduled the next trip to Chimineas.

Meanwhile, Craig succumbed to curiosity -- he hauled his live traps to Barny's stomping ground, and though he caught deer mice and pocket mice in the neighborhood, harvest mice were the only mice in the swale.

Once again I poured over the photos searching for some hint of the elusive quarry . . . some telling crumb of evidence in the corner of Barny's beak, like the spurred femora of a Jerusalem cricket.

At last I found some frames of suspicious activity -- Oh my God! -- frames of Barny holding something fuzzy in her beak.

I dragged the jpeg into Photoshop and zoomed in.

The victim was no wee mousie -- but the seed head of annual rabbitsfoot grass, Polypogon monspieliensis.  



There was actually a sequence -- Now Barny was gripping a seed head in her talons.

Then she was either eating it or tearing it apart!




Was Barny pouncing on imaginary mice in the form of grass seeds?




And sampling them for texture and digestabilty?







The swale seemed a strange and risky place for Barny to hone her hunting skills, if that is what she was doing. 


A predator could explode out of the grass and catch the owl in the midst of her baffling game.


All good things do come to an end, don't they?