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Native Californian, biologist, wildlife conservation consultant, retired Smithsonian scientist, father of two daughters, grandfather of four. INTJ. Believes nature is infinitely more interesting than shopping malls. Born 100 years too late.

Sunday, January 20, 2013

The fog shrew's identity crisis

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Set 587 was in a thicket of ceanothus and sword fern, on a steep logged hillside, riddled with mountain beaver burrows.

I think you know what I was expecting.

No mountain beaver waddled into the camera's view, but a bear left one picture,





















The picture of its paw didn't tickle my curiosity to surf the web for information on ursid foot anatomy.

There were many photos of a fox sparrow scratching for insects and seeds. No surprises there.



The critter at the top of the page was too small to see on the camera's LCD, but when I uploaded the photos at Terry's house I saw something unusual -- a large cinnamon-colored shrew.

I pulled a copy of Jameson and Peeter's California Mammals  (the first edition) from my friend's bookcase, and gleefully discovered that I had camera-trapped my 6th species of shrew -- Sorex pacificus -- Cowabunga!

I celebrated with my friends that night -- two beers and a Mexican dinner.

At home a couple days later I looked up the shrew in my own copy of Jameson and Peeters, the 2004 edition.

Sorex pacificus was gone.

A taxonomist had put to rest northern California's  cinnamon-colored shrew known as Sorex pacificus and reincarnated it as Sorex sonomae, the fog shrew.

This had taken place sometime between the two editions of the field guide.

My list of camera trapped shrews was back to 5 species.

Sorex sonomae has been caught up in an ongoing cycle of taxonomic death and reincarnation.

I bored you with the fog shrew's taxonomic story once before, but this event stirred me to revisit the story of the fog shrew's identity crisis.

This slow-moving drama actually began in 1858 at Fort Umpqua, Oregon, a trading post of the Hudson Bay Company, where a U.S. Medical Inspector named E.P. Vollum acquired a large reddish shrew.

Recognizing its scientific value, he sent it to the Smithsonian Institution where it was safely stored with other stuffed shrews and their skulls.

Some 30 years later (1877) it caught the interest of the bearded surgeon-naturalist Elliott Coues who described it as a new species, Sorex pacificus.

In 1895 the naturalist-Oregonian, B.J.Bretherton collected another large reddish-colored shrew from Yaquina Bay, less than 50 miles from the type locality of Sorex pacificus. 

The man who was to describe it as a new species, 
Hartley H.T. Jackson was 4-years old at the time. 

That year C. Hart Merriam,  Chief of the USDA's Division of Ornithology and Mammalogy, was wrapping up his synopsis of long-tailed shrews. 


It was based on 1200 specimens from all over the country, and he boiled them down to 41 species and subspecies.  


Ironically, Merriam, the great taxonomic splitter who described 86 forms of North American Grizzly bears 23 years later, took a hard line on taxonomic splitting. 


In this work he declared that "the multiplication of closely related forms has been avoided". 


"
Sorex pacificus", he wrote, "stands alone and does not require comparison with any other species, its great size and peculiar cinnamon-rufous color serving to distinguish it at sight."  

He classified all the big cinnamon-colored shrews of the west coast as
pacificus, including Bretherton's Yaquina shrew and the other 12 specimens collected as far away as Point Reyes, California. 

And so it was for the next two decades.  Then the 27-year-old Jackson decided that Bretherton's specimen deserved recognition as a distinct species.


He named it 
Sorex yaquinae, and embarked on a 10-year meditation on the relationships of the long-tailed shrews.

In his A taxonomic review of the American Long-tailed Shrews in 1928 he concluded that the Yaquina shrew was only a subspecies of Sorex pacificus.

He also described another large species of shrew that had been collected from the bank of the Gualala River in Sonoma County, California, which he named Sorex sonomae. 

Sorex pacificus yaquinae and Sorex sonomae remained apart taxonomically for 30 years, but a great deal of "new material" (additional specimens) had accumulated in the meantime.

There were 3,465 specimens to examine when a University of Kansas Ph. D. student named James Findley decided to make sense of the highly variable wandering shrew (Sorex vagrans) .

He noted that the long-tailed shrews are morphologically uniform, that cranial proportions vary allometrically with body size, and concluded that body size and color are the only differences of taxonomic significance.

He then went on to revamp a large number of named forms as wandering shrews, Sorex vagrans, including yaquinae, pacificus and sonomae. The three big west coast shrews colored like dead conifer needles became subspecies of Sorex vagrans

Findley's intriguing hypothesis was that wandering shrews were the personae dramatis in a Pleistocene epic of changing climate, landform, and habitat.

He viewed the Fog shrew (sonomae) and its look-alike relatives pacificus and yaquinae as oversized wandering shrews living in isolation on the frontier of the species geographic range.

Their differentiation from the parent stock had exceeded the possibilities of hybridization.

For 25 years the Fog shrew remained just an oversized wandering shrew, but the next players in the saga noted that, "Findley's revision was greeted cautiously by some".

The Pacific shrew and the Wandering shrew were alive and well in the pages of Lloyd Ingles' Mammals of the Pacific States published in 1965.

The new players in the saga, Darwen Hennings and Bob Hoffmann (1977) officially exhumed pacificus as a legitimate species, and recognized sonomae and yaquinae as subspecies. 

Thirteen years later (1990), Leslie Carraway examined the specimens once again and elevated Sorex pacificus sonomae to a full species -- Sorex sonomae, and classified Humbolt County's cinnamon colored shrews (formerly pacificus) as the same.  Sorex yaquinae also got a makeover and became Sorex pacificus pacificus.

To sum it up, our big cinnamon-colored fog shrew of Humbolt County started out as Sorex pacificus, was reincarnated as Sorex vagrans pacificus, was once again reincarnated as its former self, Sorex pacificus pacificus, and was finally reincarnated as Sorex sonomae tenelliodus.   

Not that you cared.

But the take home message for the naturalist blogger is this: use current field guides if you want to get the scientific names right.


(Thanks to Neil Woodman for guiding me to critical references, and to Kristen Bullard of Smithsonian Libraries for getting me PDFs of most of them.)


References: 

Leslie N. Carraway. 1990. A morphologic and morphometric analysis of the "
Sorex vagrans species complex" in the Pacific Coast Region. Special Publications, The Museum, Texas Tech University 32:1-76. (NB: was unable to access this reference)

Demboski, J.R. and J.A. Cook. 2001. Phylogeography of the dusky shrew, Sorex monticolus (Insectivora, Soricidae): insight into deep and shallow history in northwestern North America. Molecular Ecology, 10:1227-1240.

Findley, J. S. 1955. Speciation of the wandering shrew. University of Kansas Publications, Museum of Natural History, Vol.9(1):1-68.

Hennings, D. and R.S. Hoffmann. 1977. A review of the taxonomy of the Sorex vagrans complex from western North America. Occasional Papers, Museum of Natural History of the University of Kansas, 68:1-35.   

Jackson, H.H.T. 1928. A taxonomic revision of the American long-tailed shrews (genus Sorex and Microsorex). North American Fauna No 51:1-238.

Merriam, C. H. 1895. Synopsis of the American shrews of the genus Sorex. North American Fauna No. 10:57-98.

http://www.nps.gov/history/history/online_books/science/14/chap2.htm (NB: Interesting account of C. Hart Merriam by the Murie brothers)

Friday, January 18, 2013

A bit of camera trapping history



If there are any camera trappers out there who would like a bit of camera trapping history to hang in their den or cam-hacking workshop, this is your chance.

The buck white-tail shot by George Shiras, 3rd is for sale.

This is the 275 lb. buck shot by Shiras one-mile west of Whitefish Lake Camp, which can be seen on page 206 of his Hunting Wildlife with Camera and Flashlight (volume 1).

The mount will be auctioned by Scott Heikkila, who lives in the UP knows Shiras's old camera trapping haunts.

Says Scott, "I have been to lots of the places that George has and really like his books and photos.  I have had the head for a long time and would like to see it somewhere that it can be appreciated by more people."  
 
If you interested email Scott at Heikks@hotmail.com.

Sunday, January 13, 2013

Revenge of the Zen-walkers

A "Gotcha moment".

Ah yes, I remember this camera trap fondly and chuckle. 

It was set # 450, which means nothing to you and everything to me. 

It was poorly hidden in a clump of ferns on a cut bank in Marin County, a so-called "trail set".

Now trail sets are not particularly imaginative, and they are often easily detected, but this one almost always caught its quarry off guard.  

Local wildlife seemed oblivious until the camera rudely announced its presence with 4 consecutive flashes.

And among the wildlife that used this lovely trail were three sporting ladies.

They were regulars who would pass the camera Indian-file, just like black-tailed deer.

They could only reach the camera trap after a long aerobic climb of several hundred feet.

Then they would mount a small rise on the trail, descend a few steps, and in the silent splendor of giant ferns, mossy trunks, and stately redwoods -- blink blink blink -- three little red-eye flashes would intrude upon their reverie.

The big flash came a split second later, capturing their priceless reactions.
  
It was as if a vulgar little troll jumped out of the fern and said "BOO"! 

After that rude introduction you would think these good-natured ladies wouldn't forget the troll, but on their next hike the little bugger caught them off guard once again.

I can only surmise that the peaceful exhilaration of their outing lulled them in a hiker's trance or perhaps a Zen-like frame of mind.

Even the Codger had a few Zen moments upon reaching the summit of the trail, most likely a consequence of anoxia.


Another  "Gotcha moment".

Time passed, and Charlotte spun her web over the camera, but the little troll still jumped out and flashed when the ladies passed.  

By now I sensed that the ladies were growing a little tired of the troll's merry pranks.




It was a turning point in the game, but I didn't know it.

The ladies were cooking up a scheme to outsmart the troll on their next outing.

A few days later they circumvented the troll's electronic eye with the stealth of commandos and thrust their surprise in its homely face.    




I think they were making a statement.

"You want wildlife?  You want wildlife? Here it is, you sick little troll. Take all the pictures you want,  and leave us alone".

Look carefully, good readers.

The lady in the shadows seemed to be intoning a curse.  




And the other lady got up close and personal.

I think I get the message.

Ladies, wherever you are, I want you to know the troll greatly enjoyed those fleeting interactions.

I know that your initial amusement, if any, was short-lived, but at least you treated the little bugger much better than bears or the rowdies who steal trail cameras.

Rest assured that the last laugh was on the troll and the Codger himself.

Postscript: The Codger hopes to meet the ladies one of these days and hike that trail for old time's sake. He promises to leave the troll home.  (And readers should know that these good ladies gave permission to use their images through an intermediary and mutual friend.)

Wednesday, January 9, 2013

Orofino Mine in January



Excuse the crappy photos.

It was a cold dark day when I turned off the dirt road and followed the trail down into the woods.

Not a day for photography, and not weather that summons young folk to recreate with libations at a local mine.

But a good day for a codger and his dog to explore.

I've walked past this trail at least 100 times, noticed the beer cans, and knew the Orofino mine was near.

And last week I could have sworn someone was baking bread down there. Now I know it was just another smell emanating from under the hood of my truck.

The faux bread smell peeked my interest. Could someone be camping at the mine?







I followed the trail beside a seasonal creek, and then I heard the clean rush of water -- another creek was sluicing down a trench to my left.

Fred led the way, and there it was -- the Orofino Mine.











No sleeping bears in there, not that the gate would keep them out.






Check it out in the East Paradise topo map, and you see that the mine (Y) actually goes under Powerhouse road.

It seems to have a vertical shaft (the square symbol) above the road, but the shaft is hidden in a patch of Himalayan blackberry.





The mine looks relatively safe. None of the collapsing walls I found in the Indian Spring Mine near by.

It will be a while before the road collapses into the subterranean void below.

Wednesday, December 19, 2012

Canned shrew


Winter is a good time to find canned and bottled shrews.

Many walkers around here deem their daily communion with nature incomplete without the comfort of a brewski or two, and tossing the cans or bottles in the brush is apparently de rigeur.

Shrews are attracted to the containers at any time of year, but codgers can find them more easily in winter and redeem them for cash.

Nonetheless, it's been a coon's age since I've found a canned or bottled shrew.

So when I saw that can of Mickey's Malt Liquor tilted upward in the duff I went for it.

It had several ounces left in it, and I could tell there was something soggy in there too.

Sure enough, it was another Trowbridge shrew (Sorex trowbridgeii).

It was the right size and color, and the tail was bicolored, but in winter the wandering shrew (Sorex vagrans) looks quite similar.


The definitive identification had to wait until I could look at its 4 unicuspid teeth.

The photo doesn't do justice to the structure of the teeth, but it gives an idea of what you see under the dissecting scope.


Just keeping the wet shrew on the microscope stage while lifting the upper lip is a frustrating exercise, but that's what it takes to see the 4 diagnostic unicuspid teeth. Their relative size differs between species. The pigmented upper incisor is also slightly grooved.

Trowbridge and wandering shrews are the two common species I've found here.

Empty beer cans and bottles are not encyclopedias, but looking into them is a good way to learn about your local shrews.

Redeem them at your local recycling center, and you can actually get paid to learn about charismatic micro-mammals.

Monday, December 17, 2012

From homely juvenile to young prince



Bushy-tailed wood rats aren't born beauties. 

In youth they look like any other rat, especially with that ratty tail and brownish-gray coat.




A few months later however, their tails gets hairy and their coats acquire buffy highlights.

This animal of the subspecies Neotoma cinerea pulla was camera trapped last summer in a talus slide in the central Sierra Nevada, and I suspect it is a young adult.

In one night we got 54 photos of several woodrats, and there were three age classes.

Unfortunately, a large bulky rat, presumably a male, was the most timid subject, and all images of it were partial pictures.

The subspecies occidentalis seen in the previous post is more silvery and regal in coloration than these woodrats of the Sierra Nevada.


They are all good-lookers though.

Wednesday, December 12, 2012

A dirty filthy but princely rat

A bushy-tailed pack rat (Neotoma cinerea) in a pile of slabs in an abandoned saw mill (Flathead County, Montana).

They may be the best looking rats in North America, but it doesn't matter. In western Montana bushy-tailed wood rats are regarded as dirty filthy rats.

"How could such a princely rodent alienate so many?" I ask.

"Because they stink, they make a mess, and they crap and piss all over the place", Carl answers.

Carl's photos show the ugly truth happening on his front porch.

Bushy-tail caught during intimate moment
 of fecal assessment. (Photo by Carl Hansen)





A poop-obsessed pack rat seems to nuzzle and whisper tenderly to its fecal pellet.











Bushy-tail aids in the delivery of a fecal pellet
(photo by Carl Hansen)
And here you see the rat aiding the passage of a fecal pellet with the tender care of a midwife delivering a babe.

This may be an example of coprophagy -- recycling nutrients in the fermentation products of the caecum, but never mind.

Even David Attenborough's soothing zoological wonderment at such phenomena would not change the minds of the pack rat's detractors.




A pack rat midden in an abandoned cabin.
The beautiful furry rat has other unsavory habits -- like moving into human habitations and decorating with foliage, twigs, and anything else that strikes its fancy.

The middens become their toilets, glued together with urine and feces, and in due course the reeking mass solidifies, crystallizes, and becomes amberat, which acquires a resinous bouquet, and in fact was once mistaken for Native American peanut brittle by a gang of starving 49ers.

The pack rat however has redeeming qualities beyond its good looks and silky Chinchilla coat.

Scientists now know that this dirty filthy rat is an environmental historian.

Countless generations of pack rats have been contributing to some middens for at least the past 25,000 years.

These paleo-middens are monumental edifices hidden in rocky canyons and caves, and they contain a treasure trove on data on environmental change and its consequences on body size as an adaptation to heat dissipation.

The biologists quickly realized that fecal pellets in paleo-middens were not all the same size, and used Carbon 14 dating to assign ages to feces and associated plant parts.

They validated the relationship between pellet size and body size by examining several species of wood rats, and they did other tests to verify their findings.

Guess what?  Pack rats that lived 20,000 years ago in the shadows of the glaciers were impressive hulks.  They are estimated to have weighed as much as 450 grams (roughly a pound).

They grew smaller as temperatures increased after the last glacial, and by the mid-Holocene, about 6000 years ago they were 20% smaller than their ancestors.

It paid to be big, and even today the bushy-tailed wood rat is the largest living species of its clan.

The old pack rat may have a few nasty habits, but it's still a princely looking rodent.   


"Where is it? The viagra doesn't seem to be working".

Reference

Smith, F.A., J.L. Betancourt, and J.H. Brown. 1995. Evolution of body size in the woodrat over the past 25,000 years of climate change. Science, Vol. 270:2012-2014.