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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.
Showing posts with label 2011 Camera Trapping Workshop. Show all posts
Showing posts with label 2011 Camera Trapping Workshop. Show all posts

Sunday, October 23, 2011

The Restless Haystack

A mountain beaver or showtl on the job -- is it making hay or pitching its tent? 


In 1995 Mark Johnson published an article on tents that cover the burrows of mountain beavers.
"Supporting sticks were placed over and across the entrances. Then, sticks were placed perpendicular to these over the entrances. Finally, leafy sticks of big leaf maple (Acer macrophyllum), sword fern (Polystichum munitum), or both were placed across the sticks concealing the entrances." 
The tents were clearly the handiwork of the showtls and not the caring gesture of a passing Sasquatch.

Not all burrows had tents, but Johnson thought they may keep burrows dry in a rainy climate.

Though usually agreeable, showtl enthusiasts have at times disagreed about the animal's tolerance of water.

A pioneering student of the showtl, C. A. Hubbard opined that the rodent shuns watery tunnels, "because Aplodontia cares for water only as  a drink."

Lloyd Glenn Ingles on the other hand averred that, "Living as it often does near water, the animal is a fine swimmer."

Yours truly and his student camera trappers have also given photographic proof that showtls and their neighbors have no qualms about scooting through watery tunnels.

I have the feeling that the showtl's tent may be a drying rack for plant cuttings, that is, nothing more than a haystack, and haystacks have also been reported numerous times in the scientific literature.

The big question is about the criss-cross arrangement of the sticks.

Are they an act of God or an act of mountain beavers?

I've assumed they were an act of God, that they just happened to be there as they had fallen from the trees.

We have actually removed a few sticks from some burrows for better pictures, and if the rodent replaced them with others, I for one didn't notice.

But I am greatly intrigued by Johnson's suggestion, though apparently based on circumstantial evidence rather than direct observation.

A rodent that builds a tent or a drying rack by dragging sticks over its burrow is a remarkable rodent.

It's a tool user.

So confirming Johnson's tent-building observation is on the list for next year's showtl work.

If you haven't seen a showtl's haystack, here's a sequence of 30 photos taken during a week near Yuba Pass, California.

Try to stay awake. It's less than a minute and the action gets exciting at the end.





References

Hubbard, C.A. 1922. Some data on the rodent Aplodontia. The Murrelet 3(1):14-18.

Ingles, L.G. 1965. Mammals of the Pacific States. Stanford University Press, Stanford, California.

Johnson, M.K. 1975. Tent building in mountain beavers (Aplodontia rufa). Journal of Mammalogy, 56(3):715-715.

Wednesday, October 5, 2011

Trowbridge shrew



I mistook this for a mouse, but on the computer screen at home it was clear that the ears were too small.

There are two species of shrews in the northern Sierra Nevada that sport brown summer coats and bi-colored tails.

The Wandering or Vagrant shrew (Sorex vagrans) prefers open meadows, while Trowbridge's shrew (Sorex trowbridgii) is found in conifer and mixed deciduous forests.

This hollow tree is in an extensive stand of red fir; so I am assuming we are looking at Trowbridge's shrew.




Shrews don't stay put, and they tend to be found in microhabitats overlooked by most camera trappers.

It's a special occasion when I get a photo of one.

Sunday, October 2, 2011

The bear comes back



That hollow red fir in Sierra County was an enchanting place, and I wasn't ready to pull the camera after just one month.

A natural shelter like that is such an attraction to wildlife that you never know what's going to stick its head in the door.




The yearling bear visited on four more occasions, giving us a better selection of portraits, but on the second visit it knocked the camera ajar.




We might have missed quite a show if it had remained pointing at the entrance, but by a stroke of good luck it was still upright and aimed at a pile of carpenter ant frass.

Next time you'll see an incidental visitor, after that an unabashed show of sensuality.

Wednesday, August 31, 2011

Showtl's Underworld, Part 2


Six hours after we left, Showtl made its first appearance.  

What a difference a month can make during the growing season.

We bumbled about looking for the underground cams.

Alders in full leaf and knee-high grass covered the landmarks we expected, and we fell back on the GPS and Audrey's cognitive map to find the underground cameras.

But showtl didn't let us down.

Our rodent made almost daily appearances, which means the site was probably located near its nest.




Only 21% of 281 exposures however contained animals. The rest were blank images.





Normally we'd blame this on moving vegetation and phantom puffs of hot air which the infra-red sensor can't distinguish from animals, but this doesn't explain false exposures in the showtl's cool burrow.






It is more likely the rodent was zipping back and forth, and the camera was often too slow to get pictures of it.  

Despite false exposures, we still got 57 images of our quarry, and what you see here are the best. 

What you don't see are the two predators lurking in the tunnel.  

They're coming soon. 

Monday, August 29, 2011

The Showtl's Underworld



My obsession with showtls took a new turn this summer.

We attempted our first subterranean camera trap sets.

Two hours later two cameras were positioned to capture photos of the beastie in its underworld.

The showtl's tunnel was squarely in the middle of an alder thicket, and Montana Carl announced his intention to stay clear of alder, which he claimed had taken liberties with his person ever since the first day of the workshop.

In point of fact, springy alder limbs had been goosing all of us.

Making the sets therefore fell on the shoulders of the more agile young folk, while the two codgers sat on the sidelines to kibbitz.




The first task was to find the best location.

Several cave-ins had left gaping holes, much bigger than showtl burrows, that murmured of water and mosquitos within.

"Who's gonna stick their arm down there and take some pictures of the tunnel?"

Seabass volunteered.




The pictures showed us that the tunnel was anything but straight, and passed through a morass of buried timber and roots.




In some places it was an open trench. 




Next, we had to decide which cave-in gave the best subterranean perspective.

Snow water had created a small cavern immediately inside one of them.

It was an ideal situation for a camera trap: we could stake the camera and yield right-of-way to passing showtls.

Seabass drove a 1" pipe into the bed of the subway, and lowered the cam on its mount to just above the water.




The afternoon dragged on as we fine-tuned the camera's position, but we were all fluffed up with our cleverness, and for good measure we hurriedly staked a second camera down another chute.

Then we headed back to camp for a well-deserved happy hour.

Thursday, August 25, 2011

Camtrappers' rendezvous

Seabass enters the lair of the bear

Yes, sometimes you find a bear in the den, and sometimes you just look like you found a bear in the den.

Readers of Camera Trap Codger may have forgotten that only a month ago the stalwart class of 2011 deployed their final camera trap sets with remarkable derring-do.

I'm reminding you again, because this week we assembled on the north branch of the Yuba River to gather those cams.

It was a mellow late summer day, not unlike a rendezvous of mountain men.

The difference was that the trappers included three women, there were no Indians, no one bartered beaver pelts for trade goods, and there was no booze.

This latter point was an issue of some regret, as one of the ladies rather convincingly made the point that an alcoholic libation would have been an appropriate conclusion to such a productive day.

Next time.

Despite the aid of GPS we bumbled about finding our sets, but we had a good day and made a good haul.

It's going to take the Codger some time to tabulate the data and ponder the material, and I pen this post to alert you that the next few communications will highlight the results.

And you will not find all of the results here either;  some "free trappers" were working the area too.

If you do not subscribe to Nature of a Man and Camera Trapping Campus, shame on you, but be sure to check those blogs by the Codger's trainees.

Their transcendental essays and evocative photos will be well worth your time.

So stay tuned and have patience as we crank out the results.

Thursday, June 23, 2011

The call of the high country

Christian finishes his log set.

The high country was calling, "get off your butt and set some cams -- the camera trapping workshop is only a month away".

So the codger spent a day in Sierra County in good company -- "graduates" from last year's Camera Trapping Workshop plus friends.

The northern Sierra still has plenty of snow.

Forest Service roads weren't always passable; snow drifts were thick on the north slopes.

And the Yuba River wasn't fordable by the usual routes and means: rock-hopping, wading, or crossing fallen logs.


The high country in Eldorado County, where I found more mountain beaver habitat this weekend.


That didn't stop us; we put out a record number of cameras in several habitats.

We GPS'd each set because in only 4-weeks the growth spurt of grass and Delphiniums will drastically change the appearance of each location.

I was pleased to observe that the guys learned their camera trapping lessons well and gained a great deal of experience on their own this past year.

Now they're pushing the envelope for camera trapping creativity.

What you can't see in the picture above is that Christian's camera trap is only 12 feet or so above the whitewater!

Okay, I'm joshing.

But in a few weeks when the drifts melt there'll be a lot more water flowing under his lofty perch.

And for other high jinks and discoveries from last weekend check Camera Trapping Campus.

Sunday, March 20, 2011

Camera Trapping Workshop -- July 17-22, 2011

Looking toward Sierra Valley and its wetlands. 

Once again good readers, I will be giving the camera trapping workshop at San Francisco State University's Sierra Nevada Field Campus.

This will be the third course, and I've been making incremental improvements in the presentations and activities as a result of growing familiarity with the location and input from participants.

We have definitely nailed down the whereabouts of several additional species of small mammals not far from the campus, but we'll also range into surrounding areas to cast the camera trap net more widely.

As in the past, I'll set several cameras in the field a month before the workshop, and we'll gather them and view the photos during the week.

Be sure to bring your laptop for downloading and viewing photos, and a GPS, if you have one. I'll provide you with camera trap data notebooks.


Basically, we'll cam trap daily and move through the subject matter using powerpoint presentations and discussions.  

Click the Sierra Nevada Field Campus website for information about the field campus and its course offerings, including Photographing Wildlife with Camera Traps.

Registration materials are available at the website.

I know that regular readers of CTC are well aware of the recreational and educational rewards of camera trapping, not to mention the adventure and sheer fun of it all, so read on if you want to know what's planned. 


Fording the Yuba on the way to Deadman Lake


CAMERA TRAPPING WORKSHOP SCHEDULE 

SIERRA NEVADA FIELD CAMPUS, SIERRA COUNTY, CA 

July 17-22, 2011 
Sunday, July 17
  • Arrive: noon through late afternoon.
  • Dinner: 6:00 PM.
  • Evening: Class introductions, workshop goals and work plan, participants voice special interests.
  • Power Point presentation: Camera Trap Discoveries

Monday, July 18

  • Breakfast: 7:00AM (make your own bag lunch)
  • 8:30 AM: Power Point presentation: Camera trap structure and function and Camera Trap "Set Theory"
  • Other Topics covered: Camera attachments and mounts (low to high tech solutions).
  • Activity (mid-morning): Hands-on instruction in pre-visualizing images and anticipating animal behavior. Subjects = golden-mantled ground squirrels, shadow chipmunks, chickarees, mountain beavers, pikas, bushy-tailed wood rats): Sets = hollow logs, burrow entrances, and natural feeding stations--e.g., seed and cone middens
  • Lunch: in field or in camp
  • Afternoon: Collect pre-set cams in the field (car pool to site, and a short hike in) or stay in camp with your own cameras. Return to field campus, download photos, compare results from morning sets.
  • Dinner: 6:00 PM
  • Power Point presentation/discussion: Use of Attractants (windfalls, water, scent/visual/sound lures and baits; legal restrictions).

Tuesday, July 19

  • Breakfast: 7:00AM (make your own bag lunch)
  • 8:30 AM, Powerpoint Presentation: Animal Psych for Camera Trappers (species differences in behavior and sensory perception).
  • Activity: Set cams in field (car pool to site in Sierra Valley).
  • Lunch: in field
  • Afternoon: Return to field campus, check cams near camp, download photos, compare results.
  • Dinner: 6:00 PM
  • Power Point presentation/discussion: Old timey Camera Trap Luminaries
  • Additional activity: Home-made portable endoscope (burrow and cavity video cam)

Wednesday, July 20

  • Breakfast: 7:00AM (make your own bag lunch)
  • 8:30 AM: Topic: camera trapping databases (inventory of sets, spreadsheet of camera trapping results); image database software; digital darkroom software, GPS mapping software.
  • Activity (mid morning): Hike to Deadman Lake and scree (optional, but a chance to see pikas).
  • Lunch: in field (or in camp).
  • Afternoon: Return to field campus, download photos, compare results from morning camp sets.
  • Dinner: 6:00 PM
  • Power Point presentation/discussion: How to be in the right place at the right time.  
  • After sunset: Flying squirrels: observations and photography (tentative, it depends on a good neighbor).

Thursday, July 21

  • Breakfast: 7:00AM (make your own bag lunch)
  • 8:30 AM: Topic: Making your own: General guidelines and links for hacking cameras, i.e., “homebrew” trail cameras.
  • Activity (mid morning): Collect cams from outlying sites (talus slope, ravine springs, mountain beaver burrows).
  • Lunch: in field
  • Afternoon: Return to field campus, download photos, compare results.
  • Dinner: 6:00 PM
  • Power Point presentation/discussion: Wildlife Surveys using Camera Traps (scientific applications)
  • General discussion: Topics of class choice; hand out evaluation forms (questionnaires); copy and share photos taken during course.

Friday, July 22

  • Breakfast: 7:00AM (make your own bag lunch)
  • Activity: (1) collect cams and pack, (2) return evaluations (3) class photo
  • Farewell and Departure
Viewing photos during last year's workshop