About Me

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Native Californian, biologist, wildlife conservation consultant, retired Smithsonian scientist, father of two daughters, grandfather of 4 small primates. INTJ. Believes nature is infinitely more interesting than shopping malls. Born 100 years too late.

Thursday, February 18, 2010

Fred's Bed is Dead

A good friend once told me he'd rather lose a few years of life than abstain from good eating.

That's how Fred felt about Bed.

In a dog's way he loved Bed, but not for sleeping.

Fred's Bed was a wonderful toy, but it was something to be dragged, bitten, and humped with reckless abandon.

Stern admonishment to "Be gentle", got a brief panting pause as he waited for us to go away.

Even if he understood that Bed had a finite life, and that gentle play would make Bed last longer, he wouldn't have cared.

He wanted to enjoy Bed to the fullest.

So Bed was stored behind the closed door of the guest bedroom, and Fred's play dates with it were reserved for special occasions.

Finally our warnings came true. Bed started to lose its stuffing.

This made Bed even more fun to Fred.

We soon tired of re-stuffing Bed and explaining the inevitable.

The time had come.

Last Tuesday Bed was consigned to the trash can.

Fred had loved Bed to death.

And now that Bed is gone, Fred doesn't even miss it.

Tuesday, February 16, 2010

Sausages and Cheese Sandwiches

You can rely on The Outdoor Pressroom to alert you to all kinds of fish and wildlife news, and this morning it was the sausage-baiting camera trapper that got my attention.

This New Yorker's sausages attracted white-tailed deer and a coyote, which leaped for the dangling goodies like the legendary fox of Aesop's fable. 

Reminds me of the baiting advice offered over 8 decades ago by photographer William Nesbit in his encyclopedic book How to Hunt with the Camera.

"Cheese sandwiches are a good all-round bait because they last during hot weather while fresh baits quickly spoil.

"It is my practice to place out bait lines, connecting by their means the various paths through the woods and stream courses.

"These bait lines consist of baits suspended by wires along animal trails. . .

"Animals following any of these paths will probably find a bait and follow the bait line to one of the trap outfits.

Baits and lures are a sure way to stage a wildlife picture, but every state has its own regulations regarding the baiting of wildlife.

A few camera trappers make do without baits, and often get stunning results.  

By the way, Nesbit's book devotes a 17-page section to "Flashlight Trap Photography" or camera trapping, and it sure makes you appreciate modern technology. 

Sunday, February 14, 2010

On camera trap abusers

Most camera trappers would agree: these apes were kinder and gentler than many yokels who encounter a camera trap in the forest.

Check it out here.

And many thanks to Johanna of CougarMagic for sending the link.

Thursday, February 11, 2010

A year in Marin

Time to summarize a year of camera trapping in Marin County.

Our camera trapping beat in the redwoods, coastal scrub, and mixed deciduous woodlands, is home to about 28 species of land mammals and year-round or seasonal home of about 144 species of birds.

The goals were to carry out a simple recce of medium-size or meso-mammals and to provide the Audubon Canyon Ranch with the resulting photographs for their education program.

Cameras were set on trails, and we used a few scent lures only for the first few sets.

So most of the time the cameras monitored normal trail traffic.

1167 (92%) of the photos were of mammals, and the remainder of birds.

8% of the mammals were people (hikers and school kids).

The graph shows that the most commonly clicked subjects were black-tailed deer, brush rabbits, and western gray squirrels.

Of course some of these photos were repeated images of the same animals coming and going, or weaving on and off the trail.

But all the same, these are abundant species that feed the predators in the area.

We photographed 39% of the 28 mammal species known in the area and only 6% of the 144 species of birds recorded in the area.
That's not surprising.

We were not trying to survey birds, but even if that was the goal, camera traps are not the tool of choice.

If the goal had been a comprehensive survey of mammals we would have fallen far short of the mark.

The problem is this: some species, like bats, shrews, moles, and yes, shrew-moles just aren't very detectable by camera traps, unless you make special efforts.

If you take those mini-mammals out of the equation, we photographed 55% of the mammals known on the property.

Obvious omissions were the black-tailed jack rabbit, striped and spotted skunk, and mountain lion.

The absence of mountain lion photos is understandable, though one was seen in late spring and not far from a camera.

Certainly there is no shortage of lion food in the area.

But where are the skunks?

Road killed skunk has always been a common sight in Marin County, and normally they are highly detectable by camera trap.

Did an epidemic -- rabies, canine distemper or some other disease -- lay the skunks low?

Food for thought.

Another thought is that periodically compiling results is a good way to drive home a few messages.

First, sampling all habitats increases the chance of recording more species.

We covered one habitat intensively, but need to spend more time camera trapping coastal scrub and redwoods.

Second, camera traps are best at capturing medium to large mammals, and ground living small mammals like rodents.

We will have to work a bit more to find microhabitats and amke camera trap sets for shrews and shrew moles, and perhaps bats too.

Third, there is no fixed amount of time that will reveal all species in a given area detectable to camera traps.

Populations change. Mammals are subject to epizootic diseases that periodically reduce populations to very low levels, often over areas larger than the sampling areas biologists use for camera traps.

Fourth, the Marin experience proved that the longer you wait the better your chances of photographing something interesting.

It didn't take long to figure out that set 228 was in the core area of a bobcat's home range.

We monitored one short length of trail for 8 months, and were rewarded with photos of bobcat kittens, and a cat carrying a recently caught gopher snake and brush rabbit.

And finally, many thanks to Gwen Heistand and her staff for their interest and help.

Monday, February 8, 2010

Camera Trapping Workshop--July, 2010

Deadman Peak and Deadman Lake, near the Sierra Nevada Field Campus

My camera trapping workshop has been scheduled once again at San Francisco State University's Sierra Nevada Field Campus.

For information about the field campus and its course offerings click the website here.

You can also get registration materials at the website.

Regular readers of this blog have seen how much fun camera trapping can be, so I hope some of you will be interested in enrolling.

If you are interested, read on.



July 18-23, 2010
Sunday, July 18

  • Arrive: noon through late afternoon.
  • Dinner: 6:00 PM. 
  • Evening: Class introductions, workshop goals, and participants voice their special interests. 
  • Power Point presentation: History of camera trapping.
Shadow chipmunk at the field station -- a good teacher 
about the topic of framing photos

Monday, July 19 

  • Breakfast: 7:00AM (make your own bag lunch) 
  • 8:30 AM: Topic: Making camera sets. “Macro sets” near camp (close–ups of golden-mantled ground squirrels, shadow chipmunks, chickarees, and mountain beavers): hollow log, burrow entrance, and natural feeding stations--like seed and cone middens. 
  • Activity (mid morning): Collect cams at Red Fir Ravine (car pool to site, short hike up into ravine) or stay in camp with own cameras. 
  • Lunch: in field or in camp
  • Afternoon: Return to field campus, download photos, compare results from morning sets.
  • Dinner: 6:00 PM 
  • Power Point presentation/discussion: Camera trap sets (trails, waterholes and natural and artificial attractions); special sets: arboreal, hollow log, and subterranean; Predicting behavior and pre-visualizing images. 
  • Other Topics covered: Camera attachment (trees versus posts, telescoping poles, bungies, cables, special attachments, hardware), camouflaging cameras, camera security (people and bears), PIR sensors (strengths and weaknesses), “GPSing” locations of sets. 

 We'll set some cams at Deadman talus slope for pikas

Tuesday, July 20 

  • Breakfast: 7:00AM (make your own bag lunch) 
  • 8:30 AM: Use of baits and lures: legal restrictions, visual, scent and sound lures.
  • Activity: Set cams on talus slope/rock slide (pikas, marmots, weasels) (car pool to site.
  • Lunch: in field 
  • Afternoon: Return to field campus, check cams near camp, download photos, compare results. 
  • Dinner: 6:00 PM 
  • Power Point presentation/discussion: Passive infra-red sensors and other triggers, using white flash of infra-red illumination, using external flash, reducing eye shine, etc.
  • After sunset: Owl calling (car pool to site) 

A spring in Red Fir Ravine, 
where saw whet owls bathe, and mountain beavers forage.

Wednesday, July 21 

  • 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: Animal psychology for camera trappers, species differences in behavior and movement. 
  • After sunset: Flying squirrels: observations and photography. 

Marten photo taken the night before the course in '08; 
the cam had been there a month.

Thursday, July 22 

  • 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 presense-absense (single species versus general surveys), population indices, and special research applications. 
  • General discussion: Topics of class choice; hand out evaluation forms (questionnaires); copy and share photos taken during course. 

Golden -mantled ground squirrel in a hollow log

Friday, July 23

  • Breakfast: 7:00AM (make your own bag lunch) 
  • Activity: (1) collect cams and pack, (2) return evaluations (3) class photo 
  • Farewell and Departure

Sunday, February 7, 2010

New camera trapping blog

I was thrilled the other day to find a new camera trapping blog -- Remote Camera Trap -- South Africa, by Henry de Lange.

The blog is a bonus for camera trap aficionados-- I mean, its not like there's a surplus of blogs on the art and science of camera trapping.

But Remote Camera Trap - SA will be equally interesting for those with broader geographic interests in zoology.

Browse his posts and learn about South African mammals large and small, as well as camera trap surprises, like budgies.

What's more, blogger Henry is a software developer, and offers his software to kindred spirits.

Wildlog is a "wildlife sighting tracker". It's a freebie.

Be sure to download version 1.6.

Thursday, February 4, 2010

Beep beep, there she is again

Yep, Roadrunner used the gulch almost as much as the bobcats.

Thrice she made a showing, slyly looking here and there, long enough to give us 19 photos.

The wily bird was obviously checking the place out for reptiles or unsuspecting dickey birds, especially on the banks above the bed of the gully.

In the southwest these customers are known to snatch and gobble hummingbirds from nectar feeders.

They say the therapists in greater Albuquerque do a brisk business treating garden birders for psycho-trauma.

I once saw Roadrunner making house calls in Corrales, NM.

Lizard season hadn't yet opened, and it seemed everyone in the neighborhood knew the bird's schedule.

Roadrunner called in late afternoon, checked out the bird feeder, and then peered through the sliding glass door.

When the door opened she strutted expectantly into the kitchen.

There she gulped a couple of raw hamburger balls big enough to gag a Rhode Island Red.

Wednesday, February 3, 2010

Who else?

Well possums, your guesses are all reasonable.

Bobcats would certainly cruise for wood rats and bunnies, as proffered by Doug and Desert Nutmeg, but neither showed up at set 312.

No hikers, either, Doug.

And coyotes definitely frequent the haunts of bobcats and vice versa.

In fact, one yodeler, seen above, did make a fleeting appearance just before noon on December 5th.

So Owlman and Randontruth actually picked a species that made a showing.

But Coyote wasn't a heavy user of the gulch.

Beep beep -- tomorrow night I'll post the answer.

Tuesday, February 2, 2010

Bobcat bonanza

From the standpoint of scenery there was nothing special about set 312.

It was just a narrow defile, a very old and slightly winding erosion gully in a steep hill.

Craig found it and I am glad he did.

Thirty-five days later the cam snapped his picture a few moments before he pulled the camera.

Macy is leading the way.

The camera snapped 88 pictures of which 30 were blanks.

The amazing thing is that nearly 60% of the animal photos were bobcats.

We got them coming,

and going.

Check out their left forelegs and you will see that at least these two cats were different kitties.

We counted nine different visits, where a visit is one or more photos clustered in time.

It seems the defile was a passage way for at least two bobcats. 

Now then, what was the next most common user of the defile?

Go ahead -- take a guess.