My first home brew trail cam

My first home-brewed camera trap was inspired by reading the trail camera forum in Jesse's Hunting and Outdoors Website.

It was bulky, and even when camouflaged in the woods it still stood out like a sore thumb.

The solenoid was touchy, and fine tuning it could waste half a roll of film.

But it was cheap to make.

I already had the camera, a point and shoot Yashica E-Zoom 70, and neighbor Richard generously donated a photoelectric sensor -- a Maxi-Beam Power Block which required a 6 volt battery.

It worked beautifully.

I pulled the requisite 6 volt battery from a spot light. No added expense there, as long as I was willing to switch the battery back and forth.

The only thing I had to buy was the housing -- an army surplus ammunition case.

The resulting contraption was my own creation,  and I was pretty happy with it.

Then I web-surfed my way to a new discovery -- that one can also hack digital point and shoot cameras.

Digital cams were a lot more expensive than film cams, but have many advantages.

The scariest thing was taking a brand new camera apart, drilling holes in the case, and soldering wires to tiny internal contacts.

Now I am a hopelessly hooked hacker and have lost count of my hack-jobs -- at least 50.

Today I dusted off my first home brew and studied the photoelectric sensor.

It has much to commend it as an alternative to the passive infrared (PIR) and active infra-red (AIR) sensors most remote cameras rely upon to trigger pictures.

If I can adapt it to another camera, you'll hear about it here.

Gearing up

A mix of old and new camera traps ready for the field.

Large cases contain 2D-cells as backup power; 

small cases contain 4 AA cells as backup power.

I've been gearing up to deploy additional cams at the Chimineas Ranch and Marin County.

Seven camera traps were out of order, and parts for 5 additional units had been accumulating dust and dog hair for several months.

When I started home-brewing my own camera traps I often encountered problems, and I always thought it was due to some technical failure beyond my limited knowledge of electronics. 

The problem was almost always due to dying or dead batteries in the camera or controller. 

So I got in the habit of using the multimeter, and when something goes wrong the first thing I check are the batteries. 

Weak batteries however were not the problem in these cameras.

The easiest fix only required tweaking.

It was a case of lens impotence.

The lens would struggle to extend while grinding noisily for several seconds, and then it would suddenly appear.

By then of course the animal that triggered the camera was long gone.   

All it needed was tough love. 

Believe it or not, you can fix a jammed lens motor by slamming the camera in your hand while the lens gear is grinding. 

More often however, finding what doesn't work requires fairly simple trouble shooting.

Test the camera with a functional controller,  and vice versa until you know what component has failed.  

Then test the wired circuits for continuity.

Very often there is a short, a solder contact has broken, or a wire has been pinched. 

I repaired 4 of the units by replacing controllers or rewiring the cameras, built 5 new units with new Sony s600s and YetiCam controllers, and laid one camera to rest -- a source of spare parts.  

Fixing a camera makes you feel pretty good.

Sometimes you even hear trumpets blaring that familiar theme from Rocky.  

Camera Trap Pioneers: Charles McDougal

[Chuck McDougal during a tiger drive in the 1980s. 

Photo by Chris Wemmer.]

Charles "Chuck" McDougal began photographing tigers with camera traps in the late 1970s. Not since F.W. Champion's camera trapping achievements 40 years earlier had anyone pursued this kind of photography with such devotion.

McDougal was trained as a cultural anthropologist at the University of Colorado and developed a keen interest in tigers and Nepalese natural history during Ph. D. research on the Rai people of eastern Nepal.

With fluency in Nepali and Rai, he was well prepared for work in the terai after graduate school.

That led to several years of hunting problem tigers in the late 1960s. With the passage of the Convention on International Trade of Endangered Species (CITES) in 1972 the era of sport hunting tigers came to an end.

McDougal devoted himself to scientific studies of tigers when he became the Director of Research at Tiger Tops in the 1970s. At the time, Tiger Tops had the distinction of being the only lodge in a national park where tourists could bank on seeing tigers in the course of a few days.

In my own experience at the time, tiger viewing at Tiger Tops usually interrupted happy hour or dinner.

When the bell rang, tipsy tourists gleefully scuttled into waiting Land Rovers. A tiger or leopard had just killed or returned to the bait -- a buffalo calf.

Ten minutes later they were deposited on a sandy trail in the jungle, where the guide requested you to remove your shoes and remain silent. (I believe the banishment of clodhoppers was a brilliant marketing ploy.)

Then they padded up a sandy jungle path, and five minutes later were viewing the tiger feeding in the light of a torch 100 feet away.

[Photo by Chuck McDougal]

Chuck had been studying tigers in the vicinity of the Lodge when the Smithsonian Nepal Tiger Ecology Project commenced in 1973, and in due course he became a key collaborator with the young American and Nepali scientists who studied tigers and their prey in the park.

McDougal's initial investigations were based on jungle lore -- tracking animals by their pugmarks as popularized by the legendary colonial naturalist Jim Corbett.

Most footprints of young animals are not sufficiently distinct for irrefutable identification of individual tigers. His studies required the ability to individually identify the members of the tiger population. Camera traps were the logical solution.

Tigers left their pugmarks on trails, jeep tracks, and riverbanks throughout the park. Getting pictures was only a matter of being in the right place at the right time. Sooner or later a tiger would amble down the path again.

Chuck's earliest camera trap was a Nikon F2. The model had an accessory electronic shutter release, and this he wired to a switch in a home-made pressure plate. It was built from two wooden planks from the local sal tree (Shorea robusta), and compression springs held the electrical contact apart.

He buried the pressure pad in a shallow depression on a game trail. When an animal stepped on the wooden pad the battery-powered circuit was closed, triggering the camera and its flash.

Here's the story in Chuck's words.

"In early 1972, I started working at Tiger Tops. In 1977, inspired by Champion's tiger photos from the 1920s Mike Price, a Anglia Survial cameraman and still phographer started using a Nikon F2 linked up to a homemade pressure pad. I continued this after he left a few months later and photographed about 20 different tigers in the course of a few years.

"I started using Trailmasters in 1995. The first one I had I put out on the ridge behind Tiger Tops, and I left it there for 3 days. When I went to collect it I found that the tripod had been knocked over and the camera was missing. A young but large male tiger had attacked and carried the camera in his jaws about 80 meters down the path before dropping it. The slide had been knocked off and the camera had canine dents in it. But the photo of the tiger, giving the camera a dirty look before attacking it, came out fine. I sent it to Bill Goodson who put it on his website and gave me a new camera. I still have 2 guys on my payroll camera trapping with the Trailmasters."

Chuck steadfastly improved the system to capture truly outstanding images. He eliminated, for example, the flat appearance rendered by head-on lighting of the electronic flash by placing a slave-activated flash at a 45-degree angle to the trail.

I recall my befuddlement in 1981 when he completed the preparation of a camera set on a trail near the Lodge. He dressed the camera in two quilted mufflers, which made it look like a black effigy on a tripod. The mufflers were beautifully made by the local tailor and stuffed with the unseeded fiber of the local simal or silk cotton tree. (And like all locally made pillows, the muffler was highly attractive to rats hungry for oily seeds.)

Why make the camera look like a black scarecrow?

Well, it solved a vexing problem. In the 'pre-muffler period' Chuck noticed that tigers were often photographed in unflattering moments. They were either frozen in motion veering away from the camera, or they had that unmistakable look of the 'possum-in-the-headlights'.

These responses were testimony to the tiger's lightning reflexes. The big cats actually reacted within microseconds to the sound of the camera's shutter.

As for the pillow-headed scarecrow on the side of the trail, the big cats didn’t seem to notice.

Chuck and his team of two Nepalese camera trappers tallied 8,683 trap-nights of effort and identified 119 individual tigers. They captured a total of 1,309 tiger photos. Most photos were of resident males and females, but each year new tigers appeared, some for a fleeting period and never to seen again, others to challenge and defeat incumbent territory holders.

Over the years he also accumulated an impressive inventory of other wildlife, including yellow-throated martens, several species of civets, and striped hyenas. The rarest find perhaps was a ratel or honey badger. Nowadays it’s an extremely rare species in the subcontinent.

Dave Smith and Chuck McDougal will soon have their book published on the ecology of Nepal's tigers, and I am sure some of Chuck's photos will adorn the pages.

On aquariums and PIR sensors

Will a PIR sensor respond to infrared energy underwater?

I attempted to answer this question today by holding a camera trap against an aquarium, and submerging my arm into the water.

The water was room temperature, considerably less than a codger's body temperature.

The sensor light did NOT respond to my submerged moving arm.

This tells me that a submersible camera trap will have to rely on a trigger based on something other than infrared detection.

The only aquatic mammals we have out here are beavers, muskrats, the water vole, two species of water shrews, otter and mink. There are a pile of diving ducks, waders, and the water ouzel.

I am assuming that even with well insulated coats and plumages, all of these warm-blooded creatures would still give off infrared energy.

If only there were a controller board that allowed alternative trigger mechanisms -- like photoelectric beams.

It looks like I won't be making a cheap submersible camera trap very soon.

But I'm not ready to give up the idea.

Toward a philosophy of camera trapping

Correspondent Alistair Fraser, who can boast some fine wildlife images taken with remote cameras, recently questioned the appropriateness of the term camera trap. Thanks, Alistair, for rattling my cage.

I like the term camera trap for purely sentimental reasons. It was the term that was used before "trail cams" and "scouting cams" became a commercial enterprise, and it goes back a hundred years or slightly more. When my interest emerged in this use of cameras in the 1960s, one had to make his or her own, and the contraption was just called a camera trap.

For me the use of remotely triggered cameras is a vicarious reenactment of a frontier livelihood. It requires traipsing about in the woods, observational skills, a knowledge of natural history, and survival skills. You capture images instead of animals.

Making a "set" with a camera (that's trapper jargon) is like making a set with a trap. You place either device in such a way as to maximize your success. A trapper only wants the creature to step on the treadle, and the deed is done. A novice camera trapper may be thrilled with any image of an animal, but that soon wears off and expectations start to change. Then the camera trapper tries to induce the subject to pose well or show some of its natural behavior. This requires experimentation, practice, prediction, and previsualization, as well as a understanding of how the animal might respond to the circumstances contrived. Reading about a species' ecology and behavior can help a lot.

Trappers target specific species. I am not interested in photographing every bird and mammal in the woods, or only those species that happen to use the trail. Usually I am after specific quarry. Recently I've been thinking about aquatic voles and shrews. Now there's a challenge.

Now don't get me wrong. I don't mind the newer terms scouting camera or trail camera. They are all the same thing, remote automatically triggered cameras. For me the terms scouting and trail cameras also conjure romantic images. Trappers like Jim Bridger were also frontier scouts. Game trails are safer and more fun to use than roads and highways.

But to me a trail camera is just a camera on a trail. A scouting camera on the other hand implies the exploratory use of a remote camera. A camera trap implies a bag of tricks, including the use of smelly substances and roadkill. These distinctions are more about my own philosophy of using remote cameras than semantics.

In my view, those who want superb wildlife images should sit in a blind and control the shutter themselves. Camera trappers will never (or hardly ever) be able to compete with those guys for imagery. (Maybe that's why I just bought a 10MP digital cam with two long lenses.)

Camera trapping is about a lot more than wildlife photography. It offers a certain abstract element that is missing from sitting in a blind with a 500 mm lens.

There's a curiously intimate spatial relationship in camera trapping, because trapper and animal tread the same ground and the camera set is the nexus of interaction.

Part of it is the inherent handicap of leaving so much to chance. You choose a place to leave a camera in the woods, try to create favorable circumstances, and wait for species x to appear.

There's the everpresent danger of losing your equipment to man or bear.

There's the temptation to take a chance, to leave your camera floating on a small raft in a lake, or hidden in a culvert.

There's an element of serendipity when your camera photographs the unexpected, like a clapper rail, shrew, or red salamander.

There are the disappointments and rewards of experimentation.

And there's the thrill of clicking through the images in the field and finding that your set actually did what you had predicted. Huzzzaaaahhhh!

Then you march home and a familiar voice asks that nagging question, "Okay, smartass, you did it once, but can you do it again".

So camera trapping is a harmless way to explore nature, practice woodcraft, reenact a frontier experience, and learn about wildlife. Oh yes, it's also a way to take pictures of wildlife.

I would say it's also a way to enjoy my second childhood, but the family informs me that my first childhood never ended.

Camera Trap Protection

"Be advised, Captain Kirk that nowhere in the galaxy are your camera traps safe from tampering." Spock

A new publication on camera trap protection is always of interest because camera traps are never safe from wildlife and people. This paper in the Journal of Wildlife Management touts the use of a plate steel security box.

The authors, who study wildlife traffic in flood underpasses along a busy stretch of state route 58 in the Mohave desert, had the wisdom to contract a local welder to "armor" their 7 Cuddeback Digital Scouting cameras. The welder was not only paid for his services, but was made a coauther, which is nice to see.

The security box was made of 2 mm steel plates with arc welded joints. A sliding front door with windows for the lens, flash and sensor apertures gives access to the camera, and can be padlocked. I am certain that our state highway department, Caltrans would not approve the use of anchor bolts to fasten the cameras to the culvert walls. So epoxy was used to glue rotating camera mounts on the underpass walls. The cost of materials and labor was $90.

Each camera was deployed with a brief note in Spanish and English explaining the purpose and the ownership of the camera.

The cameras took 107 photographs over a period of 170 days, which by my calculations is 0.14 photos per day or 1 photo every 7 days. The culverts were not a hot area for animal traffic. The wildlife "catch" was black-tailed jackrabbits, desert cottontails, desert woodrats, domestic dogs and a domestic cat. The cameras also photographed 4 people in the culverts, and no traps were damaged, moved or apparently touched over the 6 month period.

With the obvious exception of people, none of these species is a threat to cameras, but I suspect this security box would be an excellent deterrent to bears. A black bear could probably break the wall mount, but it would have to use bolt cutters to cut the padlock.

Most people are not interested in exploring highway culverts, but this changes when nature is calling. A culvert is about the only place in the desert that affords potty privacy. Hitchhikers and hobos also appreciate culverts for shade. The researchers found ample evidence of these human activities. In this situation, the written notice probably had the desired effect.

The online hunting and camera trapping forums, such a Pixcontroller and Real Deal Hunting Chat are good places to learn about camera trap theft, reactions to it, and the ingenuity used to counteract it.

It's my impression that poachers and trespassers pose the greatest threat, because they realize the camera has all the evidence needed for conviction. A chainsaw, however, can even defeat the Python lock. (Just cut the tree down.)

It would be interesting to conduct an experiment to find the most effective deterrent to camera trap thieves. But who's going to do it? It's a lot more fun getting pictures of wildlife.


Reference

Fiehler, C.M., B.L. Cypher, S. Bremner-Harrison, and D. Pounds. 2007. A theft-resistent adjustable security box for digital cameras. Journal of Wildlife management, 71(6):2077-2080