Adventures in camera trapping and zoology, with frequent flashbacks and blarney of questionable relevance.
About Me
- Camera Trap Codger
- 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.
Monday, March 30, 2009
Table Mountain Pilgrimage
There was a great pilgrimage to Table Mountain this past weekend.
It was the peak weekend for wild flowers.
It's a mixed bag of visitors at this time of year.
Yesterday, a cool wind was gusting at 30 mph, and kite fliers were there in full force.
Most were there for the flowers, and some for birds. A minority were content to eat and drink beer near their cars.
And of course there were those seeking other kinds of dalliance.
We were there to smell the flowers, which is something I was accused of never doing in the midst of my career.
Table Mountain is a premier wildflower area, and an intriguing landscape.
Nowadays it's a plateau, but 30-40 million years ago it was a lava cap with a river running through it.
So my advice to you, good readers, is to get off your butts and drink deeply of spring.
It's always full of promise and the very best time of year.
Sunday, March 29, 2009
Indian Spring Mine--an excursion
You can't miss it when you are this close.
The old mine is pretty well overgrown these days, but cans, broken china, cans and old bottles date it back to its heyday from 1860 to the 90s, with aftershocks of activity until the 1930s.
There was sporadic digging after WWII, and at some point in time someone installed a gate limiting access. Some law abiding citizens tore it down and now it lies near the entrance.
Indian Spring Mine is a drift mine, and when DC and his son Brent and I visited last Friday, crystal clear cold water debouched from the tunnel.
Directly beneath the channel of Indian Spring itself the tunnel taps into bedrock at a slight incline.
Tree roots hang in the entrance, and there are a couple of recently collapsed walls.
We weren't prepared to wade into its depths, and saw no signs of bats.
After exploring the mine itself, we followed Indian Spring to a lava cap where water trickled into the channel.
This rather puny flow disappears in the ground nearby, but apparently joins the deeper flow that emerges from the mine.
This is a year round source of water, but there is enough human traffic to make it a security risk for camera trapping. A pity.
[Thanks to D.C.-- a fellow GPSer, for suggesting the outing, and for the use of the last photo.]
Friday, March 27, 2009
Camera trap ikebana
[the ikebana cam, aimed at a coyote latrine
on a mowed path in the coastal scrub]
I'm paranoid about losing cameras to outlaws but lazy about camouflaging them with vegetation.
My rationalization is that few outlaws are willing to traipse through "no man's land" where I put the cams.
I am also certain that Fred and I leave a gamey scent trail in our wake, and no amount of self-flagellation with switches of bay or stepping in cow flops can mask it.
It's said that 2 weeks can pass and a dog can still detect a weak human fingerprint left on a glass slide.
But if you want a full frame picture of a coyote it's still good practice to camouflage your camera trap.
A combination of camouflaged camera, downwind movement of air, and a coyote's mental distraction can conspire to make a good candid shot, or perhaps one at the moment of detection.
So I decorated my latest coyote set like an ikebana master.
The trail was littered with coyote scat, but one latrine was close to a thicket of coyote brush (Baccharis pilularis) and blackberry.
I snipped sprigs of coyote bush and pulled dead grass as the redhead critiqued their placement.
When I finished, the cam wasn't completely hidden, but most of the outline was broken.
The finishing touch was to baste a few turds with coyote lure.
If a yodel dog sniffs them for just a few seconds, I might get a candid portrait.
Labels:
animal scat,
camera trap sets,
coyote,
scent masking
Thursday, March 26, 2009
A scatological note
Wednesday, March 25, 2009
Land of the Free
Tuesday, March 24, 2009
Miniature ice columns
The temperature dropped below freezing yesterday morning, and there were those columnar ice crystals again.
I surfed the web last year to learn more about them, but failed to find anything.
Technically, this kind of ice may not be frost since it is formed from water in the surface soil.
The reddish brown tint of the ice is due to soil particles that were lifted on top of the columns as they formed.
Does anyone know what this kind of ice formation is called?
(Does anyone, besides me, care?)
Monday, March 23, 2009
He may be a genius
Friday, March 20, 2009
Camera shy coyotes
[Jan. 27, 2009; 9:31 PM)
This was the best we did in the coyote department on set 206 in Marin County. (And the picture is cropped.)
The camera was not hidden or camouflaged. We gathered old turds and made an artificial yote latrine not far from the camera.
And we doctored those turds with a commercial coyote scent.
I think the yodel dogs move back and forth on the trail regularly, but most of the pictures looked like this.
Yes, that's a coyote down the trail. Here's another one cropped a bit.
It was a productive set with an 80 - 85% success rate (# animal frames/total # frames), and 3 to 6.6 pictures per day, which isn't bad for a trail.
[Jan 27, 2009; 8:50 AM]
Yes, that's a coyote down the trail. Here's another one cropped a bit.
[ Feb 4, 2009; 9:08 AM]
It was a productive set with an 80 - 85% success rate (# animal frames/total # frames), and 3 to 6.6 pictures per day, which isn't bad for a trail.
Deer traffic was high (305 photos)-- this old fire cut led to a deer trail in the adjacent woods.
We got 18 bobcat photos, 8 pictures of people, and 6 of coyotes.
Plus, a couple of scrub jays, a brush rabbit, and a raccoon.
I'm sure a mountain lion would have eventually shown up, but I wanted to try again in another place, mainly for those elusive coyotes.
I'm sure a mountain lion would have eventually shown up, but I wanted to try again in another place, mainly for those elusive coyotes.
So I pulled the cam and made a new set in the coastal scrub, but this one is camouflaged.
Wednesday, March 18, 2009
End of Year bear
Rich Tenaza just sent me this and several other pictures of a young adult blond-colored bear at the Cleary Reserve.
The cams had not been checked for several months, but were dry and intact, despite heavy rains. (Our luck keeping cams dry hasn't been as good in nearby Marin County.)
The cams had not been checked for several months, but were dry and intact, despite heavy rains. (Our luck keeping cams dry hasn't been as good in nearby Marin County.)
In Rich's words, "The bear was at the waterhole/spring on 28 December from 10:38 to sometime after 10:47 pm. The cam got 42 pictures it in that time. At 10:47 he moved the cam, so that was the end of the picture taking.
"The bear then went to the cougar turd set from 10:54-55 and had his picture taken four times there. He was also there that morning at 5:29 a.m.
"The next day, 29 Dec, he had his picture taken at another cam, where a log blocks the trail, at 5:59 a.m. and again from 10:24-1033 p.m."
This was a winter stroll.
Bears are known to do that, even though they sleep most of the winter.
Bears are known to do that, even though they sleep most of the winter.
Sunday, March 15, 2009
Black-tail's tarsal organ
The tarsal organ is that dark patch of hair on the inside of this buck's hindleg.
It's one of the black-tailed deer's 5 specialized skin glands, and it is also the most obvious and complex.
The organ is a thickened patch of glandular skin, covered with coarse bristly hair, and each hair has an unusually large arrector pili muscle.
The skin of the organ is deeply embedded with sebaceous and sudorifierous glands, meaning it produces BO's dynamic duo --sweat and sebum (or skin oil).
The skin of the organ is deeply embedded with sebaceous and sudorifierous glands, meaning it produces BO's dynamic duo --sweat and sebum (or skin oil).
The arrector pili seem to control the dissipation of the scent. When they contract they probably squeeze the glandular products to the surface. By raising and flattening the hair they also likely control the dissipation of the scent.
Black-tailed deer aren't alone in having tarsal glands. White-tailed deer, caribou and their domesticated relative, the reindeer also have them, as well as the Latin American brocket deer. They seem to be a communication mechanism that evolved in the New World deer (elk, with their roots in the Old World, lack them).
The glands are variously developed in each of these species, but all of them hunch awkwardly and pee on their glands while rubbing them together.
This rub-urinating is a visual and olfactory signal to other deer. Black-tailed does prolong urination when rubbing. Rather than let it flow, they dribble.
My masters advisor, Dietland Muller-Schwarze observed fawns to spontaneously rub-urinate soon after birth, and in response to separation from their dams. It seems to serve as an olfactory separation signal.
He also saw it in aggressive encounters, when it follows lateral displays of competing bucks. This often leads to increased distance between rivals.
Rutting bucks, especially older ones, spend so much time rub-urinating that they stain their legs.
Like an overworked and unwashed kitchen sponge, the sweaty, oily, urine-soaked patch of hair is an ideal fermentation site. What's more, the hairs are specialized to hold the secretions -- hence the term osmetrichia.
The fermenting mixture clinging to those hairs makes for a potent brew.
Words can't do justice to the smell of the tarsal organ. Let's just say it is strong, but not a particularly unpleasant odor (if you're a mammalogist).
Karl Miller and his graduate students conservatively identified 34 species of bacteria in the tarsal tufts of white-tailed deer.
Does had fewer bacteria than bucks, and only one kind of bacteria was exclusive to does. Bucks on the other hand had nine exclusively male bacteria.
The relative abundance of bacterial species also differed among individuals, which means that the tarsal tuft's odor and its intensity may very well give each animal it own BO signature.
Supporting this view is the observation that all deer of all ages indulge in rub-urination.
Miller's group suggested that heavy staining of the legs below the gland may result from higher levels of steroid excretion in males. One bacteria, Corynebacterium xerosis -- the same one that produces human underarm odor -- is known to convert odorless steroids in apocrine (=sweat) secretions into smelly ones.
It stands to reason that white-tails may be able to detect one another's dominance rank from the intensity of the sex hormone metabolites in the tarsal organ.
Miller has taken it a step further, suggesting that all that bucks' glandular secretions and pissing may affect the reproductive cycle of the does they court, possibly by accelerating estrus. Pheromones of other mammals are known to synchronize estrus or cause abortion, so why not deer? It's a subject ripe for study.
References
Alexy, K. J., J. W. Gassett, D. A. Osborn, and K. V. Miller. 2003. Bacterial fauna of the tarsal tufts of white-tailed deer (Odocoileus virginianus). American Midland Naturalist, 149:237-240.
Gassett, J.W., K. A. Dasher, K. V. Miller, D.A. Osborn, and S. M. Russell. 2000. White-tailed deer tarsal glands: sex and age-related variation in microbial flora. Mammalia, 64(3):371-377.
Miller, Karl V. The White-tail's signature -- the tarsal gland.
Muller-Schwarze, D. 1971. Pheromones in black-tailed deer (Odocoileus hemionus columbianus), Animal Behaviour, 19:141-152.
Quay, W.B. and D. Muller-Schwarze. 1970. Functional histology of integumentary glandular regions in black-tailed deer (Odocoiileus hemionus columbianus). Journal of Mammalogy, 51(4):675-694.
Thursday, March 12, 2009
An issue of paternity
They were an unlikely couple.
A good-looking, outdoorsy and free-spirited female, and an insecure gray-haired homebody.
He cut a farcical figure in his raincoat, but he could cock his leg with the best, and faithfully sprinkled his territorial stumps.
The relationship worked.
Years passed without issue. Then suddenly last fall it happened.
Roxie got in the family way.
It was a joyous occasion, except for Moe.
He didn't need a DNA test to tell him something was wrong.
The kids didn't look like him. It was hard to take.
In due course, the kids moved on. Except Fred, the one that looked like a Lab.
He moved down the hill, not as far as Moe would have liked.
He kept coming back to bully his mom, play fetch, and eat Moe's food.
It was a hurtful reminder. Moe wanted to kick the silly kid's ass.
But he always showed restraint. Moe was a gentleman.
Wednesday, March 11, 2009
Bobcat medley
[75 yards from the house; 1:30 AM, March 8]
Pulled cards on 6 cams this weekend and had a good run on bobcats.
[looks like the same cat in the same place; 2:50 PM, Feb. 25]
You can just make out the spots on the back of the ears. They can only be seen from the front when the cat is crouching in defensive threat with ears laid back. The cat blends well with the dead leaves.
[Marin county, 1:11 AM, Jan. 23.]
This one looked oblivious to the camera.
Compare the leg bars on this cat and the next one.
Spotting of the forebody and barring of the forelegs differ in each cat and are more easily distinguished between cats than patterns on the sides and hindquarters.
[same trail; 6:56 PM, Jan 30]
The size of those ears tells me this one is a young adult. There's something in the stance that says "cute little kitty". It also seems unaware of the camera.
Tuesday, March 10, 2009
Fred finds carrion
[the bone is at his feet -- it's a toothpick in his mouth]
Fred gave me that look of arrested intent.
He knows I become unpleasant when he eats turkey turds.
He has learned to look for approval before eating or diving into anything smelly.
This time he got praise. He found his first carrion yesterday -- a sour smelling leg bone. Deer. Probably tossed out the window of a poacher's pickup.
"Gooood boy!" I gave him a dog biscuit.
Then I let him do his thing.
The old carnivore neck-slide and roll.
We were both pleased with his smelly find.
Monday, March 9, 2009
Exposing the stripper
She was naked and alone. A redwood sapling stripped of her outer bark.
The question was who was the stripper. Chickadee, titmouse, bushtit? Maybe a nuthatch. Or was it a rodent?
I suspected a dusky-footed woodrat. There was a stick nest only yards away.
Rich thought maybe a Sonoma tree mouse.
We set the camera about 12 feet away and 5 feet off the ground on a metal post, and we waited 6 weeks for a good weekend to make the four and a half hour drive, which was last Saturday.
The camera batteries died after a month, but there were 52 pictures.
Forty four were of grey squirrels and twelve of them were of squirrels on the tree.
There was one visit by a woodrat.
And 4 of deer, who looked only to be passing through..
The evidence is inconclusive. None exposed the stripper.
We'll have to use video to catch it in the act.
The work never ends.
Thursday, March 5, 2009
The creeks are gushing
We're catching up on rainfall out here, but we're still short of the mark.
A somber state hydrologist on a Sacramento TV station said we're still in a drought cycle. The reservoirs are filling slowly, because the land is still soaking up the water.
Today Fred and I visited three unnamed seasonal creeks that tumble down the slopes of Butte Creek Canyon. The water is crystal clear, even though the creeks are gushing.
And I was surprised to find newts breeding in such swift water. Most of these creeks dry up by June, but a few remain as pools fed by springs under the capstone.
And I was surprised to find newts breeding in such swift water. Most of these creeks dry up by June, but a few remain as pools fed by springs under the capstone.
Fred fell in out of concern when I stepped on onto a rock in midstream, but he's half lab and still smelled quite doggy when we got home.
It was a good day. I found two excellent sites to set camera traps in the coming weeks.
Tuesday, March 3, 2009
I finalized my notebook
Since my last post on record keeping, I decided I needed a customized logbook for my 2009 field records.
This layout, done on my computer, works for me well. It cues me to record the data on the spot. When I get home and want to update my spreadsheets, all the information is there.
If I have just a few new sets, I don't have to hook up my GPS to the computer. I just enter the GPS waypoints from the notebook on a topographic quad using MacGPS Pro, and I see where I was.
If I want to upload tracks or a large number of waypoints, then I cable the data from the GPS to the Mac.
I settled on a format that allows me to record up to 4 sessions at a camera trap set. If it's a really hot set, I can continue sessions to a new page.
I also included several calculations. They give me access in the field to success rates and pictures/day at different sets -- a chat topic that may come up during a break or lunch.
For reference I have a calendar and a list of my cams on the inside of the back page.
My camera traps are a mixed bag that use anything from 2 D cells to 6 NiMH AAs for external power. I use the camera list to figure out the number and type of batteries to take when I go to check cams.
Oh yes, after I printed the pages, I trimmed them with an xacto knife, and stitched 18 double-sided pages together in a single signature. The cover is a recycled file folder.
Very satisfying for an old codger who has plenty of time and not much money.
Sunday, March 1, 2009
A clear day, another set
[Fred next to camera set #219]
It's raining again, but I am not complaining. We had a few warm clear days, and yesterday I set another camera trap about 2.5 miles from the house.
When it comes to setting up cameras, Fred's an absolute nuisance.
He barks at me, removes things from the rucksack, pulls at the cable when I'm attaching the camera, mounts me when I am adjusting the camera's view, and runs off with the GPS when it is averaging locations.
It's the kind of frustration you curse about and then chuckle.
While this particular site offers little in the way of scenery, it is situated at the edge of a narrow ridge where animal trails converge from both sides.
Ponderosa pine, oaks and mazanita -- good edge habitat.
I dabbed some coyote anal gland scent on the base of the tree. Fred was on it like stink on a skunk.
On the way back I stumbled upon this old scat.
Whatever left it--puma or coyote--it was eating deer. Fred stepped on it and didn't even notice. But he can find and tries to eat every turkey turd in the woods.
[This is the camera's view. I previsualize each set as stage where the animal will make its appearance. I want the animal to pause in front of the ponderosa.]
I dabbed some coyote anal gland scent on the base of the tree. Fred was on it like stink on a skunk.
On the way back I stumbled upon this old scat.
Whatever left it--puma or coyote--it was eating deer. Fred stepped on it and didn't even notice. But he can find and tries to eat every turkey turd in the woods.
Labels:
animal scat,
camera trap sets,
puma scat
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