The Deer and Puma

At the moment five deer are pawing snow looking for acorns next to the house. Not far from the bird feeders. I can watch them from the kitchen window. They also enjoy browsing the herb garden, but that's under a snow drift.

Of course, there are no pumas in sight, but I know they're around too, as you'll soon see. 

Occasionally female pumas make forays into our community on "the ridge" in search of Mr Right. The caterwauling of a lovesick lady puma is a wonderful sound, but it rouses the dogs to bark up a storm, and it makes the neighbors a little testy. 

My advice to my neighbors is step out the back door and enjoy the dogs sounding off in sequence as Ms Lonely Heart moves away. Rest assured that an estrous pussy cat isn't interested in eating.      

 

Bears on the puma kill

After filling its stomach with one haunch the puma left and never returned. But 4 bears came to feed nightly and eventually a few other scavengers made their appearance.

Murphy's Law struck on the second night when the camera failed, but this whipped me into overkill mode. On each following night I staked two or three cameras. Each one operated independently and triggered one or two 27 watt LED lights.

I was learning on the run. When all cameras were in operation too much light marred some pretty cool clips. All I could do was adjust the position of cameras and lights every afternoon based on the previous night's results. I just didn't have the moxie to test the lights in darkness.

Then Murphy's Law got me again: the camera that gave by far the best clips in terms of lighting and perspective failed to record sound! 

I kept plugging away, and the game was up at the end of the week when the bears lost interest in the scraps.

I had an overwhelming 7 hours of very interesting video of variable quality.

This 3+ minute movie gives you an idea of what happened at the carcass on just one night and the next day.   

Mystery of the Night Flies

When I finally figured out that fast flying bats were causing blank video clips, I started to pay more attention to the insects in my videos.

Soon I noticed that swarms of small flies often showed up when an animal passed the camera.

I wondered if the hungry swarms ever give the critters any peace.

On the other hand, maybe the swarms aren't parasitic insects.

Maybe animals just stir resting flies into motion when they walk by.

I compiled some clips to show you what I mean.

And since I couldn't make any sense of it, I wrote to entomologist Bunyipco (an old friend) for an answer.

He didn't have an answer, and responded as expected of a taxonomist -- "Catch some specimens for identification".

"And how do I do that, may I ask?"

"Simple, hang some fly paper where you see the swarms".

If I post any pictures of bears donning fly paper next year, you'll know what happened.

The carcass disappears

I was absent-mindedly amusing myself, tossing Fred's stick into Hendrick's flume, when I found myself looking at a carcass in the water, a fawn in winter coat.

When I pulled my camera from the bag, I inadvertently flipped my pruning saw into the water, and soon realized that Fred wasn't about to heed my desperate commands to fetch it.

As I watched my saw drift into a riffle I jumped in and rescued it myself.

That's when Fred finally noticed the drowned deer and looked at me as if to say, "What now?"

The carcass was without injuries, but it couldn't have drowned here; it must have happened a few miles upstream where the flume's vertical sides channel much swifter and deeper water.

I heaved it up on the far bank, dragged it into a patch of thimbleberry canes, but decided against setting a camera nearby.  Too many people with dogs.

The carcass was untouched on the following two days, but I assumed it would be gone when I returned from a four-day trip to Mono County with Random Truth and Jake.

Not so. It was still there yesterday afternoon, day seven.

Though unscathed, it had ripened enough to call in a vulture, but the bird hadn't started its work.

Today the carcass was gone, but no scraps and whitewash told of sated vultures.

Fred's carefree approach was soon checked.

He sniffed about cautiously, then stopped in his tracks, raised his hackles, and growled and barked with agitation.

There was no drag trail, and it's my guess that a bear packed it off.

It took seven days for the vulture, and eight days for a bear to find it.

The head on the tree

"How come you're so big but don't have antlers?"

Richard told me he was sure I would have some use for this old deer mount, and I knew there was no way out.

When you owe a very helpful friend dozens of favors you enthusiastically cart off a moth-eaten head mount and find a place to hide it.

I discreetly balanced it on a cob-webby pile of wood working jigs on a shelf above the radial arm saw, and was pleased how well it blended in.

The redhead didn't notice it for about a month.

I sawed off the antlers the other day to make handles on the doors of the pump house, and they look excellent there.

Then I hung the head on a live oak next to the house.

Fred was out of sight at the time, but as I was getting a camera ready in the garage I heard him barking up a storm.

He had discovered the tree with the deer head.

"What is it, Fred?"

Emboldened by my attention he advanced and gave a full-throated train of yodel barks.

When I cautioned "Be careful" he backed off with a sideways glance. (He learned that command with the aid of mousetraps.)

The photos herein are the other two visitors of "the head".

There's no question the young buck is looking at the bulky profile of an unfamiliar buck, but he didn't hang around long enough for a second photo op.

It's hard to say what the gray fox is up to, though he could be sniffing a frayed ear.

Victim of the megaspider

It's frustrating when a giant spider catches your subject matter.

I can usually blame the bear guards, because that rectangular frame of spikes seems to be perfect spider habitat.

In this case however there was no bear guard.

The camera was staked among some ferns on a bank, and the spider also caught several hikers.

I can pnly conclude that the hikers were filling or caused indigestion, because the spider went away.

Friendly face flies of fall

The face flies of summer -- black-tailed deer at Chimineas in September

A warm spell recently summoned overwintering flies from the woodwork, and for several days the redhead wielded the fly swatter with deadly vengeance.  

The autumnal house fly is often found to be the face fly (Musca autumnalis), that nemesis of cattle whose exquisitely designed mouthparts sponge up secretions of eyes, noses, mouths, and wounds, and then stimulate further secretion with rasping prestomal teeth.  

The face fly evolved with the herding ungulates of Eurasia, but not until 1952 did it make its appearance in North America.

Somehow they missed the boat several hundred years ago when the Spaniards brought livestock to the New World. 

But they found everything they needed, multiplied, went west, and reached the golden state in the 1960s.

Face flies have an intimate relationship with eyeworms.

Eurasian and African face flies of several species are hosts of at least a dozen species of these parasitic nematodes of the genus Thelazia.

Adult eyeworms live under the eyelids and in the tear ducts of ungulates.

They lay their eggs in the lachrymal secretions, and the flies lap them up as they feed. 

After hatching the worms develop in the flies' fat bodies, and when about half grown they transfer back to eyeballs, where they cause anything from mild inflammation to conjunctavitus, and even blindness.  

Though the newly arrived face flies were not carrying eyeworms, there happens to be one species of eyeworm native to North America.

Guess where it lives?

Hint: The scientific name is Thelazia californiensis.

Our native eyeworm infects deer, jackrabbits, and coyotes, and sometimes livestock, dogs, and cats.

There are even a few cases of human infection.

Entomologists had long believed that the canyon fly (Fannia benjamini) was the California eyeworm's host, but it really didn't matter because our state eyeworm was economically inconsequential.

That quickly changed when word got out that the face fly was headed west, where wet noses, rolling eyeballs, and drooling lips abound.

If the face fly and our native eyeworm were compatible California's livestock could be in trouble.

Cattlemen started to worry and the state's economic entomologists began looking into the likelhood of an eyeworm epidemic. 

The entomologists examined seventy species of arthropods associated with native mammals, but only a small fraction of canyon flies harbored eyeworm.

Then it was discovered that canyon flies were actually three separate species, only one of which -- an uncommon and apparently undescribed species was the true host of the eyeworm. 

There was a flurry of fly collecting to start a laboratory colony.

"Some dexterity with a net is needed to catch any of these flies . . . , but the vector species seems to be particularly elusive, judging from its behavior in the laboratory."

So noted the investigators, but they prevailed and the elusive new species of fly was bred in the laboratory where it consistently infected domestic rabbits.

With a ready supply of eyeworms and their eggs, the entomologists fed the parasites to face flies with deft and caring tenderness.

The infections didn't take.

Our native eyeworm is highly host specific. In other words, face flies and domestic livestock are not suitable hosts of the California eyeworm. 

Neither are people, most of the time.

But take note dear friends.  Eyeworms will scare away a date faster than any amount of spinach in your smile. 

The take home message is this: "Don't joke about flies or make fun of entomologists."
   

Note: In the absence of voucher specimens I am not sure of the identity of these flies, and for now I will assume they are the common face fly (Musca autumnalis), which winters in homes and buildings.

References

Olroyd, H. 1964. The natural history of flies. Weidenfeld and Nicholson, London.

Weinmann, C.J. et al., 1974. Eyeworms and face flies in California. California Agriculture, November, pp. 4-5.

  

Singles scene at the waterhole

Taylor Spring, August 17, 10:27 PM. 

There's something in the air. The scent of a woman.

On and off he has been tracking her, but he is easily distracted by thirst and good fodder, not to mention other bucks who pause to admire his antlers and spar.

When the acorns drop he'll start to bulk up, and by November he'll reach his fighting weight.

Then the rut will begin.

The annual orgiastic sex-fest is a short-lived phenomenon, and if bucky is lucky he'll only be limping when it's over.

Meanwhile he'll just follow the does, spar with his neighbors, and sample urine spots on the ground.

All for a few moments of carnal knowledge.

A minute later, savoring a urine spot. 

Poison Water guzzlers--black-tailed deer

Three black-tailed deer stepped over the boards to drink in the confined space of the spring. 

The one that caught my eye was this doe.  

She has notched ears, which make her identifiable in the field. 

She also has scars on her neck, and they are not completely healed.

I believe there are two punctures on the left side (the right side of the screen) -- there's a large tear at the base of the neck, and a smaller one midway in the track of missing hair.

The angle of the picture doesn't show the right side of the neck very well.

If there is a puncture, you can't see it. 

The skin was also torn across the neck.  

Here's a different view.

In the third picture, you can see scars on the upper left leg and shoulder. 

Any opinions out there as to what might have caused these wounds?

A good trail

Coyote came down the trail at 7:07AM on March 29

We're in Marin County, and this shady trail gave me a good feeling.

It follows the contours of a steep slope, winding around the bulges and into the drainages, and all the way it climbs gradually.

Here and there the chopped duff shows where animals arrive or leave it for a steeper route to some unknown destination.

There was animal scat too.

So, I set the camera in front of a Douglas fir looking up the path, and a month later the camera confirmed my hunch.

There were 96 pictures of mammals and birds on the memory stick.


Black-tailed deer accounted for 30% of the animal pictures.

The bucks were wearing velvet antlers that looked like fuzzy bratwursts.

Deer mice took second place among mammals (22%).


There was lots of bird activity .

Hermit thrushes were on the trail at dawn or late afternoon.

Together with varied thrushes they were the most frequent avian users (28%), but scrub and Steller jays, a robin and dark-eyed juncos also visited.


Only one raccoon made an appearance,


but bobcats showed up four times.

All were moving up the trail, meaning none faced the camera. (I put out a second camera for the next go-around, and aimed it down the trail.)


And here's the only other coyote picture -- following a shower at 5:15 in the morning.

I had great hope for a camera I set at a coyote latrine about a quarter mile away, but the camera had an electrical short.

After I left that evening, it took 400 photos in two and a half hours -- filling the memory stick. A couple of moths were the only animals photographed.

Proof of the Camera Trap Fairy

There's always a chance that a branch will fall in front of your trail camera and botch the pictures.

Snow can bury your camera for months. Then you won't get any pictures to botch.

In the summer I've had vegetation grow up in front of cameras.

It doesn't take long, but if you wait 4-6 weeks to check your cam, you might find it perfectly camouflaged but still clicking away.

The lens focusses on the plants so you never know what triggered the pictures.



At this set I cleared the foreground of fallen limbs, but twigs dropped over the camera a couple weeks after I left and gave me pictures like the one above.

This was the first time a someone other than yours truly walked by and trimmed the twigs out of view.

Which proves there IS a camera trap fairy.


blac

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 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.

St Elmo's deer

Occasionally you encounter a magical creature . . . like this black-tailed deer with an aura.



Was this yearling imbued with an awesome charisma?



Was it a case of St Elmo's fire dancing over its charged spikes?



Or was it just a spider that crapped on the window over my camera trap's lens?

Cat-licking deer

Would someone out there please lick their cat and tell me what it is like?

The redhead thinks maybe they're salty like a snack food.



I'm grateful to our neighbor Dan who took these pictures in front of his house. As you can see, there is more than one cat, and more than one deer.

In the old days, a graduate student could publish a note on such an observation in the Journal of Mammalogy.

"Feliphilia in male black-tailed deer (Odocoileus hemionus columbianus)"

Those days are long gone.

That doesn't mean there isn't a biological explanation for deer that lick cats.

It's just that nowadays cat-licking deer is a subject more suitable for the blogosphere than scholarly journals.



That is, as long as you don't drag it out.

With that, I've said enough.

Rutting buck

This fellow passed a camera in Marin County.

If you want to read the sprig of willow as a festive indicator of the holidays, it's okay.

To me it shows that he was thrashing vegetation, and advertising his fitness to other bucks and does.

The peak of the rut was back in November. He'll be slowing down and dropping his antlers soon.

Sexy does won't distract him again for many months.

More plank walkers

A raccoon and her family started to cross the plank, but changed their minds and retreated. Another raccoon preferred the creekbed.

Gray foxes were undaunted by the camera. They were in fourteen out of 38 photos at the site.



A pair of them explored the creek bed.



Only one possum was seen scuttling up the trail, barely visible in the distance. I suspect it arrived via the creekbed rather than the plank.

Almost all of the deer pictures were of creek crossers.



Only this buck might have walked the plank.

Having a drink together

Maybe they were buddies when this picture was taken in October, but now the rut is getting underway.

No more are the friendly meetings at the water hole to size up each other's antlers. Now it's all about the quest for carnal knowledge, each buck for himself.

Tanking up

There's not much water around, and the forage is dry.

So the deer have been tanking up at the bird bath. Last night Split Ear arrived first. I saw the camera flash from my desk. He ran when I put the spotlight on him. Broken Antler came a couple hours later.



I top off the bird bath before dark, and it's dry in the morning. These two guys emptied it -- 2 gallons.

Who drinks from the trough?

The answer to the question is not many. Of course I only caught part of the action, because the camera was set for night time photos only.

The pigs came and went. I am sure they could learn to stand up at the trough, but they were drinking from the spring about 50 yards away.

The most active user was this raccoon.



It fished there on several nights, and was quite thorough about it.



The menu was limited -- dragonfly nymphs, smaller insect larvae for sure, together with tadpoles and perhaps a few frogs, though we didn't see any.

Bambi is cute fly bait

Cute, isn't it?

Well, the codger's reaction is less adoration than amusement tinged with cynicism.

Here the log-perching Bambi is displaying the heart-warming curiosity of juvenile deer, a fetching trait that renders it highly attractive as fly bait. In fact, a number of mammals are known to be more vulnerable to parasitic fly infestation as juveniles than as adults.

Entomologist John R. Anderson wrote a fascinating paper about the infestation tactics of nose bot flies that parasitize black-tailed deer. (Unfortunately, I can no longer find the paper among 3000 uncatalogued reprints in the garage, so I am jogging my memory and give you the reference below).

You see deer and cattle share a very long history of relations with various species of bot flies that detect their hosts by very general (e.g. CO2 and urine) and very specific chemical signatures, such as volatile compounds from scent glands.

Out here in the west, two species of nose bot flies infest our black-tailed deer. How they zero in on their hosts isn't well known, but Anderson spent a lot of time watching parasitic flies dupe deer.

One species (Cephenemyia apicata), he found, takes advantage of the deer's curiosity.

The gravid fly chooses a bush in plain view of Bambi, and then buzzes about in a come-hither-come-yon dance. Bambi approaches to inspect this curious thing, and is rewarded with a tiny fly larva squirted onto it's moist muzzle. If the deer doesn't lick and swallow it, the larva wriggles into the nostrils.

Cephenemyia jellisoni, the other species, is a stealth hunter. It approaches the deer out-of-sight and from behind, and slowly moves forward beneath the soft underbelly. Then it quietly hovers into position under the animal's throat and muzzle, taking care to remain undetected by tracking the animal's head movements. When the time is right it dashes into position and squirts its larva ('larvaposits') on the moist lips or muzzle. Numerous females may attack a single deer.

The larvae settle in the pharyngeal pouches at the back of the throat, where they feed on tissue secretions and grow into beautiful bots. (I'm kidding of course.)

I still recall my revulsion the first time I saw nasal bots in the throat of a necropsied deer. We were having a wonderful time being young biologists, measuring testes, preserving uteri, while eating curried venison and drinking beer.

When we started to pull mandibles for aging, there they were at the back of the throat: a writhing mass of inch-long white maggots. We gagged and came close to tossing our cookies, but we were tough.

So I don't turn up my nose to insects. They are here to stay, and when nature pits Bambi against flies there's just not much of a contest.


References:

Anderson JR. 1975. The behavior of nose bot flies (Cephenemyia apicata and C. jellisoni) when attacking black-tailed deer (Odocoileus hemionus columbianus) and the resulting reactions of the deer. Can J Zool., 53(7):977-92.

Anderson, JR. and & W Olkowski. 1968. Carbon Dioxide as an Attractant for Host-seeking Cephenemyia Females (Diptera: Oestridae). Nature, 220:190-191

Cogley, TP. 1987. Effects of Cephenemyia spp. (Diptera: Oestridae) on the nasopharynx of black-tailed deer (Odocoileus hemionus columbianus). Journal of Wildlife Diseases, 23(4):596-605

Olroyd, H. 1964. The natural history of flies. Weidenfeld and Nicholson, London

Tømmerås, BÅ., A. Wibe, AC. Nilssen, and JR Anderson. 1993. The olfactory response of the reindeer nose bot fly, Cephenemyia trompe (Oestridae), to components from interdigital pheromone gland and urine from the host reindeer, Rangifer tarandus. Chemoecology 4(2):115-119