Human shields

You've heard me say it here before. When the puma's image appears in my local camera traps the local black-tailed deer seem to spend more time lingering in the neighborhood gardens and driveways. The observations could be a coincidence, but maybe something else is going on. The puma, for example, could be following the deer, or the deer could be using the proximity of people and large dogs as a "human shield", a place where human disturbance is more likely to discourage most predators.

Well, Joel Berger of the Wildlife Conservation Society recently published a interesting example of how human activity affects wildlife ecology in wilderness areas. During the ten-year study, Joel showed that the moose in Yellowstone and the Grand Tetons adjust their use of space in relation to human infrastructure and activity.

Specifically, he found that over the years radiotracked moose have moved closer to roads at calving time. During the birth season, deer in general become secretive and restrict their movement to a very small portion of their home range. Since grizzlies feed on moose calves, but avoid roads in places like Yellowstone and the Grand Tetons, they are less likely to encounter this brief but nourishing windfall. The evidence suggests that moose and other prey species find humans more benign and at certain times gravitate to human-modified lanscapes for safety. People just don't tolerate predators as well as they do prey, and thus they create safe havens in the vicinity of buildings, roads, and campgrounds.

Good work, Joel (and send me a reprint, please!)

Revenge of the otters

Butte Lake Campground, Lassen National Park:

The grandkids were swimming at Butte Lake when I overheard the camp host mention otters to a family near by. It piqued my interest, and later that afternoon I was lucky enough to engage the host as he was making the rounds checking camp sites.

"I overheard you mention otters today down at the boat launch. Are they stealing fish?"

"No, but we had one bite a swimmer here on the 4th of July. He was checked in right here at this camp site." Small coincidence.

The victim, I learned, was a young man in his thirties, who had planned to spend a few days at Butte Lake with his wife and 8-month old baby. They arrived at 5:00 that afternoon, unpacked, and went to the lake for a swim. The husband swam out about 100 yards, while mother and baby waited on the beach. Then he turned around and headed for shore. His wife saw the otter swimming towards him when he was about 50 feet from the beach.

It was NOT a member of the local welcoming committee. The otter sunk its teeth into the man's upper calf, and worked its way forward, biting him above the elbow, on the latissimus (under the arm), and twice on the face below the eye. I gathered that the body bites were on the right side, and the facial bites were on the left.

So much for a happy family camping trip. They left at 8:00 that evening, and headed for the nearest hospital in Susanville, an hour and a half away. The face bites required 11 stitches, and the doctors started rabies inoculations. One aggressive otter curtailed a three day camping trip to 3 hours, and the National Park Service posted a warning.



Apparently otter attacks are becoming more common in the US, and the most likely explanation is that human recreation is becoming more common in otter habitat. Otters are highly territorial and don't tolerate the intrusions of neighboring otters. Thay also have strong maternal instincts. So it is NOT unnatural for a mother to defend her youngsters against large swimming mammals that splash about and make loud noises. To a wild otter people can be scary as hell.

Perhaps that's what happened at Butte Lake. The otter birth peak is in March and April, and the young aren't weaned for another three months. This puts the mother and her mobile but inexperienced youngsters in the water in June and July, when they forage together as a family. You can expect such mothers to be protective.

That would explain the other July otter attack in the Sierra Nevada and one that took place in April when an otter attacked a crew team on the Connecticut River.

More difficult to explain however are otter attacks on pets. One would expect a territorial otter to drive a frisky lab out of the water, but wildlife biologists scratch their heads when an otter attacks and drowns an Eskimo dog. Is this normal behavior? Have they been eating bad (=chemically contaminated) fish? Or are they suffering from rabies?

Inevitably the call goes out to remove the animals.

Which raises the question. Where else but in nature do we punish healthy maternal instinct?

As this codger sees it, if you you want to live close to nature, be prepared for the risks. Isn't it better to be bitten by an otter than the Taco Bell chihuahua?

Urban Coyotes: Update

The Golden Gate Park coyotes that were shot last week for acting like coyotes were quite possibly parents.

A 5-month-old coyote was hit by a car near that busy stretch of 19th avenue that snakes through the park.

Shortly after the park walker found the carcass he also saw one or possibly two live coyotes of the same size.

The heavy hand of natural selection is again thinning the park's coyote population. Time will tell if the survivor(s) have the right stuff to survive in the city.

I'll keep you posted of any further developments.

On river rovers and camp raiders

You're looking at a true river rover. This raccoon plys the river banks and shallows in the summer. It doesn't depend on people for food, though it won't hesitate to feast on their leavings -- fish guts, unused bait, and junk food. Its usual diet is revealed in its scat -- crayfish and aquatic insects, with occasional frogs and fish. In the winter and spring, when the creeks are in spate, I imagine it works the uplands for food.

That raccoon came to a set I made on a cobble bar in Butte Creek, a couple miles from my house. It's down there behind the boulder in that patch of willows near the left hand bank.



The only human habitation in the area was a "California fixer-upper" tucked in a gulch between the PG&E flume and the creek. Finding prime riverfront property for a bargain $999,999 was an unexpected surprise.



Okay okay, I'm pulling your leg. It was an abandoned miner's shack. There's a spillgate on the flume up the hill from the shack, and a sign intended for latter day sourdoughs, hikers, and codgers like me. It informs you that the gulch below the flume could flood from diverted water at any moment and without warning. (So much for gold miners and common sense.)

The prospect of a deluge didn't worry me either, but the presence of miners would have sent me packing. The beer cans however were old, so I knew they hadn't been around for a few years.

I climbed down to the creek, found the cobble bar, and put a tablespoon of "predator stink" on a rock, thinking a family of otters would show. No such luck. Six days passed before the coon waded out to explore the smelly rock. It sniffed it and was gone in 23 seconds. I got 4 rather disappointing pictures.



Raccoons are comfortable city and town dwellers, which may explain why they don't visit my camera traps. Why wander the chaparral and ravines for slim pickings when the neighborhood offers a smorgasbord? The two settings breed different kinds of animals--the trim retiring river rover you see here, and brash rotund coons of city, town, and campground.

Back in the 80s we had an amusing experience with Minnesota's camp raiding coons. It was late August and we were on the long trip home from Glacier National Park. The girls and I had just pitched our tents in Itasca State Park, and the redhead was dutifully starting dinner. Our rations were low. I had been advised to stop at a grocery store, but we were "in the boonies", and none turned up.

My wife didn't buy my feeble excuse, ("I guess Norwegian bachelor farmers grow everything they eat."). I was informed that men couldn't take directions, and as a consequence we would be eating leftovers.

Normally this wouldn't be bad news. The redhead is a gifted chef. But we were down to a plastic bag of limp carrots and a can of refried beans. As she scraped black spots from the carrots, my daughters protested, "Mo'om!".

Then the wonderful aroma of barbecued chicken wafted into our camp.

"You know, sweetie, one of these times we should splurge and buy some chicken or steaks. These Minnesotans know how to do it up right." It was a wistful thought, and the girls chimed in their endorsement.

As we basked in the bouquet of sizzling chicken, and forlornly anticipated our own humble meal a great howl of pathos rose from the neighboring campsite.

I mosied over to find 4 large raccoons on the picnic table amidst a mouthwatering repast of barbecued chicken and corn. Grandma and mom were unceremoniously crawling into their tent and commanding the kids to "Chase them away".

"We can't", answered big brother who was about 12 years old. "They're too big."

As the coons feasted, the brother and his two younger sisters gave a blow-by-blow account. They were just like sportscasters, and the ladies lamented each call.

"They finished the chicken, mom."

"Oh, my God." came the voices from the tent.

"Grandma, they're eating your cake!"

"Oh, my God," they grieved again, "not the cake!"

And so it went.

Shortly after the drama ended we ate our refried beans and limp carrot sticks, and the raccoons ignored us completely.

"You know, there's something to be said for keeping it simple," I mused.

The redhead remained silent.

Urban coyotes

There was a flap in San Francisco last week. A pair of coyotes living in Golden Gate Park had a territorial dispute with a couple of leashed Rhodesian Ridgebacks. The authorities decided there was a clear and present danger to pets, and the two coyotes were shot. There was a hue and cry from both sides of the fence, but coyote sympathizers seem to be in the majority.

Coyotes have been reclaiming parts of San Francisco for several years now. They trickle in from the thick coastal scrub south of the city in the San Bruno Hills and San Mateo County where they have always lived. Wildlife biologists estimate there are less than a dozen urban coyotes in the city. The best coyote habitat is Land's End -- the steep cliffy area beyond the Golden Gate. The Presidio, McLaren Park, Lake Merced, and Bernal Heights also have their wild patches and a few coyotes too.

More recently at least one pair of coyotes took up residence in Golden Gate Park. The park has plenty of food. There has always been a bountiful population of brush rabbits and pocket gophers, and the house mice used to breed by the bushel when the mounted police composted hay from the horse stables. It also has a lot of people

Until now the coyotes have been good citizens. Though they were frequently spotted by park visitors, they kept a low profile, didn't sing, and fed on local game. But apparently they became fed up with canine intruders. A steady procession of bizarre-looking dogs visited the park with their owners. Some looked like food, some looked like rivals. To the coyotes they were fair game.

The ill-fated pair was most intimidated by the Rhodesian Ridgebacks. They were three times bigger than themselves, and they stirred the purest of canine emotions -- deep passionate blood red aggression. So they attacked the ridgebacks. The melee was just a dogfight, but it freaked out the owner and injured one of the dogs. (It needed stitches) The next day (last Sunday) a dog walker showed up on their turf with two Jack Russell terriers and 2 bigger dogs. The coyotes showed "culinary interest" in the Jack Russells, but the bigger dogs chased them off.

The die was cast. That night the authorities (USDA Animal Control specialists) lured them in with a predator call, and shot them with "a small hunting rifle".

Officials observed that coyotes are normally retiring around people, and that such bold conduct is uncharacteristic.

This is true, but these coyotes couldn't really get away from people, could they? If they didn't adjust to people, they would have stressed out and lost it. If a muni bus didn't get them first, they would have died with adrenal glands the size of tennis balls.

The problem is this: the songdogs had flouted a cardinal rule. "Always keep your distance from people and their pets. The pooch may look like food, but don't go there. And don't eat garbage. It may smell good, and it may be easier to find, but gophers and rabbits are better for you.

"Remember that human society is hard to fathom. Dogs may fight each other, chase cats, bark at the moon, and eat garbage, but don't kid yourself. You are not that kind of dog. For you the rules are different.

And nature lovers, there is a message here for you too. You may have and enjoy your urban "yotes" as long as they live by the rules. Even in the great city of St. Francis, bad coyotes must die so good coyotes may live.

It's part of the evolutionary play. In a few decades, your grandchildren will feed urban coyotes just like the pigeons at Union Square. By then they may even do a few tricks for a handout.

As for me, I'll take the wild coyotes with all their faults.

Yosemite's scrofulous cadgers

That's him, next to the squirt gun. We're talking about the California ground squirrel, Yosemite's scrofulous cadger.

His life seems to be an obsession with junk food. If his cute squirrelly presence doesn't seduce you into tossing him a handout, he has no qualms about taking it from your plate, car, backpack or sleeping bag. When he needs a fix of corn chips and bean dip, he'll go to any length to get it. Like junkies anywhere his personal hygiene leaves something to be desired. If you think all ground squirrels look slightly raunchy, just hike into the high country and check out their svelte cousins there. A diet of seeds, gooseberries, bark and the occasional bug makes a world of difference.

Before continuing, however, let me commend the National Park Service. Despite modest increases in federal funding in past years, the park service has carried out its mission exceedingly well. And it has done an excellent job of notifying us of the consequences of feeding wildlife. It has appealed to our common sense ("feeding wildlife can be dangerous"), to our sympathy ("feeding wildlife is bad for their heath"), and to our fear ("feeding wildlife can expose you to disease"). But the task is overwhelming, because most campers can't help themselves. They seem to leave a trail of food wherever they go. So, the park service invests its greatest effort in protecting visitors from bears, and protecting bears from visitors.



If you don't believe it, just leave your salt shaker, an empty pop bottle, or a bag of chips on your camp table. Mr. Park-Ranger-Man makes his rounds after you've turned in, and it doesn't matter what you are doing in there. He'll provide the lighting and wait patiently for you to put the food in the bear-proof locker or trash can.

But rodents are a different matter. The park service simply warns you in advance not to feed them, and then lets the rodents put you to the test.

We had our test last year. Our group came prepared to fend off the cadging rodents. We already knew that it was impossible NOT to feed them. There was always the occasional fallen chip, or the misplaced dish of snacks to give them hope.

So a few anonymous members of the group decided that a squirt gun or two would not only discourage the rodents, but also provide them with a much needed bath. Mind you, this is frowned upon by park management, and I certainly don't endorse or recommend it, but a drama of man and beast inevitably plays itself out in the campground. (And let me add that I use the term "man" advisedly, because few women in campgrounds do as many stupid things as men.)

Well, no sooner than the snacks and libations started to appear so did the squirrels, and with a little practice the marksmen were spot-on target. It was great sport, and a highly entertaining diversion. But the squirrels were really pumped from eating the junk food. Even as the stream of water drew closer, they kept eating at high speed, and when the water hit its mark, they merely scampered beyond the circle of people, and took a hurried dust bath.



Then the muddy rodents made a diversionary circuit behind the tents, and appeared unexpectedly in our midst ready for the next round.

Well, when happy hour came to a close, a few human casualties were almost dry, and the squirrels seemed to have gone to bed. The ladies laid out a splendid assortment of salads, pasta, baked beans, assorted vegies, and grilled meat. A couple more bottles of two-buck Chuck appeared, and we filled our plates. Then we settled down to enjoy the repast. By now, as they say, we weren't feeling any pain. The hikers' aches were gone, the conversation was flowing, and we dined in a spirit of conviviality.

Then one of the ladies got up to refill the wine glasses, and we heard the anguished cry. A scrofulous cadger was on the table, sitting in the casserole, enjoying the pasta. There was a great hue and cry, the men took up their arms, and the food was sprayed with water.

The squirrel seemed to know we'd lost our edge. A few minutes later he was discovered once again in the casserole dish. He had obviously been there for a while and looked rather bloated, but he made his exit unscathed.

Hunting pumas with kindness

Dr. Rob Horwich of Gays Mills WI just responded to the previous mountain lion blog:

"I recently heard about that lion attack and another where a mother defended her 7-year-old against a cougar for an hour. I think California should institute the old cougar hunts with dogs (but in this case the "hunts" should be non-lethal). I think that would probably give the mountain lions some fear of humans. In Belize the mountain lions are described as "upstart", but they are smaller in Belize, and I am unaware of any attacks there. By the way, I recently heard about a huge pack of 53 squirrels bringing down a cougar, so once again nature establishes a balance."

Horwich’s "benign hunting" idea has merit. Use aversive conditioning to change the puma’s minds from ‘people are prey’ to ‘people are scary’. If the idea conjures images from Stanley Kubrick’s screenplay of Anthony Burgess’s "A Clock Work Orange", allow me to reassure you. We’re suggesting a kinder and gentler aversion therapy than that.

Here’s my take on it. First, consider an area where wildlife biologists deem people to be at high risk of attack by pumas. The hypothetical area has a known population of pumas, a low population of deer, and is frequently used by hikers, mountain bikers, and joggers, who occasionally report sightings of prowling pumas. Maybe harmless puma-human encounters have already taken place. In other words, the clock is ticking.

Responsible wildlife authorities would be scientifically prepared for the undertaking. They would have baseline information on puma-human encounters, and an index of puma abundance based on indirect census methods, such as counts of sign and camera trap records. Next, the wildlife biologists would stage mock hunts. Winter might be the best time. That’s when puma mothers teach their cubs to hunt. The hunters themselves would be professional wildlife biologists, and they would track the lions with hounds until treed. Have you ever seen a picture of a treed puma? Their body language tells it all. If you will excuse my anthropomorphism, they wear a look of terrible humiliation. After a few unpleasant encounters the sight and sound of people and dogs will give pumas what we Californians call "bad vibrations".

If the method works, pumas would avoid rather than stalk people. In any event, the field surveys would give quantitative measures of success or failure. In other words, if the cats avoid the area and puma sightings decline, we could consider the method successful.

Having worked for the government for many years, I know that bureaucrats usually do not cotton to really good hare-brained ideas. So I would anticipate two kinds of responses. The "argument of personal responsibility" would maintain that the hiker who is informed and cautious about pumas is a safer hiker.

Good bureaucrats also use more than one excuse. The coup de grace to the well-intentioned but misguided suggestion is the "argument of fiscal limitation". "Your suggestions, while interesting and of possible utility under specific circumstances, are not feasible for economic reasons." This is usually followed by a litany of statistics about the department’s enormous scope of responsibility, low staffing levels, and equally important competing needs. Your hair-brained idea is dead meat.

So, let "benign puma hunts" increase departmental revenues. It could be tastefully done. There would be no shortage of well-heeled Silicon Valley naturalists who would pay big-time to tree a puma and shoot it (with a camera). Hey, aren’t Apple’s latest operating systems named after the big cats? What are we waiting for? Thar's gold in them thar hills!

When a mountain lion attacks

My heartfelt sympathies to the Hamms, who fought off a mountain lion attack last week. The couple’s chilling description of the ordeal and their determined defense has inspired a great deal of interest and compassion, not to mention lame rhetoric and political commentary. Fortunately, Mr. Hamm is on the mend, after a turn for the worse due to infection. The Hamms have always enjoyed hiking in wild places, and I hope they won’t give it up after this experience. But if they do, so be it. You can’t really blame them.

California’s wildlife advocates invoke changing demography to explain the increased frequency of mountain lion attacks. It stands to reason. The state’s landscape looked a lot different in 1849 when a very sick wagon train captain named J. Goldsborough Bruff (1804 - 1889) decided to call it quits. He dropped out somewhere in Lassen County, wintered in a shanty, and kept a diary. His account gives perspective on what it was like when wildlife outnumbered people. Bruff ran out of food, but the native Yahi offered no succor. Nasty encounters with a steady stream of unsavory fortune seekers had already taught them to keep a low profile. He resorted to scavenging the carcasses of abandoned oxen and big game killed by wolves, grizzly bears, and mountain lions. The predators didn’t leave much meat, but he lavished praise on the choice broth he concocted from the boiled bones. No doubt wild game outnumbered people one hundred and fifty years ago. There was even enough carrion around to support a population of condors. Bruff knew—he shot one.

Long gone are the wolves and ‘grizz’, but the California Department of Fish & Game estimates we share our state now with as many as 6000 mountain lions. And the census takers tell us the golden state has 35 million people. (It’s easier to count people.) The place is changing in other ways. Most of the quaint towns of the coast range, foothills, and Sierra Nevada have given way to burgeoning suburban communities. San Francisco’s bay area baby boomers have migrated to the foothills and beyond into the Sierra Nevada, so a lot of people now live much closer to nature. Mountain lions and other predators must see or encounter a lot more people than in the past.

There’s a clear and present danger when large predators encounter people more often than their normal prey, and this might have been the case with the lion that mauled Mr. Hamm. Cal Fish & Game officials killed a pair of mountain lions near the site of the mauling, and identified the female as Hamm’s attacker. Mountain lions are solitary, which means the female was with her offspring or was having a fling. Either way, two cats get half as much to eat when they make a kill. To eat normally they have to kill more often.

When something like this happens, I get a lot of free advice from family and friends. Normally they view my camera-trapping sorties into the woods as harmless eccentricity. In the wake of near tragedy they behave like officials of the Occupational Health and Safety Administration (OSHA). I can’t defend my outings with the old arguments about probability—"I’m telling you the odds are better of getting hit by lightening than killed by a puma."

But I don’t really want to tempt fate, so I have to consider the expert advice. Don’t go into the woods alone. Carry a big stick. Don’t run when you see a puma. Make your self look big. Etc. Neighbor Richard advises me to take a sidearm, preferably a double action .38 caliber. Professor Wolfgang Schleidt, my grad school mentor in ethology tells me to carry a black umbrella. (Indeed a 19th century German explorer crossed Africa unscathed by flashing open his umbrella at all threatening beasts). And why not don a crash helmet and neck brace? Pumas invariably attack the head and neck.

I am trying to heed the advice of family and friends. My daughter bought me an air horn, and my cautious wife advised me to take the walkie-talkie on my outings—not that anyone could ever find me should I send an SOS.

So a few days ago it was again time to check the trap line.

"Sweetie, how about a hike down in the canyon this afternoon? Two is safer than one, right?"

"You walk too fast. And with my luck the puma would attack me, the slow weak one. Take the walkie-talkie and the air horn Lauren gave you".

I arm myself with a big stick, the walkie-talkie and the air horn. I leave the other walkie talkie in the kitchen. With my knapsack on my back, I head down into the barranca—"valderee, valderah, valderee, valderah ha ha ha ha ha….",

Safely at destination, I drop my knapsack, and pull out the walkie-talkie to report to home base.

"Okay sweetie (puff puff), I’m here at set 21. . . the mossy rock--where I got the puma pictures. . . Do you read me?"

The walkie-talkie goes "Blurp", and there is silence.

"Okay sweetie", I repeat, "I’m here. . . are you there?"

Another blurp, another silence.

Back at the house, I query my beloved whether she heard me calling, and she answers, "No, I was in the computer room.

"Well, what if a puma had attacked me."

"If the puma attacks call when I’m in the kitchen."

My wife is a practical woman.