Pacific Crest Trail: Northern California. Jeffrey P. Schaffer
not one tenth the fear but with twice the ferocity of a southern Secessionist.” So wrote William H. Brewer about his evening in Yosemite National Park’s upper Lyell Canyon on July 1, 1863. This statement is still very true for most of the High Sierra, for Lassen Volcanic National Park, and for the Klamath Mountains. Still, trekkers may encounter mosquitoes even in southern California, and wherever there is a water source suitable for their breeding. They can be quite abundant along the Sacramento River, which you encounter at a low elevation in northern California’s Castle Crags State Park. Mosquitoes occur near water from sea level up to around 11,000 feet, that is, near treeline. All mosquitoes can transmit various diseases, but those found along the PCT rarely do. Only females ingest blood, and their biting and buzzing are more of a nuisance than a health hazard. By late July the mosquito populations wane in the high mountains, as snow melts and meadows dry out (although they can still be abundant lower down, where water is available). Until then, you’ll probably want to carry a tent with mosquito netting just to get a good night’s sleep. This is especially true in June. From midmorning until late afternoon, when you are likely to be on the trail, a wind usually keeps their numbers down. Of course, you can postpone your hike until August, but this is not an option for through-hikers. Mosquitoes are pollinators, which explains why they are near their maximum numbers when wildflowers are so profuse. Without them, perhaps mountain wildflower gardens would be less glorious.
Flies can be a problem at lower elevations. Small black flies typically become numerous in warm weather, that is, from about June through early October. One favored habitat is among shady canyon live oaks, which can be locally common in southern California. They are attracted to sweat from your face and body, but if you clean up, the flies generally cease to bother you. Occasionally at low to mid elevations you’ll meet large, biting flies, usually deer flies, but they don’t attack in numbers. Furthermore, when one is preoccupied biting into your skin, it is easy to swat.
Mosquito
Tick
Another problem is the yellowjacket, a wasp that occasionally builds a ground nest under or beside a trail; if you trample on it, the yellowjackets will swarm you. You are very unlikely to meet them, though your chances increase if you ride a horse, for it tramples the ground far more than a hiker does. Their stings are multiple and painful, but not dangerous unless you happen to be allergic to bee stings. (More people in the US die from bee stings than from rattlesnake bites.)
One of the best arguments for avoiding squirrels, which frequent popular campsites looking for food, is that they may be rabid or their fleas may carry the plague. This is extremely unlikely, but small areas of plague-infested rodents are occasionally found in the mountains. Avoid fleas by avoiding rodents.
Ticks, the slow-moving relatives of spiders, are another potential carrier of disease. These blood-sucking arachnids are usually found in brushy areas below 6000 feet in southern California and below 4000 feet in northern California. Check your clothing and skin for them after you hike through brush at low elevations.
And finally there are scorpions, which are not merely desert creatures. You may find them in southern California up to about 7000 feet and in northern California up to about 5000 feet. These creatures, active at night, can give you a painful sting, although the species found along the PCT are not life-threatening.
Rattlesnakes
Few animals are more unjustly maligned in legend and in life than the western rattlesnake, and no other animal, with the possible exception of the American black bear, causes more concern among walkers and riders along the California PCT. Indeed, most through-hikers will have 5-6 encounters with these common reptiles by the time they reach the High Sierra! Even so, the author knows of only one PCT hiker who was ever bitten.
Frequenting warmer climes generally below the red-fir belt (although they have been seen much higher), rattlers will most often be encountered basking on a warm rock, trail or pavement, resting from their task of keeping the rodent population in check. Like other reptiles, rattlesnakes are unable to control their internal body temperature (they are “cold blooded”), and therefore can venture from their underground burrows only when conditions are suitable. Just as rattlers won’t usually be seen in freezing weather, it is also no surprise that they are rarely seen in the heat of day, when ground temperatures may easily exceed 150°—enough to cook a snake (or blister human feet, as many will learn). One usually will see rattlers toward evening, when the air is cool but the earth still holds enough heat to stir them from their lethargy for a night of hunting. They naturally frequent those areas where rodents feed—under brush, in rock piles, and at streamsides.
It is their nocturnal hunting equipment that has inspired most of the legends and fears concerning rattlesnakes. Rattlers have heat-sensitive pits, resembling nostrils, in their wedge-shaped heads that can sense nearby changes in temperature as subtle as 1°F. Rattlers use these pits to locate prey at night, since they do not have well-developed night vision. More important perhaps is their sensitivity to vibrations, which can alert a rattler to footfalls over 50 feet away. With such acute organs to sense a meal or danger, a rattler will usually begin to hurry away long before a hiker spots it. Furthermore, if you do catch one of these reptiles unawares, these gentlemen among poisonous snakes will usually warn you away with buzzing tail rattles if you get too close for comfort.
Like many of man’s pest-control projects, efforts to quell rattlesnake populations have been to our detriment—rattlers are invaluable controllers of agricultural pests, and fewer people are hurt each year by rattlers than by household pets. One unsuccessful program carried out in the 1960s eliminated the conspicuous, noisy rattlers and left the silent ones to breed. A population developed in which the snakes would strike without buzzing. Luckily, most rattlers encountered along your PCT way will gladly move aside without incident.
The easiest way to avoid a snake bite is to avoid snakes. Over 75 percent of rattler bites are in people who are handling a snake, and over 80 percent of all bites are on the hand. The lessons: don’t catch snakes, and look before you put your hands under rocks or logs, or into tall grass. Snakes will usually graciously depart as you approach, if you make enough noise—a good reason to carry a walking stick.
If bitten, get to a hospital immediately. The only truly useful treatment for rattlesnake bite is intravenous antivenin, which can be administered in most emergency departments. The sooner it is given, the better, even if you must hike a distance for help. If you are part of a group, have the victim rest, while another hiker goes for help. Because antiquated first-aid measures such as cold packs, tourniquets, and incision and suction devices are dangerous, they should never be used. There is no substitute for rapid evacuation to a hospital.
Mountain Lions
These large cats, also called pumas or cougars, range up to about 200 pounds for males, about half that for females, and they strike fear in many hikers. There seem to be two views about how threatening they are to humans. One is that they are merely curious, and that is why they track you. The other is that they are hungry, and that is why they stalk you. In California, an attack on humans by cougars is a rare occurrence. Certainly if they wanted to, cougars could easily kill you, best while you’re asleep, tent or no tent. To my knowledge there has only been one incident on the PCT, when in March 2001 a mountain lion attacked a hiker on the Mt. San Jacinto section.
Before the mid-1990s, cougars were hunted throughout the state, which kept their numbers down and gave them a fear of humans. With the hunting ban, their numbers are increasing and they may lose this fear. As urban areas sprawl into their territory, they sometimes take pet dogs (just as coyotes take pet cats). You are not likely to have a close encounter with a cougar, although one may get close to you. If the trail tread is soft, look for its tracks: paw prints about 3 inches across, like those left by a large dog, but without claw marks, since cats walk with retracted claws.
Since 1993, the Park Service in Yosemite has been warning visitors of increased lion sightings, and rarely, dogs, left alone in the park’s campgrounds, have been attacked. For hikers, here is amended advice