While likely safer than a walk in an urban park, Mount Diablo area wildlands have their own special hazards.
Dehydration is probably the most commonly encountered hazzard of our wildlands. You may be suprised to know that the risk of dehydration can actually be high on a cold winter day. This is because as the air is warmed in your body its capacity to hold water vapor greatly increases. This causes increased transpiration of water from your body. It is a good idea to "tank up" on water before your hike, since if you feel thirsty you are significantly dehydrated. Heat stroke is the most dangerous consequence of dehydration and can be fatal.
We will only be concered here with plants that are dangerous to touch, assuming that you won't be eating any wild plants or fungi that you are not absolutely sure about (collecting specimens is generally prohibited in areas covered by these pages).
Of course, our California favorite is poison oak. It contains an irritating oil that can be transfered from the plant to a pet or clothing and on to affect a person that did not even go near it. Some people have an extreme alergic sensitivity to it while others may be barely affected. If you know that you have come into contact with poison oak, the recommended treatment is to wash any affected skin as soon as possible with soap and cold water. Be aware that poison oak in winter has no leaves (just twigs) yet is still toxic to the touch. In certain areas it can grow low and close to the ground within the grass and so get onto your ankles if you are not protected.
Resembling a thistle, this will leave tiny stinging cells, similar to those on a stinging jellyfish, imbedded in your skin.
Burrowing animals often dig hazardous holes in roads and trails.
Avoid disturbing the local pit viper, the Northern Pacific Rattlesnake. These can vary in color from brown and tan to black and white and are marked with patterns similar to their more famous cousin, the Diamondback Rattlesnake. These venomnous snakes are primarily identified by their flat, arrow shaped head. The pit viper's head contains pits located on a line between the nostrils and eyes. These are the snake's infrared heat sensing organs. Rattlesnakes may (or may not) have rattles, which are remnents of previously shed skins. These may be lost and so should not be used as an identifying feature if not present.
Rattlesnakes are generally docile and nonagressive, being most interested in killing animals that are small enough to eat whole, such as mice, lizards, ground squirels, and (in the case of large snakes) rabbits, and then only when they are hungry. Rattlesnakes don't like surprises or teasing and that is when you might get bit. Since they do not move much and are well camoflaged the best defense is to simply keep your eyes open and watch where you step (and if climbing, where you place you hands). When climbing, never place your hands on a ledge that you cannot see unless you can first sweep it with a stick or other device.
Keeping your eyes open and moving cautiously is the best way to see wildlife of every kind.
The most dangerous rattlesnake is a young one, for they have not yet learned to conserve their venom. There are other snakes in our area that you may mistake for the rattlesnake, the gopher snake and the king snake. These snakes suffocate their prey by constricting them with coils of their body and are not dangerous to humans, although if provoked they may bite. Their head shape differs from the rattlesnake. Please note that harassing any wildlife in any way is prohibited in our wildlands. For additional information on the habits of rattlesnakes click here.
For Pictures of the Northern Pacific Rattlesnake, click here.
For Pictures of the Pacific Gopersnake, click here.
For Pictures of the California King Snake, click here.
This snake is NOT Dangerous, but if sighted and accurately identified, please report the location of this endangered species to a qualified naturalist. There are also common garter snakes of similar appearance but with different colors. This is a rare and endangered species that should not be disturbed unless it is in danger.
For Pictures of the Alameda Whipsnake, click here.
If you are challenged by a mountain lion, do not run away. This can trigger a chase and kill reflex in the animal. The best defense is to stand still and look as large and threatening as possible. If you have a jacket on, unzip it and wing it out to form a large silohette. Wave your arms slowly.
Resembling a large and chunky short tailed housecat, a healthy Bobcat will usually avoid you. Consider yourself lucky if you see one. If you have a dog not on a leash your animal may be sufficiently fast and agressive to get into trouble. If you cannot rely on your pet to respond to voice commands under all contitions, keep it leashed. Dogs are prohibited on hiking trails and fire access roads in Mount Diablo State Park but are allowed if leashed in campgrounds and parking areas and on paved roads. See the Mount Diablo Page for specific information concerning pets in this park.
Any wild animal that is willing to approch you, or let you get close, or a normaly nocturnal animal out in the day (skunk, raccoon, porcupine, bat, or opossum) may be infected with rabies. This is an extremely dangerous disease and it must be treated before symptoms appear. It is transmitted from saliva to blood, usually with a bite, but can be transmitted from dead animals through a cut or sore. The treatment itself is painful and dangerous but may be avoided if the offending animal (dead or alive) can be examined and is found to be free of rabies.
The best way to avoid these is to not sit on grass or bare ground and to avoid contacting brush and tall grass. If you have been hiking trough heavy brush or grass, the best defense is to undress in your bathtub and carefully brush and inspect your clothing and yourself.
Lyme Disease is caused by a microcopic spirochette, similar to that that causes syphilis. The desease is progressive and debilitating but can be treated with modern antibiotics. The deer tick can be as small as the head of a pin. The immediate symptom of an infection is a red ring two to three inches in diameter (5 cm to 8 cm) around the bite site, with a more pale central portion. Subsequent symptoms in a well established infection include lethargy and aching joints. Some people have been infected unknowingly and due to improper diagnosis have suffered unecessarily.
Bubonic Plague is endemic in some parts of California, being hosted by ground living rodents, but is seldom a hazzard to people if the precaution of avoiding ground contact is followed. Like Lyme Disease, this is also treatable with modern antibotics.
In our area, the likelyhood of being bit by an infected mosquito may be small, but since a mosquito bite can cause an irritating red welt, it is best to be defensive anyway. A good repellent can be used if you plan to be out in the evening in an area where mosquitos are prevelant. Although certain of the local mosquitos are capable of transmitting malaria, there is no local wildlife hosting these organisms. Both Western Equine Encephelitis and West Nile Virus can be very dangerous to humans. West Nile Virus, which is hosted by birds, has now been found in southern California (August 2003) and is expected to be endemic in this area in 2003 or 2004. The wild host of this virus is birds, so if on your hike or elsewhere you encounter a dead bird that is not obviously the prey of a raptor, this should be safely collected without contact in a plastic bag and reported to your local desease vector control as described on the CDS website This is especialy important locally in the late Winter through early Summer seasons if West Nile Virus has not yet been reported in that area.
Although some local mosquitos can vector the Malaria parisite, there is no wild host for this in the United States or Canada.
Unless you are severely alergic, a single sting should not be life threatening, but being a puncture wound there is some risk of infection. If you are stung by a bee, the barbed stinger, venom gland, and pumping muscles will be left at the sting site. Quickly remove this by scraping in the drection the bee was facing when stinging. This must be done as quickly as possible. If you can do this within less than two seconds of the initial penetration you will reduce the amount of venom injected. If done within half a second the injection will be greatly reduced.
At the time of this writing these bees are only found in the southernmost portions of California, but are expected to be in the San Francisco Bay area within the next few years. Foraging africanized bees are no more dangerous than other bees. They are extremely dangerous if they perceieve danger to their hive and perhaps also when swarming. They are known to pusue intruders up to 1/4 mile. Individual bees are no more dangerous than other bees - it is the large numbers of stings that they can inflict that is dangerous.
This is our most dangerous spider in terms of the damage inflicted. The bite can cause the death (necropsy) of surrounding tissue. Its reclusive habits make contact unlikely unless you are disturbing its habitat. Most encounters occur when moving woodpiles or inspecting crawl spaces under buildings
A bite from this spider can be painful and even debilitating for a period. Similar in habits to the Brown Recluse.
Generaly considered harmless, the males of this large and beautiful spider is frequently seen in our local wildlands in September and October, when leave their burrows to search for a mate. Leave them alone as they can inflict a painful (but not usually dangerous) wound if provoked.
If you have comments or questions, mail me with subject "WildHike" at the address shown below in the graphic (this is to foil spambots, net spiders that collect e-mail addresses for mass mailings). Note that our politicians won't stop spam (they could) - why not? $$$