As we pursue the sport we love, we often place ourselves in hazardous situations. The Santa Cruz Fly Fishermen Board supports an informative corner to sharpen our be smart and safe behaviors.
Hypothermia
By Kent Hull
Hypothermia
By Kent Hull
Each of us has likely seen articles describing hypothermia and how important it is to avoid it. This one describes risks we club members face on typical fishouts and what to do to reduce the risks.
Monterey Bay: Sea surface temperature in the bay rarely climbs above 60¡F. If you end up in the water, your "duration of useful consciousness" is less than four hours according to U.S.Navy guidelines. This means that even if you are wearing a PFD (life vest) that will keep your face out of the water when unconscious, you could easily die unless you are gotten out of the water and warmed up within a few hours. Navy flight crewmembers are required to wear exposure suits when out of gliding range of land whenever the sum of air and water temperatures is 120¡F or less or the water temperature is 60¡F or less. A wet suit offers protection similar to an exposure suit, but I don't know anyone willing to wear one while fishing on the bay. What is the likelihood of being found in time if you go in the water? Very poor unless you have some kind of signaling device or stay with a capsized boat, and someone knows to look for you immediately. It is nearly impossible to find a person in a PFD in the water otherwise. I've spent dozens of hours in a helicopter searching for men overboard or downed aircrews to no avail unless they used signaling devices or they stayed near wreckage.
What should you do to protect yourself? Only go out when:
* you can stay in radio contact with another boat reasonably close by (within a mile or so) and you have arranged to look out for each other;
* you wear a PFD at all times with a good signaling device attached (best is something that makes colored smoke; a signal mirror is good only if you're close enough to another boat to see it when you're in the water, and the sky isn't overcast; a strobe light is useless in daytime and not great even at night).
These guidelines also apply in other large bodies of water where you are too far from shore for you to swim out of the water. How far this is, is highly variable, depending on your own stamina as a swimmer, wind and cold.
You are also at risk simply being in an open boat in cold rain or wind. You must protect yourself from getting wet and have outerwear that protects your whole body from rapid heat loss to wind. Your unprotected head can be a major source of heat loss, and a baseball cap is inadequate. If you start to shiver and don't have warmer gear to don, head back in immediately.
Float Tubing. We rarely float tube in safely warm water.
* If you ever get cold enough to start shivering, get out of the water and get warm. Shivering is usually your best warning of the onset of hypothermia. Your heat loss may be from inadequate insulation under your waders or, more likely, inadequate insulation of your head and upper torso. You can always take off an excess layer or a too-warm cap. It's very difficult to get the extra layer you need from your truck when you're in the middle of Crowley.
* If your waders start to leak noticeably, get out of the water, get into dry clothing and get warm. Once you get insulating layers wet inside your waders, you will lose heat rapidly.
* Especially in rain, snow, or cold air, simply getting out of the water is not enough. You must conserve and restore body heat. Getting indoors or in a warm vehicle is best; wrapping up in a space blanket will do, especially if you have an insulating blanket underneath. It's not easy to use a fire to get warm unless you're also sheltered from wind.
Wading. The biggest risk of hypothermia is loss of heat to cold wind or through rain-soaked outerwear. Taking a dunking is a problem if you can't get your hat and jacket fairly dry or if you persist in fishing with wet insulating layers inside your waders. Once you start shivering you must head for shelter and dry clothes. If your outerwear protects you against rain and wind, walking should keep you warm enough to reach shelter, but only if you don't dally for just one more cast.
Hiking, or Just Being Out There. No matter what you're doing out-of-doors, if you start to shiver, do something about it. You're not going to get any warmer unless you put warmer clothing on or get to a warmer or more sheltered area. Even evaporation of perspiration from a burst of activity can chill you. This is especially insidious at higher elevations such as Mammoth Lakes where water evaporates at a much lower temperature.
Summary. You are at risk for hypothermia year-round in most of the places you fish. To protect yourself you must both take measures to avoid it and to recover from it if avoidance measures fail. You can die from hypothermia and each year unprepared people do.