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38

How much sea water can I safely drink? = None If you drink sea water, how much fresh water do you need to drink to off set the sea water you drank? = 2.8 units of distilled water per 1 unit of sea water (to neutralize without adding hydration) The "scientific" answer to this question involves a lot of complex math, human physiology and significant ...


25

Good hygiene is a highly subjective benchmark. Clean enough for comfort might be different than clean enough for company. Ocean water, albeit salty, is water. You can bathe with it, wash clothes with it, wash dishes with it etc. Soap behaves differently (the surfectants don't suds as well) but you'll still get things cleaner than they were. As for bathing, ...


25

Let's say you lose 2 liters of water per day. To replace 2 liters of water by eating fish, you need to eat, for example, 2,500 g of cooked Pacific cod, which, besides water, also contains 500 g of protein and 3.4 g of sodium. Consuming 3.4 g of sodium (8.5 g of salt) per day is not that much; some people consume it on a daily basis. I calculated (from here) ...


24

Theoretically, it might be possible to survive on fish, rainwater and desalinated seawater. In one 1930 experiment, two men survived for a year eating exclusively meat without experiencing any health issues. This indirectly suggests that meat (and therefore possibly also fish) contain all the essential nutrients, but this was a small and relatively short ...


24

There are a few possibilities: Other Turtles This site about pet turtles mentions the possibility that turtles fighting over a mate (or actually mating) may end up on their backs. When breeding season comes around, adult male turtles might start fighting over the females. A stronger male might flip a weaker one over. Male turtles might also harass ...


23

If you run out of fuel, have engine trouble, run aground soft, when there is no immediate danger to the marine environment, the boat, or the persons on board, then towing is just towing. If a vessel is hard aground, stranded, on fire, or sinking, and is towed from the site, it may be considered a salvage operation. This once meant a reward of a portion of ...


22

They are wave crests. It's wind folding over the top of waves, which mixes them with air. They're also called white caps. If they're closer to the shore you have a change of water color to a lighter blue. That lighter blue could mean there's coral below or a shallow bottom. Waves do not move fast. They're more like a drum in the water slowly rolling forward, ...


21

If you don't know what your boys are capable of then it's unfair to have expectations. I'm a Venturer Scout adviser for Scouts Canada; I take boys in that age group on trips regularly. I don't know what your group is like, but if it's anything like mine, then the boys probably all have different levels of ability, strength, and skill. For trips like this ...


20

I think Wikipedia article on Fjard has a very good explanation: Although fjards and fjords are similar in that they are a glacially-formed topography, they still differ in some key ways. Fjords are characterized by steep high relief cliffs carved by glacial activity and often have split or branching channels. Fjards are a glacial depression or valley that ...


17

Early this year I crewed on a yacht that was crossing the Atlantic and all of the crew were doing this for the first time. For our leg from Lanzarote to St Lucia we had 1,000 liters of fresh water in the tanks and this with careful use would last for 30 days for a crew of five. So from a practical experience I can answer some of the questions based on our 26 ...


17

Walk backwards. The fins will have the least trouble with the water if you walk backwards.


16

You need to distill it - I'm assuming that freezing is not an option (unless you're camping in the extreme latitudes). This is easiest, as the ice on top is almost pure water. Where you don't have a freezer available - boiling the water, capturing the steam and condensing it back to water will provide pure water.


16

Here's what I normally take with me on these trips at the moment. I can divide them into what's needed before, during and after an incident. Avoiding trouble clothing and food (including drink): as with any outdoor activity, it's important to avoid fatigue and hypothermia. Poor decision-making is the start of most problems, and reduces your ability to ...


16

The best answer I’ve come up with so far is to combine neoprene paddling gloves such as those sold by NRS with an additional pair of waterproof or semi-waterproof mitten shells designed to be worn over gloves / mittens. This has kept my fingers completely comfortable in air temperatures well below freezing while paddling through rivers or bays where ice is ...


15

Set the anchor by reversing the engine until the anchor chain is tight, and then run the engine at medium speed to make sure the anchor has dug in. You can watch a GPS to make sure the speed is around zero (and the anchor is not dragging) when you're doing this. However, if the tide and/or wind changes, it can pull out a set anchor. If you use a LOT of ...


15

Yes. My wife is a geologist and has been on a couple of research cruises in the south Pacific and Indian oceans. It used to be quite common to have a "swim call" when the seas were calm. The vessel would stop, and the crew and scientific staff would go for a swim. In one case a student lost her leg to a shark during a swim call on a NOAA ship. I believe that ...


15

They are Sea Urchins and they taste like mussels. People mostly eat them raw. They're actually pretty tasty. Oh yeah, you'll peel off the shell and go for the slimy flesh, a delicacy with fresh lemonjuice and a pinch of salt. I used to pick them open with my pocketknife and slurp them up with some saltwater (depending on the sea it's probably not the most ...


14

Seawater is not itself sterile, in fact, it has all kinds of organisms. Salt in a wound is likely to hurt, and saltwater won't be a particularly effective antiseptic. With wound cleaning, it's always a question of trade-offs. It might be better to use less-than-sterile water to clean an extremely dirty wound if infection is otherwise inevitable. However, ...


14

I haven't been paddling much for several years, but I used to go all winter with simple fleece gloves inside waterproof dishwashing rubber gloves. I tried a half dozen other alternatives, including wetsuit gloves, other waterproof gloves, pogies, etc. Fleece insulation and waterproof outside worked best, and was also very inexpensive.


14

... can someone gather/hunt/farm all of the nutrients required to be healthy whilst never having to land again? Nutrients yes, healthy not likely. A 1000 days is a grueling journey. Reid Stowe, whom used to have a website called (Beyond) 1000 Days at Sea: The Mars Ocean Odyssey, lived at sea (without contact with land) for 1,152 days (equals 3 Years, 1 ...


13

This is highly dependent on the type of water as well as the location, but I'll summarise a few things to be aware of. In many locations most of these dangers won't factor in, but they're useful things to bear in mind if you're trying to assess the danger of a particular body of water. I'll focus on the sea here - for other things such as rivers similar ...


12

My mother suffers from every form of travel sickness, and the only solutions she has found that help to ameliorate the symptoms (if not actually remove them entirely) are: Drugs: specifically Stugeron Bracelets: I am a bit skeptical of these, as is Skeptics.SE, but they seem to work for her. Example here If I feel at all queasy in really heavy seas (ie the ...


12

Typically, if you are out in the open ocean and do not have a GPS device you don't have any useful way to measure velocity* This may not be a problem though, as what you are wanting is not your velocity, but an indication that you are heading in a straight line to the destination (if we assume a constant current) To do this, what you need is something to ...


12

First things first you aren't going to be able to get longitude without an accurate clock and/or a tome of sight reduction tables. Without those aids which you'd be hard pressed to create while marooned on an island your navigational options are limited. The best you can really hope for is to follow a latitude line/plane. I think a cross staff would be an ...


12

No, gulls (of some species at least) steal food from other birds by moving them until they drop it. They must then be adept at snatching the falling food in mid air. There's material of interest in the Wikipedia article on seabirds - search for kleptoparasitism, reference 23 looks particularly interesting. The article on mobbing also hints in this ...


11

On water, you can use the curvature of the earth to help you, and change your height instead of moving. According to the Boat Safe Kids web site, the formula for how far away the visible horizon is over water (in other words, how far you can see) is 1.17 * sqrt(eye height in feet) = (distance in miles) While wikihow says sqrt (1.5 * eye height in ...


11

What you're seeing is a huge washing up of tuna crabs, Pleuroncodes planipes, which has created "red beach" all up and down the California shoreline, as well as other states. It's not an uncommon occurrence farther South, and is quite frequent in Baja and along the Mexican coast. There are some interesting scientific theories as to the cause, the changing ...


10

What xpda writes about setting the anchor is right (although hopefully you know this if you are sailing your own boat). As well as what he says, make sure you have the right kind of anchor for the bed, and you have enough rode (rope or chain). For overnight it should be at least 7 times the water depth. The longer the better, within reason. Here are some ...


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