Etiquette for hikers in Yakushima

This sign means you can
use your toilet pack here;
but you cannot throw it
away here!

World Heritage status brings both pride and concern to the residents of Yakushima. The people here are known to be friendly and open, but also have a deep sense of duty and responsibility rooted in harsh terrain and unforgiving weather. In fact, many businesses are hesitant to except foreigners, because they are afraid that they cannot handle the responsibility. What if you get caught in the rain because you misunderstood the bus-stop? What if you have trouble eating Japanese-style food or using a Japanese-style toilet? What if you take a wrong turn in the mountains because the sign is in Japanese? What if an emergency occurs and they don't know how to give you necessary instructions? In big cities, you are expected to fend for yourself, but it's different in rural areas where it's custom for people to look out for each other. In fact, the biggest thing you can do to ease interactions for future visitors is Stay Safe:

1. Always let someone know where you are going and do not cancel reservations without notification.This should be obvious anywhere, but on Yakushima, how do we know if you are lost in the mountains or just out drinking?
2. Do not try the most difficult trails first, especially if you are hiking alone. Most people I talk to find that hiking here takes longer or is more difficult than they expected.
3. Watch the weather forecast and/or ask if your plans are okay given the anticipated weather. Have a back-up plan in case inclement weather holds you up. In extreme winds, ferries and planes may even be cancelled.
4. Plan to arrive at mountain shelters during daylight hours, especially if you are not carrying a tent. Safety aside, you will disturb everyone who has already settled down for the night. Also, during high season, the shelters can fill up fast.

Additional Hiking Etiquette:
Half of my job as a hiking guide is to take care of my clients, the other half (the half they don't pay me for) is making sure they aren't a nuisance. The following guidelines are printed numerous places in Japanese, but for some reason they never got around to the English:

1. Buy and use a disposable toilet pack. Honestly the Japanese don't even do this, but it's a big problem because urine does not evaporate in 100% humidity. Before gaining World Heritage Status, hikers were expected to do it naturally, but things got quite nasty. Moutain toilet facilities were not designed for current loads, and the contents of shelter toilets must be carried down manually. Do you really want to make someone else carry your crap?
2. If you use hiking poles, put rubber caps on the ends to protect the environment.
3. Do not throw out anything along the trails. From spitting out toothpaste to cleaning dirty dishes to dumping half a bottle of sports drink or throwing out orange peels.
4. Do not inadvertently feed the animals buy leaving food (and tobacco!) products where animals can get to them.
5. Do not smoke around others on the trail. On the route to Jomon Sugi you can smoke at designated spaces at the 1) the trail head, 2) behind the shelter in Kosugidani Village, 3) next to the toilet at the end of the railroad tracks, and 4) by the toilet at the hut beyond Jomon Sugi if you make it that far. In Shiratani, there is a smoker's alcove above the toilet in the parking lot.
6. Understand what it means to share narrow trails. On your return hike, yield to hikers on their way up. If the trail is crowded, keep members of your party close together. Watch that you aren't blocking the trail.
7. Do not eat your lunch or sprawl out for a midday snooze at crowded spots where people are trying to take pictures. (Wilson's Stump, Taiko-Iwa, Jomon Sugi)
8. Stay on the trail. This is both for safety and preservation. 
9. Don't load up on stinky sunscreen and bug spray if you don't need to. You'll probably want sunscreen if you are hiking on a sunny day in the interior mountains, but for areas like Jomon Sugi, Shiratani, and Yakusugiland, the forest canopy provides natural sunscreen equivalent to something like SPF 30. If you're hiking with bug repellent, wait until you see biting bugs (black flies, horse flies, mosquitoes) before applying it.
10. Pay park entrance donations. (Yes, I know there back routes into the parks. Access is not restricted because it is assumed you wouldn't try to bulk the 500 yen entrance donation.)
11. Treat the land with respect. These are sacred mountains. Since ancient time, before this island was scarred by logging and codified by World Heritage status, people have been climbing these mountains to commune with the gods.

Sea Turtle Etiquette:
Sea turtles may be large, but they are easily disturbed and scared. Especially during nesting season (Late April~July) and hatching season (through the end of summer), please take care when visiting sandy beaches. :

1. Do not walk near or in front of mother sea turtles. Stay out of sight at least until mothers finish digging their nests.
2. Do not use lights near turtles that have not finished digging their nests and do not use flash photography.
3. Watch where you step when there may be babies on the beach. At the same time, you don't want to confuse them by shining a flashlight away from the ocean.
4. Give sea turtles priority. It's nice to walk on the beach at night, but during season, the turtles need their space.

If you'd like to see the sea turtles laying their eggs, or the young clutches scrambling down to the waves, but you don't know how to act around them, just make a reservation at the Nagata-Inakahama Sea Turtle Museum. There are other beaches where you can also see them, but please do so under the guidance of local residents. And before you go, how about reading up on proper behavior:

   http://www.seeturtles.org/859/sea-turtle-nesting-beaches.html

   http://www.heronisland.com/Turtle-Watching-Guidelines.aspx

Etiquette Around Town:
Money: Know that only a few establishments are prepared to except credit cards. Pay at the front in restaurants, and expect to pay in advance at small accommodations. Do not try to change bills larger than 1,000 yen on the bus. Do not tip, although an offer of gas money may be appreciated if you happen to catch a ride.
Rain: Check that your backpack cover isn't full of water when you board the bus. To avoid mold, try not to leave wet things lying around your hotel room. For your own sake, you may want to bring a second pair of shoes to use when your hiking boots get muddy. It's perfectly fine to ask to borrow an umbrella.
Standard Japanese etiquette: Of course I can't list everything here, but you probably know to wash before entering the baths and ask permission before taking photos of other people.
Peculiar to Yakushima: Wear a towel but not a bathing suit at Hirauchi Kaichu Onsen or Yudomari Onsen.  Do not kill spiders: They are the protectors or the island. Stop by an information booth if you would like to go over your itinerary when you get to the island. They may not speak great English, but they try to be of great assistance. And if you have any problems during your stay, let the folks in the information booth (not the Information Center; that's a private company) know.

No matter what activities you engage in, please also remember that this is the land of the gods, not some place to show off your machismo.