Hi there! I'm new and at my area aren't many active members so I had an idea to help making BC more popular. There are some open bookshelves around here. Could I just grab all of these books and write a small note with the bcid in it? Or is it considered rude since they technically aren't my books?
If the book-swap shelves have an owner - like a Little Free Library manager or the staff of a school or hotel where they're located - you could talk to them first. They might be interested in doing BookCrossing themselves!
If you do want to register them all, I'd agree with Camperfan's suggestion to replace them with books of your own during the process - or at least take only a few at a time. (When I take books from book-swap shelves, I always include the location in my journal entries - and a photo, if I can get one. )
One mild caveat: this activity might help spread the word about BookCrossing, but I have noticed that I get fewer journal entries from books on book-swap shelves/OBCZs/LFLs than I do from books left on park benches, statues, or trees. So register books, by all means, but don't be disappointed if you don't get immediate JEs.
You may have already planned this, but the way I'd recommend you proceed would be to release your own books at as many of these book-swap shelves as you can, in and around your immediate area - and on more far-flung ones if you take any road-trips. The release notes will put the release locations on the "go hunting" pages, making them more apparent to any local BCers or those passing through.
books take a while to be journalled. But most do eventuallly!
That's not technically true. I know my catch rate is not among the highest, but I'm only at about 6% for wild catches and about 25% for controlled releases. And I've been releasing for 15 years, so even the stragglers have had time to write home.
At one point the site average was said to be about 10 - 20% get journaled. I don't know if that has changed and if there are more up to date site totals.
Personally, I don't think BookCrossing would be nearly as much fun if every book got journaled right away. The interest is wondering which book released on which date at which place will decide to write home. Getting the rare catch then becomes exciting.
[Which is not to say that I don't love getting catches, I really do, but I recognize that it involves a lot of luck and serendipity, as well as sufficient clear labeling, to hear back from our books.]
You already registered the book, I presume. Each book gets registered only once, but hopefully will be journaled by those that find it later.
If someone does make a journal entry you will be notified by an email to the email address you signed up with. And then you can do the Happy Dance. [Getting your first catch is VERY exciting!]
You should know that being a BookCrosser requires patience and the ability to let your books go. They'll write home when they're ready. But you can hope that they have found a loving home with a new reader even if you don't hear back right away. Good luck!
I have released a few hundred, some I did mark as a wild release others just as traveling and I have only had a few journaled on. I have seen people actually pick up and take my books before since I was at botanical gardens at the time and wandering around and no journals. One time at the same garden for an event I just happened to have 2 kids books with me that I was planning to leave somewhere but noticed a vendor had her 2 kids with her so I actually handed her the books so her kids had something to do while sitting around and never got a journal on them. So it is nice when a book I leave in the wild gets journaled on.
As to the OP, since I am not exactly sure what you mean by an "Open shelf" if its a shelf like in a hotel or some other establishment maybe talk to whoever runs the place first to make sure its ok , but I wouldnt see a problem really. If it is an offical bookcrossing zone that is set up somewhere, normally there is a sign saying it is, and you see any unregistered books then feel free to go ahead and register them and leave them.