No. You can put in whatever copyright information you wish as long as you are able to be contacted based on that information.
> Does it mean that if someone steal my photo without permission and removed copyright information, other people can just use download it from there and legally use it however they want because they cannot contact me?
Comments
> Does that mean from now on, rather than "Copyright © 2013 Kailuo Wang", I have to say Copyright © 2013 my Email address ?
No. You can put in whatever copyright information you wish as long as you are able to be contacted based on that information.
> Does it mean that if someone steal my photo without permission and removed copyright information, other people can just use download it from there and legally use it however they want because they cannot contact me?
Yes.