Fake users signing up

I created a new install - and it is not being marketed or mentioned on the net yet - but it seems I am getting a ton of fake user registrations where they all have some type of spam in their user profiles mentioning various sites to visit.  For example:


Telephone: (07) 4078 9265

About me

Not much to say about me really.
Enjoying to be a part of this site.
I really wish I am useful in one way here.

my web site - dau bao tu


How can I stop this?  Im getting a bunch every day.