What is my clown doing?

[disciple]

My black ocellaris is making a small crater in the sand. I have had her for at least 5 years and never saw this type of behavior before. I did introduce a male percula or ocellaris, that she seems to like, a few months ago. Is she getting ready to spawn or just mated pair behavior?

 

[jmadden]

I have a similar questions as well. My pair of clowns do something similar. The male will do what is described above by disiple.