very good photos, they are hard to catch.
The first crab is a ghost crab and they mainly come out at night, that's why they have large eyes.

The little one is a bubbler crab. when you walk on the beach you will notice little dot patterns like sand art.
This is them, when the tide goes out, they dig their way out of the whole and as they do this they eat and roll the sand into balls and place them around making patterns.
When the tide comes in they hide in the hole and it closes. When low tide comes they start over again.

Like your work black. wolf i'm out of steem again sorry.