For what it's worth, I've found both Oliva sayana and several species of Olivella active during
daylight hours in Florida's coastal waters.

Marlo

Howard L. Clark or Kate Clark wrote:

> Gijs said:
>
> < As far as I know, both Olivella and Oliva are buried
> beneath the surface during the day, and only emerge at night
> for foraging.>
>
> Not in this part of the world, where at least Olivella
> semistriata, Olivella columellaris, Olivella volutella, and Oliva
> undatella are abundantly (or even massively) active in the
> daytime.
>
> kate