Blennies displaced by  are able to find their way back to their original hole, so  they likely do sometimes leave their holes to explore their territories. They are opportunistic feeders, preferring to dart out quickly and retrieve food bits from the water column, as opposed to engaging in active foraging and hunting behavior.
The passage describes how blennies, when displaced, can return to their original hole, suggesting they may venture out to explore their territory.  They are known for being opportunistic feeders, meaning they prefer to quickly grab food items from the water column rather than actively hunt for prey.