Blackspotted rockskippers (Entomacrodus striatus) avoid refuges with conspecifics

Area of Science:

• Behavioral ecology
• Marine biology
• Animal behavior

Background:

• Animals often require rapid refuge selection during predator evasion.
• The blackspotted rockskipper (Entomacrodus striatus) is an amphibious fish inhabiting intertidal rocky areas.
• These fish exhibit unique jumping behaviors between terrestrial and aquatic refuges.

Purpose of the Study:

• To determine if Entomacrodus striatus prefers unoccupied refuges over those occupied by conspecifics.
• To investigate the influence of conspecific presence on refuge choice in this species.

Main Methods:

• Laboratory-based experiments were conducted to observe refuge selection behavior.
• Fish were presented with a choice between occupied and unoccupied refuges.
• The number of trials where fish chose occupied versus unoccupied refuges was recorded.

Main Results:

• Entomacrodus striatus significantly preferred unoccupied refuges, choosing them in 11 out of 14 trials.
• Occupied refuges were still utilized in 3 out of 14 trials, indicating they are not entirely avoided.
• A strong avoidance of occupied refuges was observed.

Conclusions:

• The study suggests that Entomacrodus striatus actively avoids refuges occupied by conspecifics.
• Chemical stress signals from resident fish are hypothesized to be the deterrent.
• This avoidance behavior likely plays a role in predator evasion strategies.