The confusion effect when attacking simulated three-dimensional starling flocks.

Area of Science:

• Behavioral Ecology
• Predator-Prey Dynamics
• Avian Behavior

Background:

• The confusion effect, where increased prey group size reduces predator success, is well-documented.
• Research on the confusion effect in coherent animal groups, like starling flocks, is limited.
• Previous studies often used simplified 2D simulations with basic prey movement.

Purpose of the Study:

• To investigate the confusion effect in three-dimensional (3D) simulations of European starling flocks.
• To examine how flock size and density influence predator tracking and capture success.
• To explore the anti-predator benefits of flocking behavior in starlings.

Main Methods:

• Development of a novel computer game-style experiment simulating 3D starling flocks.
• Inclusion of realistic starling movement and flock dynamics.
• Human participants acted as predators to track and 'capture' target starlings within the simulation.

Main Results:

• Predator success rate decreased significantly with increasing starling flock size.
• Higher flock densities were also correlated with reduced predator effectiveness.
• Modelled starlings demonstrated increased safety in larger and denser flocks.

Conclusions:

• The findings support the hypothesis that starling flocks provide significant anti-predator benefits.
• Increased flock density may actively enhance the confusion effect against predators.
• This study provides the first 3D experimental evidence for the confusion effect in avian flocks.