Algorithmic behaviour and spatial memory are used by two intertidal fish species to solve the radial maze

Area of Science:

• Animal behaviour
• Ecology
• Marine biology

Background:

• Rocky-shore fish face challenges in locating food in dynamic tidal environments.
• Efficient foraging requires strategies to avoid depleted food sources.

Purpose of the Study:

• To investigate the roles of algorithmic behavior and spatial memory in foraging efficiency.
• To compare these strategies in fifteen-spined stickleback (Spinachia spinachia) and corkwing wrasse (Crenilabrus melops).

Main Methods:

• Utilized an eight-arm radial maze to test foraging behavior.
• Manipulated the presence or absence of spatial cues (colored tiles).
• Introduced delays within trials to assess memory retention and algorithmic reset.

Main Results:

• Both fish species developed an 'every third arm' algorithm in the absence of spatial cues.
• Spatial cues largely replaced algorithmic behavior, indicating reliance on spatial memory.
• Memory retention was estimated between 0.5-5.0 minutes, fitting tidal cycle timescales.
• Foraging efficiency was impaired by random repositioning of cues, supporting the spatial configuration hypothesis.

Conclusions:

• Spatial memory plays a crucial role in foraging efficiency for these fish species.
• The spatial configuration hypothesis better explains how fish utilize spatial cues for memory.
• Foraging strategies are adapted to the rapid environmental changes characteristic of tidal habitats.