Spatial memory shapes migration and its benefits: evidence from a large herbivore

Area of Science:

• Ecology
• Animal Behavior
• Movement Ecology

Background:

• Animal migration is influenced by resource availability and environmental cues like green-up and snow depth.
• The roles of resource tracking and spatial memory in guiding long-distance migration remain debated, particularly in mammals.

Discussion:

• This study investigated the relative importance of spatial memory versus resource tracking in mule deer migration using movement data.
• Simulations revealed that spatial memory was a stronger driver of migration than resource tracking alone.
• Memory enabled simulated deer to replicate empirical routes and achieve greater foraging benefits.

Key Insights:

• Spatial memory profoundly influences mule deer migration, impacting movement 2-28 times more than resource tracking.
• Migratory routes and seasonal ranges are primarily navigated using spatial memory.
• Resource tracking dictates the timing of beneficial movements within established migratory pathways.

Outlook:

• Understanding the interplay of memory and resource tracking is crucial for conserving migratory mammal populations.
• Future research could explore the neural mechanisms underlying spatial memory in migratory species.
• This work highlights the cognitive abilities essential for successful long-distance animal movements.