Prey encounters and spatial memory influence use of foraging patches in a marine central place forager

Virginia Iorio* (Corresponding Author), Isla Graham, Rebecca Hewitt, Geert Aarts, Enrico Pirotta, Gordon D. Hastie, Paul Thompson

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

7 Citations (Scopus)
15 Downloads (Pure)


Given the patchiness and long-term predictability of marine resources, memory of high-quality foraging grounds is expected to provide fitness advantages for central place foragers. However, it remains challenging to characterise how marine predators integrate memory with recent prey encounters to adjust fine-scale movement and use of foraging patches. Here, we used two months
of movement data from harbour seals (Phoca vitulina) to quantify the repeatability in foraging patches as a proxy for memory. We then integrated these data into analyses of fine-scale movement and underwater behaviour to test how both spatial memory and prey encounter rates influenced the seals’ Area Restricted Search (ARS) behaviour. Specifically, we used one month’s GPS data from 29 individuals to build spatial memory maps of searched areas, and archived accelerometery data from a subset of five individuals to detect prey catch attempts, a proxy for prey encounters.
Individuals were highly consistent in the areas they visited over two consecutive month. Hidden Markov Models showed that both spatial memory and prey encounters increased the probability of seals initiating ARS. These results provide evidence that predators use memory to adjust their fine scale movement and this ability should be accounted for in movement models.
Original languageEnglish
Article number20212261
Number of pages10
JournalProceedings of the Royal Society B: Biological Sciences
Issue number1970
Early online date2 Mar 2022
Publication statusPublished - 9 Mar 2022

Bibliographical note

We would like to thank all the staff and students who have been involved in the data collection. Matt Carter for his support in the early stages of the analysis, Sophie Brasseur for her valuable input and ideas on harbour seal feeding strategies and Thomas Bodey who provided suggestions and comments on the manuscript draft. We dedicate this study to Dr Bernie McConnell, who did so much to drive the development of the telemetry devices that revealed these and many other insights into the behaviour of seals at sea.

Data Availability Statement

The data are deposited on BirdLife International's Seabird Tracking Database


  • ARS
  • Spatial memory
  • Hidden Markov model
  • accelerometer
  • harbour seals
  • repeatability


Dive into the research topics of 'Prey encounters and spatial memory influence use of foraging patches in a marine central place forager'. Together they form a unique fingerprint.

Cite this