Dynamical facilitation of the ideal free distribution in nonideal populations

• Published in: Ecology and evolution Vol. 8; no. 5; pp. 2471 - 2481
• Main Authors: Street, Garrett M., Erovenko, Igor V., Rowell, Jonathan T.
• Format: Journal Article
• Language: English
• Published: England John Wiley & Sons, Inc 01.03.2018; John Wiley and Sons Inc
• Subjects: Breeding; cognition; Colonization; Dispersal; Dispersion; facilitation; fitness; modeling; movement; Original Research; Perception; Population growth; reproduction; simulation; Spatial discrimination; modeling; cognition; fitness; simulation; dispersal; facilitation; movement; perception; reproduction
• ISSN: 2045-7758; 2045-7758
• DOI: 10.1002/ece3.3811

The ideal free distribution (IFD) requires that individuals can accurately perceive density‐dependent habitat quality, while failure to discern quality differences below a given perception threshold results in distributions approaching spatial uniformity. Here, we investigate the role of population growth in restoring a nonideal population to the IFD. We place a simple model of discrete patch choice under limits to the resolution by which patch quality is perceived and include population growth driven by that underlying quality. Our model follows the population's distribution through both breeding and dispersal seasons when perception limits differ in their likely influence. We demonstrate that populations of perception limited movers can approximate an IFD provided sufficient population growth; however, the emergent IFD would be temporally inconstant and correspond to reproductive events. The time to emergence of the IFD during breeding is shorter under exponential growth than under logistic growth. The IFD during early colonization of a community persists longer when more patches are available to individuals. As the population matures and dispersal becomes increasingly random, there is an oscillation in the observance of IFD, with peaks most closely approximating the IFD occurring immediately after reproductive events, and higher reproductive rates producing distributions closer to the IFD. The Ideal Free Distribution (IFD) is the theoretical underpinning of numerous ecological models, yet multiple conditions can contribute to deviation from IFD. We show that inclusion of population dynamics can overcome non‐ideal behavior to promote the emergence of IFD. We discuss how these findings influence numerous ecological processes and our use of distribution models, and provide suggestions on how to improve detection and study of IFD.