Win-stay/lose-switch, prospecting-based settlement strategy may not be adaptive under rapid environmental change

Janusz Kloskowski

doi:10.1038/s41598-020-79942-3

Abstract

Understanding animal responses to environmental change is crucial for management of ecological traps. Between-year habitat selection was investigated in red‐necked grebes (Podiceps grisegena) breeding on semi-natural fish ponds, where differential stocking of fish created contrasting yet poorly predictable brood-stage food availabilities. Grebes lured to low-quality ponds were more likely to shift territories than birds nesting on high-quality ponds, and tended to move to ponds whose habitat quality had been high in the previous year, irrespective of the current quality of the new and old territories. The territory switchers typically visited their future breeding ponds during or immediately after the brood-rearing period. However, owing to rotation of fish stocks, the habitat quality of many ponds changed in the following year, and then switchers from low-quality ponds and stayers on previously high-quality ponds were ecologically trapped. Thus, although breeders were making an informed choice, their settlement decisions, based on the win–stay/lose–switch rule and prospecting a year in advance, were inappropriate in conditions of year-to-year habitat fluctuations. Effective adaptation to rapid environmental change may necessitate both learning to correctly evaluate uncertain environmental cues and abandonment of previously adaptive decision-making algorithms (here prioritizing past-year information and assuming temporal autocorrelation of habitat quality).

Highlights

Understanding animal responses to environmental change is crucial for management of ecological traps
Inattention to or misinterpretation of cues on habitat quality associated with human-induced rapid environmental change (HIREC) may result in ecological traps that drive populations toward decline[4,5,6]
Increasing attention has recently been paid to means of behavioural readjustment as an escape from ecological traps associated with HIREC, either via natural selection of genetically determined traits or via learning[8,9,10]

Summary

Introduction

Understanding animal responses to environmental change is crucial for management of ecological traps. Decision rules adopted for between-year habitat selection were investigated in red-necked grebes (Podiceps grisegena) nesting on fish ponds, where food resources for breeding birds were determined by the density and size structure of the stocked fish. Differential fish stocking created a clear dichotomy in habitat quality among well-defined habitat patches; the suboptimal habitat provided alluring cues, while the habitat quality of individual patches (ponds) alternated irregularly (even from year to year, i.e. faster than habitat shifts that would have occurred in natural settings) Owing to their long lifespan[28], grebes should have the potential to learn from past experience about the real value of novel habitats. I predicted that quick alternation of fish stocks disrupting temporal covariation of habitat quality in ponds would render grebes’ settlement decisions vulnerable to bias

Methods

Results

Conclusion