The ecological niche concept describes the set of environmental conditions a species needs to survive and reproduce, but it has traditionally been applied at the species or population level - even though individual animals are known to vary widely in behavior, diet, and habitat choice.

Individuals belonging to the same species do not necessarily use or respond to their environment in the same way. This variation has been traditionally treated as statistical noise but now we know that it has important implications for the long-term survival of a species.

- said Dr. Takola.

Despite this, few tools exist to translate modern tracking data and space use patterns into practical, comparable measures of individual habitat specialisation.

This new workflow, published in the Individual-based Ecology journal, aims to address this gap. Working at the individual level, it treats each animal’s personal range of habitat conditions as its own 'individualised niche', distinguishing for each individual between the conditions it actually uses (its realised niche) and the conditions available to it but not necessarily used (its potential niche). These concepts were defined in a previous study by E. Takola and H. Schielzeth. Takola has now taken these concepts a step further, translating them into a practical workflow for studying individual animals in the wild.

To achieve this, it uses combined mixed-effects resource selection functions such as statistical models that estimate both average habitat preferences and how much individuals deviate from that average with hypervolume exploration methods, a way of mapping all the environmental conditions an individual could occupy as a multidimensional space.

Implemented entirely in R, the workflow draws on tools from ecological niche modeling, behavioral ecology, and spatial ecology. Further, the workflow is divided into three stages: data preparation, analysis, and output generation.

Throughout, it distinguishes between the environmental conditions available to an individual and the conditions it actually uses, allowing researchers to quantify niche breadth or how broad or narrow an individual's habitat use is; niche overlap or how much individuals' habitat use overlaps with one another; and repeatability - how consistent an individual's habitat use is over time.

The lapwing case study puts this into practice. By using publicly available GPS tracking data from 13 northern lapwings, the study shows how the workflow integrates multiple environmental layers such as earthworm abundance, human presence, pesticides, management, soil variables, and vegetation.

Individual organisms differ in genotype, morphology, life strategy, diet, and behavior. Individual-based approaches capture how animals adapt locally and respond to environmental stress in ways population-level averages can obscure.

This has real implications for conservation. Individual-based models, ones that account for energy costs, demographic trends, habitat-selection patterns, and life-history traits, offer a more accurate, mechanistic picture of wild population dynamics, and a better basis for predicting how populations will fare as conditions change.

"Although demonstrated on the northern lapwing, the workflow is designed to be transferable to other mobile species with GPS tracking data, giving ecologists a general-purpose tool for incorporating individual variation into habitat and conservation models."

- explains Takola.

The data and code underpinning the workflow are available on GitHub.

By making individual specialisation measurable and comparable across taxa and datasets, the workflow can help researchers study niche specialization and population-level heterogeneity across ecological scales, linking individual-level variation back to population- and species-level patterns, and giving conservationists a tool to move beyond population averages toward more targeted conservation methods.