Population Dynamics and Trophic Interactions in Arctic Ecosystems

The Arctic comprises a mosaic of tundra, ice‐associated habitats and fragmented wetlands, supporting simplified yet highly dynamic food webs. Small mammals such as lemmings and voles exhibit pronounced population cycles, driven by the interplay between plant productivity, predator pressure and climatic variability. Top‐down forces—principally predation by foxes, raptors and mustelids—interact with bottom‐up constraints, notably seasonal pulses in vegetation growth and nutrient availability. Keystone predators further engineer habitats through denning activities, altering soil nutrients and promoting localized vegetation hotspots. Changing snow cover, permafrost thaw and altered seed‐crop frequencies are shifting the timing and amplitude of these cycles, with cascading effects on avian breeders, herbivore survival and carbon flux. Understanding these interlinked processes is critical for forecasting biodiversity responses, managing conservation priorities and informing global models of ecosystem resilience under rapid Arctic warming.

Research from Nature Portfolio

Studies have revealed that Arctic fox denning acts as a focal point for nutrient enrichment in the tundra. Soils on occupied dens contain substantially higher inorganic nitrogen and extractable phosphorus than adjacent areas, persisting beyond a single season. Enhanced soil fertility drives a two‐ to threefold increase in local plant biomass, creating resource patches that attract herbivores and may modify grazing patterns. These nutrient hotspots thus exemplify how top predators function as ecosystem engineers, mediating plant–herbivore interactions and contributing to spatial heterogeneity in population dynamics.

Population Dynamics and Trophic Interactions in Arctic Ecosystems publication trend

The graph below shows the total number of articles in population dynamics and trophic interactions in arctic ecosystems across all publications each year (not limited to Nature Index journals).

Technical terms

Population cycle: Regular, multi‐year fluctuations in the abundance of a species driven by interacting biotic and abiotic factors.

Trophic interaction: Feeding relationships between organisms, including herbivory, predation and competition, that structure food webs.

Ecosystem engineer: A species that modifies, creates or maintains habitat and resource availability for other organisms through its activities.

Resource pulse: A sudden and temporary increase in resource availability (e.g. mast seeding) that can trigger consumer and predator population responses.

Intraguild competition: Competitive interactions between species that share similar trophic roles, potentially including predation on one another.

References

1. Small rodent population cycles and plants – after 70 years, where do we go?. Biological Reviews (2023).
2. Coexistence of two sympatric predators in a transitional ecosystem under constraining environmental conditions: a perspective from space and habitat use. Movement Ecology (2023).
3. Population cycles and outbreaks of small rodents: ten essential questions we still need to solve. Oecologia (2020).
4. Arctic foxes as ecosystem engineers: increased soil nutrients lead to increased plant productivity on fox dens. Scientific Reports (2016).