Islands: Microcosms of socioecological change and barometers of global biodiversity trends
Islands host exceptional biodiversity yet account for most human‑driven extinctions. Centered on the extinction of the Christmas Island shrew, this study explores how invasive species, climate change, and governance gaps drive island biodiversity loss, while highlighting new interdisciplinary and community‑based approaches shaping island conservation.
Subject Tags
- Conservation Planning
- Ecosystem management
- Biodiversity
Summary
The extinction of the Christmas Island shrew underscores the extraordinary vulnerability of island species and the growing role of islands as global extinction hotspots. Restricted to a single island, this species declined rapidly following the introduction of invasive mammals, novel diseases, habitat disturbance, and other human‑driven pressures. Its loss reflects a broader pattern of biodiversity erosion on islands, which cover a small fraction of Earth’s land area yet support a disproportionate share of global biodiversity and account for most recent human‑caused extinctions. Islands are also culturally rich socioecological systems, shaped by deep local ecological knowledge and long histories of human–environment relationships. Today, these systems face accelerating change driven by interacting threats including invasive species, habitat loss, pollution, climate change, and governance challenges. While islands have been central to some of conservation’s greatest successes, major knowledge gaps remain—particularly for poorly studied species, long‑term monitoring, freshwater ecosystems, and the integration of ecological and sociocultural data. This special issue highlights recent advances, emerging tools, and interdisciplinary approaches that address these gaps, showcasing islands not only as vulnerable systems but also as powerful models for understanding and responding to global biodiversity change.
Citation
Rocha, R., Russell, J. C., Holmes, N. D., Dias, M. P., Chaigneau, T., & Nuno, A. (2026). Islands: Microcosms of socioecological change and barometers of global biodiversity trends. Conservation Science and Practice, 8(3).
TNC Authors
-
Nick D. Holmes
Associate Director, Oceans Program. California
The Nature Conservancy
Email: nick.holmes@tnc.org