Coda
National and international policies have embraced the principle of conserving 30% of land and water by 2030. To protect biodiversity, this so-called ‘30×30’ must be achieved in each ecoregion, through conservation of the large habitat areas that resemble wilderness, combined with protection and restoration of many small habitat patches in ecoregions severely affected by human activities. In fact, in highly human-modified regions, reaching area targets will be possible only through protection of small patches and habitat restoration. In such regions, conservation and restoration of many small areas is essential to get to 30×30, and such areas may represent the greatest net gains for area-based habitat conservation going forward.
More broadly, realizing 30×30 and other ambitious, collective, area-based plans will be possible only through coordination (Eckertet al. 2023) and if we promptly recognize common ground among researchers working on biodiversity conservation. Ongoing disagreements such as the fragmentation debate are secondary to the general principles we outline in this letter, and we are confident that they will be resolved as data accumulate and science progresses. In the meantime, to address a global biodiversity emergency, proactive implementation of shared principles will bolster our chances of preserving the Earth’s biodiversity heritage.
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