Managing the middle: A shift in conservation priorities based on the global human modification gradient

Abstract

An increasing number of international initiatives aim to reconcile development with conservation. Crucial to successful implementation of these initiatives is a comprehensive understanding of the current ecological condition of landscapes and their spatial distributions. Here, we provide a cumulative measure of human modification of terrestrial lands based on modeling the physical extents of 13 anthropogenic stressors and their estimated impacts using spatially explicit global datasets with a median year of 2016. We quantified the degree of land modification and the amount and spatial configuration of low modified lands (i.e., natural areas relatively free from human alteration) across all ecoregions and biomes. We identified that fewer unmodified lands remain than previously reported and that most of the world is in a state of intermediate modification, with 52% of ecoregions classified as moderately modified. Given that these moderately modified ecoregions fall within critical land use thresholds, we propose that they warrant elevated attention and require proactive spatial planning to maintain biodiversity and ecosystem function before important environmental values are lost.

City sicker? A meta‐analysis of wildlife health and urbanization

“…Furthermore, we recognize the potential for spatial error and change over time when using point locations to estimate local human footprint from a global dataset (Kennedy et al . ). When we accounted for the degree of urban development, we found that habitats with greater urban development were associated with lower parasitism (with all transmission modes combined due to smaller sample size), suggesting that the transmission of some types of parasites may be interrupted in highly urban areas.…”

Impacts of oil and gas development on duck brood abundance

“…We calculated footprints as the proportion of a buffer circle around a wetland centroid covered by each feature using binary rasters of disturbance features (1 or 0) summarized using the NACT toolbox in ArcMap 10.4 (Price et al ). This approach supported principles of parsimony and provided a realistic metric of disturbance where values ranged from zero (no disturbance within the buffer circle) to 1 (the buffer circle consists entirely of disturbance features; Kennedy et al ).…”

“…We assumed a certain level of non‐independence between our 3 selected disturbance features and addressed any resulting potential bias using a fuzzy algebraic sum, which is a fuzzy operator common to geospatial analyses (Bonham‐Carter , Malczewski , Theobald , Kennedy et al ). The sum and disturbance index can be described as: where H it is the disturbance index for wetland i during year t and F wit , F rit , and F mit are the footprint values for a well, road, and gravel pit, respectively, at wetland i during year t .…”

Finding middle ground: Extending conservation beyond wilderness areas

“…Venter, Possingham, and Watson (2019) express two main concerns with Kennedy et al (2019): (a) that the results "underestimate the extent, and therefore importance, of Earth's remaining unmodified lands"; and that (b) "the HM exhibits high rates of error." Venter, Possingham, and Watson (2019) express two main concerns with Kennedy et al (2019): (a) that the results "underestimate the extent, and therefore importance, of Earth's remaining unmodified lands"; and that (b) "the HM exhibits high rates of error."…”

“…In fact, in Kennedy et al (2019), we call for "a focus on preventing and confining habitat loss" in the remaining one-third of the world's low modified ecoregions. Importantly, we also call for increased attention to the 52% of moderately modified ecoregions, which fall through the cracks under current conservation prioritization schemes.…”