Ecological Discord and the Importance of Scale in Scientific Inquiry

Abstract

Scale is widely recognized today as an important concept in ecology because the scale of investigation determines the patterns and processes that can be observed. Ecological investigations can produce different outcomes depending on the scale at which observations are made, and ecological disagreements have occurred simply because investigators addressed the same question using different scales. Here I draw on quail research to illustrate the importance of scale in ecological studies and how lack of scale consideration can lead to discord. I use northern bobwhite (Colinus virginianus) as the focal species and discuss 2 areas of investigation (woody-cover requirements and influence of rainfall) that are characterized by confusion and disagreement but where consideration of scale brings clarity. In the process, I discover 2 formerly unrecognized patterns: northern bobwhite use of woody cover is inversely related with spatial extent of observation, and the influence of rainfall on northern bobwhite abundance decreases with decreasing spatial extent. In both cases, consideration of scale clarifies muddled knowledge and creates a unified framework for management. Future ecological investigations should formulate research questions within a scale framework, provide an explicit statement of scale in methods, and interpret findings within a scale context to help advance wildlife science and management.

Temporal and scalar variations affect resource use of northern bobwhite broods

“…There is an increasing recognition that resource use occurs in flux with phenology of exploited biotic resources, physiological development of the exploiting species, abiotic conditions, and many other spatially and temporally variable factors (Rettie & Messier, 2000; Sinnott et al., 2021; Tsalyuk et al., 2019; Van der Merwe & Marshal, 2012). Studies without context of temporal and spatial scales may give rise to vastly opposing interpretations of resource use (Hernández, 2020; Hobbs, 2003). Accordingly, the processes of selection for a given species require research across multiple scales and regions to describe disparate behavior under varying conditions which in turn governs locally relevant management practices (Kauffman et al., 2009).…”

Quail and rain in semiarid rangelands: Does management matter?

“…That is, rainfall may be exerting a strong influence on regional abundance—elevating or depressing abundance at broad spatial extents—while local abundance may vary spatially within these general bounds as local factors (of which rainfall is 1) change across space. Such a proposed hierarchical framework for understanding the influence of rainfall on bobwhite populations in semiarid environments (Hernández 2020) is similar to that proposed for other systems, whereby coarse‐grain patterns constrain fine‐scale processes, but variability at the fine scale is influenced by factors operating at this fine scale plus those operating at the coarse scale (Sala et al 1988, Fuhlendorf et al 2017).…”

“…We observed that rainfall at the site level explained considerably less (<10%) of the variation in bobwhite density than past studies have documented for rainfall at a regional level. Recently, Hernández (2020) suggested that the influence of rainfall on bobwhite abundance may decrease with decreasing spatial extent based on hierarchy theory (Allen and Star 1982). Hierarchy theory proposes that systems are structured in nested levels that result in a constraint envelope, whereby the dynamics of an ecological system operate within the limitations imposed by the environmental limits of higher levels and the biotic potential of lower levels (O'Neill et al 1989, Wu 2013).…”

“…Such profound influence of rainfall may suggest that quail management in semiarid rangelands is a futile endeavor. However, the influence of rainfall on quail populations may vary by scale, with rainfall possibly exerting a greater influence on quail populations at large spatial extents (e.g., ≥4 million ha) but a lesser influence at smaller spatial extents (e.g., 2,000 ha; Hernández 2020). If rainfall is less influential at smaller scales, then other variables such as those that can be influenced by management (e.g., brush cover, grass height) may assume greater importance (Hernández 2020).…”

A Call for More Nuanced Dialogues About Trophy Hunting

“…Levin (1992), and most recently Hernandez (2020), have noted that space, time, community structure, and function are critically important to understanding ecological processes. Coupled with biological diversity, those elements necessitate that investigators explicitly state the temporal and spatial scales that were operative during their research.…”