Enhanced indicator species performance with increasing contextualization

Abstract

Indicator species need context to perform optimally for conservation purposes. If indicator potential is context‐dependent, then indicators should improve with increasing spatial‐environmental stratification. We tested this hypothesis by hierarchically stratifying a species combinations matrix (plants and wetlands) using regionalization and site typology and analyzing class specificity and occupancy rate for indicators shared across strata. Performance of indicators collectively improved with increased sample stratification providing greater spatial‐environmental context. Carefully considered sample classification schemes could strengthen the value of indicator species for monitoring biodiversity loss, environmental change, and management progress. However, the better accuracy of context‐specific indicators will have to be weighed against the practical need for fewer broad‐based indicators.

Limited Evidence For Indicator Species of High Floristic Quality Wetlands In The US Southern Plains

“…strati cation may reduce compositional variation and strengthen indicator performance (Brooks et al 2006;Bried et al 2019), but effective strati cation may be di cult. In our study area wetlands are hard to geomorphically subclassify (Dvorett et al 2012) and subject to strong climatic gradients and other natural heterogeneity (Hoagland 2000;Gallaway et al 2019), adding to the challenges.…”

“…We calculated site oristic quality using FQI = where , S is number of species, and C is the species conservatism value (integers 0 to 10) obtained from Ewing and Hoagland (2012) We repeated the analysis for wetlands of prairie ecoregions (i.e. all study sites, "prairie wetlands") and for depressional wetlands of the northern Central Great Plains ecoregion ("CGP depressions") in Oklahoma, expecting stronger indicators for CGP depressions due to increased spatial-environmental context (Bried et al 2019). For both contexts we used randomly drawn ~ Main Samples (e.g.…”

Searching for Indicator Species of High Floristic Quality Depressional Wetlands in the US Southern Plains

“…In practice, an indicator's speci city may be viewed as the chance it will correctly identify a target site (positive predictive value) and sensitivity as the chance of nding the indicator ( We repeated the analysis for wetlands of prairie ecoregions (i.e. all study sites, "prairie wetlands") and for depressional wetlands of the northern Central Great Plains ecoregion ("CGP depressions") in Oklahoma, expecting stronger indicators for CGP depressions due to increased spatial-environmental context (Bried et al 2019). For both contexts we used randomly drawn ~ Main Samples (e.g.…”

“…Tools for rapid identi cation of potential reference wetlands are needed, especially when such conditions are rare over large areas containing abundant wetlands. An approach of indicator species, su ciently calibrated (Bried et al 2019), is one option worthy of consideration. Such species may be used for example to rapidly screen wetlands for potential regulatory protection and follow-up intensive assessments in the development permitting process (Stapanian et al 2013).…”

“…Increased ecogeographic and environmental (e.g. hydrogeomorphic) strati cation may reduce compositional variation and strengthen indicator performance(Brooks et al 2006;Bried et al 2019), but effective strati cation may be di cult. In our study area wetlands are hard to geomorphically subclassify(Dvorett et al 2012) and subject to strong climatic gradients and other natural heterogeneity(Hoagland 2000;Gallaway et al 2019), adding to the challenges.…”