TY - JOUR

T1 - Application of modern coexistence theory to rare plant restoration provides early indication of restoration trajectories

AU - Aoyama, Lina

AU - Shoemaker, Lauren G.

AU - Gilbert, Benjamin

AU - Collinge, Sharon K.

AU - Faist, Akasha M.

AU - Shackelford, Nancy

AU - Temperton, Vicky M.

AU - Barabás, György

AU - Larios, Loralee

AU - Ladouceur, Emma

AU - Godoy, Oscar

AU - Bowler, Catherine

AU - Hallett, Lauren M.

N1 - This paper is a joint effort of the sToration working group hosted by sDiv, the Synthesis Centre of the German Centre for Biodiversity Research (iDiv) Helle-Jena-Leipzig (FZT 118, 02548816). Vernal pool data collection was funded by the Air Force Center for Environmental Excellence, the US Fish and Wildlife Service, CH2M Hill, and NSF LTREB grants (DEB-0744520 and DEB-1257385). Lina Aoyama was supported by a USDA NIFA Predoctoral Fellowship (2021-67034-35111). György Barabás was supported by the Swedish Research Council (Vetenskapsrådet), grant 2017-05245. Oscar Godoy was supported by the Spanish Ministry of Economy and Competitiveness (MINECO) and by the European Social Fund through the Ramón y Cajal Program (RYC-2017-23666). Sharon K. Collinge designed the experiment and Sharon K. Collinge and Akasha M. Faist collected data. Lina Aoyama developed and implemented the statistical approach with input from Lauren G. Shoemaker, Benjamin Gilbert, and Lauren M. Hallett. Lina Aoyama, Lauren G. Shoemaker, Lauren M. Hallett, BG, Sharon K. Collinge, Akasha M. Faist, Nancy Shackelford, and Vicky M. Temperton wrote the first draft and all authors contributed to manuscript edits. Publisher Copyright: © 2022 The Authors. Ecological Applications published by Wiley Periodicals LLC on behalf of The Ecological Society of America.

PY - 2022/10/1

Y1 - 2022/10/1

N2 - Restoration ecology commonly seeks to re-establish species of interest in degraded habitats. Despite a rich understanding of how succession influences re-establishment, there are several outstanding questions that remain unaddressed: are short-term abundances sufficient to determine long-term re-establishment success, and what factors contribute to unpredictable restorations outcomes? In other words, when restoration fails, is it because the restored habitat is substandard, because of strong competition with invasive species, or alternatively due to changing environmental conditions that would equally impact established populations? Here, we re-purpose tools developed from modern coexistence theory to address these questions, and apply them to an effort to restore the endangered Contra Costa goldfields (Lasthenia conjugens) in constructed (“restored”) California vernal pools. Using 16 years of data, we construct a population model of L. conjugens, a species of conservation concern due primarily to habitat loss and invasion of exotic grasses. We show that initial, short-term appearances of restoration success from population abundances is misleading, as year-to-year fluctuations cause long-term population growth rates to fall below zero. The failure of constructed pools is driven by lower maximum growth rates compared with reference (“natural”) pools, coupled with a stronger negative sensitivity to annual fluctuations in abiotic conditions that yield decreased maximum growth rates. Nonetheless, our modeling shows that fluctuations in competition (mainly with exotic grasses) benefit L. conjugens through periods of competitive release, especially in constructed pools of intermediate pool depth. We therefore show how reductions in invasives and seed addition in pools of particular depths could change the outcome of restoration for L. conjugens. By applying a largely theoretical framework to the urgent goal of ecological restoration, our study provides a blueprint for predicting restoration success, and identifies future actions to reverse species loss.

AB - Restoration ecology commonly seeks to re-establish species of interest in degraded habitats. Despite a rich understanding of how succession influences re-establishment, there are several outstanding questions that remain unaddressed: are short-term abundances sufficient to determine long-term re-establishment success, and what factors contribute to unpredictable restorations outcomes? In other words, when restoration fails, is it because the restored habitat is substandard, because of strong competition with invasive species, or alternatively due to changing environmental conditions that would equally impact established populations? Here, we re-purpose tools developed from modern coexistence theory to address these questions, and apply them to an effort to restore the endangered Contra Costa goldfields (Lasthenia conjugens) in constructed (“restored”) California vernal pools. Using 16 years of data, we construct a population model of L. conjugens, a species of conservation concern due primarily to habitat loss and invasion of exotic grasses. We show that initial, short-term appearances of restoration success from population abundances is misleading, as year-to-year fluctuations cause long-term population growth rates to fall below zero. The failure of constructed pools is driven by lower maximum growth rates compared with reference (“natural”) pools, coupled with a stronger negative sensitivity to annual fluctuations in abiotic conditions that yield decreased maximum growth rates. Nonetheless, our modeling shows that fluctuations in competition (mainly with exotic grasses) benefit L. conjugens through periods of competitive release, especially in constructed pools of intermediate pool depth. We therefore show how reductions in invasives and seed addition in pools of particular depths could change the outcome of restoration for L. conjugens. By applying a largely theoretical framework to the urgent goal of ecological restoration, our study provides a blueprint for predicting restoration success, and identifies future actions to reverse species loss.

KW - Lasthenia

KW - modern coexistence theory

KW - population dynamics

KW - relative nonlinearity

KW - restoration

KW - storage effect

KW - vernal pools

KW - Ecosystems Research

UR - http://www.scopus.com/inward/record.url?scp=85133416140&partnerID=8YFLogxK

UR - https://www.mendeley.com/catalogue/b2645465-f4bf-3883-bca8-b7d56b121acb/

U2 - 10.1002/eap.2649

DO - 10.1002/eap.2649

M3 - Journal articles

C2 - 35560687

AN - SCOPUS:85133416140

VL - 32

JO - Ecological Applications

JF - Ecological Applications

SN - 1051-0761

IS - 7

M1 - e2649

ER -