Habitat restoration opportunities, climatic niche contraction, and conservation biogeography in California's San Joaquin Desert

Abstract

A recent global trend toward retirement of farmland presents opportunities to reclaim habitat for threatened and endangered species. We examine habitat restoration opportunities in one of the world's most converted landscapes, California's San Joaquin Desert (SJD). Despite the presence of 35 threatened and endangered species, agricultural expansion continues to drive habitat loss in the SJD, even as marginal farmland is retired. Over the next decades a combination of factors, including salinization, climate change, and historical groundwater overdraft, are projected to lead to the retirement of more than 2,000 km 2 of farmland in the SJD. To promote strategic habitat protection and restoration, we conducted a quantitative assessment of habitat loss and fragmentation, habitat suitability, climatic niche stability, climate change impacts, habitat protection, and reintroduction opportunities for an umbrella species of the SJD, the endangered blunt-nosed leopard lizard (Gambelia sila). We use our suitability models, in conjunction with modern and historical land use maps, to estimate the historical and modern rate of habitat loss to development. The estimated amount of habitat lost since the species became protected under endangered species law in 1967 is greater than the total amount of habitat currently protected through public ownership and conservation easement. We document climatic niche contraction and associated range contraction away from the more mesic margins of the species' historical distribution, driven by the anthropogenic introduction of exotic grasses and forbs. The impact of exotic species on G. sila range dynamics appears to be still unfolding. Finally, we use NASA fallowed area maps to identify 610 km 2 of fallowed or retired agricultural land with high potential to again serve as habitat. We discuss conservation strategies in light of the potential for habitat restoration and multiple drivers of ongoing and historical habitat loss.

Trends in the Massachusetts cranberry industry create opportunities for the restoration of cultivated riparian wetlands

“…The retirement of farmland now occurring in many high‐income and urbanizing nations presents potential opportunities for ecological restoration (Whitney ; Comin et al ; Lee et al ; Moreira & Russo ; Chazdon ; Queiroz et al ). The forces that influence farmland retirement and the potential fate of retired farmland differ widely based on economic and geographic contexts (Poore ; Stewart et al ), yet these trends can be used to develop specific restoration programs. Conservation and restoration practitioners can observe trends in land‐use change using remote sensing in order to identify and prioritize sites for land protection (Moreira & Russo ; Gimmi et al ), particularly sites with the potential to offer valuable ecosystem services and that may otherwise be developed for industrial, commercial, or residential use.…”