A Landscape-Level Assessment of Restoration Resource Allocation for the Eastern Monarch Butterfly

The Monarch butterfly eastern population ( Danaus plexippus ) is in decline primarily due to habitat loss. Current restoration programs focus on re-establishing milkweed, the primary food resource for caterpillars, central United States of America. However, individual components life cycle function as part an integrated whole. Here we develop MOBU-SDyM, a migration-wide systems dynamics model migratory explore alternative management strategies’ impacts. Our offers several advances over previous efforts, considering complex variables such dynamic temperature-dependent developmental times, availability, and weather-related mortality across entire range. We first explored whether predominant milkweed mid-range Monarch’s migration could be overestimating actual requirements. Second, examined robustness using recommended 1.2–1.6 billion stems policy objective when accounting factors droughts, changes temperature, stems’ effective usability by Monarchs. Third, used estimate number distribution northern, central, southern regions breeding range needed reach self-sustainable long-term six overwintering hectares. analysis revealed that concentrating growth region increases size colonies more so than equivalent south region, with northern having negligible effect. even though simulating increase did not play key role increasing colonies, it plays paramount keeping above critically small size. Abiotic considerably influenced needed, but, general, our estimates required were 43–91% larger currently set target: optimal allocation efforts 7.35, 92, 0.15% south, regions, respectively. Systems dynamics’ analytical computational strengths provided us new avenues investigate biological system contribute robust policies this unique species.