D3125: Does milkweed species influence monarch survival? Maximizing conservation efforts of the monarch butterfly in the face of predators

In species of conservation concern, maximizing the efficacy of conservation efforts is crucial for success. The decline of the monarch butterfly has been met with a desire from the public for involved conservation action. However, the approach to conservation is complex as the decline of this migratory species is multi-factorial. Established efforts have primarily focused on mitigating the loss of milkweed hostplants from the summer breeding landscape lost due to agricultural development. There are dozens of species that are native to North America and conservation plantings often include several species which differ in important plant traits like trichome density, defensive chemistry, and physical structure. Therefore, this conservation effort could be complicated by the inherent differences between milkweed species, and what communities of arthropod predators they harbor. Monarchs face a steep population bottleneck in the first days of their life, in which less than 5% make it beyond their eighth day of life, largely due to predation (Prysby 2004, de Alma 2004). The aim of this work is to quantify interacting arthropod communities, particularly monarchs, ants and aphids, on the three most commonly planted milkweed species in the Northeastern USA. These findings are paired with behavioral trials quantifying the impact ants have on monarch larval performance, as well as findings from a state-wide survey to gardeners assessing what species of milkweed they prefer to plant. These findings will inform and maximize conservation efforts of monarchs in the face of invertebrate predators in a way relevant to gardeners implementing these practices.