Data for: Host plants and landscape predict use of roadside habitat by breeding monarchs

Data for the manuscript "Host plants and landscape predict use of roadside habitat by breeding monarchs." MANUSCRIPT ABSTRACT: Vegetation along roadside edges, while posing some risks, can also provide breeding habitat for monarch butterflies. We investigated how landscape and site-specific factors affect the quality of roadsides as monarch breeding habitat. We surveyed more than 250 sites along roadsides throughout Minnesota for milkweeds, floral resources, and monarch eggs and larvae. We found that milkweed distribution was affected by adjacent land use and geography, with milkweeds more likely to be present in roadsides adjacent to crop and grassland and in the south and west of the state. The presence and density of monarch eggs and larvae was primarily driven by milkweed density, with the likelihood of monarch presence at each site increasing with milkweed density. The density of monarchs per plant increased in sites with lower densities of milkweed, suggesting that monarch eggs are concentrated more densely on fewer plants where milkweed is scarce and spread more thinly across plants where milkweed is common. Monarch density per milkweed increased as sites were farther from core grasslands, to the south, and on narrower roadsides, also suggesting use may be higher in areas with a scarcity of habitat. The density of monarch eggs and larvae were higher in mowed than unmowed milkweed. Our study suggests that roadside habitats effectively provide breeding locations for monarchs, regardless of adjacent land use type and even when distant to high quality natural areas. Our findings assist conservation practitioners in planning and managing roadside habitats for monarchs and other pollinators.

本数据集对应论文《寄主植物与景观格局预测繁殖期帝王蝶对道路沿线生境的利用》。论文摘要：道路沿线边缘的植被虽存在一定潜在风险，但亦可作为帝王蝶（monarch butterfly）的繁殖生境。本研究旨在探究景观与局地因子如何影响道路沿线作为帝王蝶繁殖生境的质量。我们在明尼苏达州全境的道路沿线共设置250余个调查样点，对马利筋（milkweed）、花卉资源以及帝王蝶的卵与幼虫开展了调查。研究发现，马利筋的分布受邻近土地利用类型与地理区位影响，在邻近农田与草地的道路沿线，以及该州南部与西部地区的道路沿线更易出现马利筋。帝王蝶卵与幼虫的存在与否及其种群密度主要由马利筋密度驱动，样点内帝王蝶出现的概率随马利筋密度升高而上升。单株寄主植物上的帝王蝶密度则在马利筋密度较低的样点中更高，这表明当马利筋资源匮乏时，帝王蝶卵会更密集地集中在少量植株上；而当马利筋分布普遍时，卵则会更均匀地分散在更多植株间。随着样点距核心草地越远、地理位置越偏南，以及道路宽度越窄，单株马利筋上的帝王蝶密度会随之升高，这也提示在生境稀缺的区域，帝王蝶对道路生境的利用程度可能更高。被修剪过的道路沿线区域内的马利筋上，帝王蝶卵与幼虫的密度高于未修剪区域。本研究表明，无论邻近土地利用类型如何，即便距离高质量自然生境较远，道路沿线生境均可有效为帝王蝶提供繁殖场所。本研究结果可为生态保护从业者规划与管理面向帝王蝶及其他传粉昆虫的道路沿线生境提供科学参考。