Integrated vegetation management within electrical transmission landscapes promotes floral resource and flower-visiting insect diversity.

Electrical transmission rights-of-way are ubiquitous and critical infrastructure across the landscape. Active vegetation management of these rights-of-way, a necessity to deliver electricity more safely, maintains these landscape features as stages of early successional habitat, a rarity in many regions, making these areas viable movement corridors for many taxa. The goals of this study were to (i) evaluate the effects of different electrical transmission landscape management practices on flowering plant and flower-visiting insect diversity parameters and (ii) generate conservation management inferences for these landscapes. In this study we tested the impact of three vegetation management levels across 18 electrical transmission sites. We evaluated the effects of treatment on bloom abundance and species richness as well as flower-visiting insect abundance and family richness. We identified 76541 flowers/inflorescences across 456 transects, including 188 species in 56 plant families. Additionally, we obtained data on 11361 flower-visitoring insects representing 33 families from 2376 pan trap sets. High vegetation management favored the reduction of coarse woody debris in the sites and harbored the highest level of abundance and richness of both floral resources and flower-visiting insects. We discuss that we can align social and ecological values of rights-of-way, ensuring their sustainability by applying regular and targeted integrated vegetation management. Thus, we can use rights-of-way landscapes not only as an effective management strategy for the delivery of essential human services, but also to provide conservation benefits for wild pollinators.

Better Understanding the Potential Importance of Florida Roadside Breeding Habitat for the Monarch.

The North American monarch butterfly (Danaus plexippus) population has declined significantly over the past two decades. Among the many other factors, loss of breeding habitat has been implicated as a potential leading driver. In response, wildlife agencies and conservation practitioners have made a strong push to restore and conserve milkweeds on both wild and managed landscapes including agricultural lands as well as transportation and utility rights-of-way. Roadsides in particular have been emphasized as a targeted landscape for monarch habitat restoration. While much attention has been focused on habitat in California, along the I-35 corridor from Texas to Minnesota, and more broadly across the agricultural Midwest, research on the occurrence of roadside breeding habitat and the development of best vegetative management practices conducted in the Deep South has been limited. We sampled roadside verges in north-central Florida for the presence of two early season milkweed species, that are particularly important for early season monarch recolonization, Asclepias tuberosa and Asclepias humistrata. Our findings suggest that roadsides harbor extensive populations of the target milkweeds with the vast majority of plants occurring on the back slope of the verge. Alterations to current roadside mowing frequency and scope are needed to effectively conserve these populations and ensure that they are available for use by the monarch.