Evaluating the benefitsof higher diversity CRP plantings for at-rsik speceis
April 2011 - December 2013
Land enrolled in the USDA Conservation Reserve Program (CRP) covers more than a million acres in Nebraska. However, little attention has been given to the potential of CRP as a resource in the conservation of at-risk species. For policy and planning purposes, it is important to quantify the species composition of CRP plantings and the relative impacts of different grass and forb planting mixes on local diversity. For example, several designated at-risk butterfly species require specific plant species for successful reproduction. Additionally, forbs are needed as nectar sources for most adult species of butterflies. Landowners are not currently required to include any specific species in their CRP seeding mix, and forb diversity plantings vary. The project objective is to evaluate potential habitat benefits of a variety of CRP planting mixes for at-risk species, including birds, butterflies, bees and fish. During the summer 2013 field season, a large portion of time was spent setting up control plots and sampling areas, installing pitfall traps, learning auditory and visual cues to identify birds, and learning local vegetation. Two technicians assisted with all activities. The following tasks have been completed on the Smith's CRP site in Holt County, NE: 1. Ground dwelling invertebrate sampling: Pitfall trapping to sample ground dwelling insects palatable to upland bird chicks cross the control (standard CRP seed mix plantings) and pollinator (high forb, high diversity CRP seed mix plantings) plots. Three samplings occurred thus far: one in early June, one in early July and one in late July/Early August. 2. Pollinator sampling: Blue Vane traps were set up to sample pollinator assemblages across the control and pollinator plots in the site. This will provide us with baseline data to compare with future years, once the pollinator plots are established. Sampling occurred during summer 2013. Additionally, sweep net sampling (to capture, record and release butterfly species) occurred in late summer 2013. 3. Bird sampling: Point count surveys were conducted across the pollinator and control plots to establish both baseline habitat usage and a running list of bird species that visit and inhabit the entire site. Five point counts were conducted between mid-June and mid-July. The first sampling was delayed until mid-June due to the time required to learn bird calls, and to train the technicians. 4. Vegetation surveys: Vegetation surveys are continuously conducted across the pollinator and control plots using a cover/frequency protocol to track changes in diversity and grass to forb ratios. A total of 15 square meters is measured within every of the larger 18 control and pollinator plots. 5. Mapping: Extensive GPS survey of the field is continuous and will provide us with the ability to revisit sampling areas in future field seasons and the capacity to create user-friendly ways of disseminating our data to broad audiences.