Special Feature - Conservation & Management
Using IMBCR Data to Address Management and Conservation Questions
Long-term, rigorous monitoring provides valuable information on population status, allowing managers and biologists to focus limited resources on species of greatest concern. Monitoring populations at local and regional scales also facilitates a mechanistic understanding of how local and regional processes may interact and affect populations (Hewitt et al. 2007, Pavlacky et al. 2017). Here we provide a few examples demonstrating the use of IMBCR data to address specific management or conservation questions using either the annual monitoring effort we conduct each year or targeted monitoring in an overlay project.
Landscape-scale effects of a grassland restoration program
David Pavlacky and coauthors published a study examining the effect of grassland habitat loss on grassland bird diversity across the western Great Plains, and if and how lands enrolled in the Conservation Reserve Program (CRP) offset this loss. They used the “background” IMBCR data from surveys conducted each year to evaluate hypotheses for the effects of habitat loss and restoration on grassland birds. They found that occupancy and species richness of grassland specialists declined with a loss of grassland habitat, but increased with greater CRP in the surrounding landscape. In addition, although species richness of grassland specialists was similar between intact grasslands and landscapes containing CRP, turnover in species composition between the two landscapes suggested that landscapes with CRP lacked complete representation of grassland specialists. Lastly, the predicted effect of adding 1 km2 of CRP to the landscape increased the richness of grassland specialists the most in northern latitudes, like northeastern Montana. Access the full text publication via ResearchGate here.
Sagebrush birds experience declining population trends with heavy natural gas energy development
In a targeted overlay project, Bird Conservancy monitored birds over a 10-year period in the Atlantic Rim Natural Gas Field (south-central Wyoming) to determine energy development impacts on sagebrush birds of concern. We surveyed birds in a high and low-development stratum within the project area, and also on surrounding land as part of the “background” IMBCR effort, which served as a reference sample. We then estimated population trends in occupancy and species richness relevant to a priori management triggers set by the BLM. Twenty-four species had negative trends in the high-development stratum, including Sage Thrasher, which had a large enough decline to meet a management trigger. Overall species richness also showed a negative trend in the high-development stratum relative to the background and low-development strata, and well pad density was the leading causal factor for observed negative impacts. Read the full publication here.
Predicting the effects of pinyon-juniper removal on birds associated with pinyon-juniper and sagebrush habitats
Nick Van Lanen and co-authors used “background” IMBCR data across several western Bird Conservation Regions (BCR) to model population trends and density-habitat relationships for sagebrush-associated, pinyon-juniper (PJ)-associated, and generalist songbird species. They found eight decreasing and 14 increasing regional populations, and in particular, no species were found to be declining within the highest elevation-portion of the study area (the Northern Rockies BCR). Their models also indicated that PJ removal efforts would benefit Sage Thrasher, Brewer’s Sparrow, and Green-tailed Towhee populations, but harm PJ-associated species, like Bewick’s Wren and Gray Flycatcher. Their results, including predicted density maps, can help prioritize species and regions for conservation action and inform management for species with disparate habitat needs. Read the open-access article here.