Land ownership and use influence grassland bird abundance

Abstract

Populations of grassland songbirds continue to decline, and grasslands devoted to conservation are rare across the Great Plains. To gain the most value from grasslands for grassland birds, we must understand what types of management benefit these species. We evaluated the relative abundance of grassland birds on ownership types and the association of different land use activities with their abundance. We surveyed a wide range of grasslands (e.g., from idle to heavily managed, from remnant prairie to reconstructed) across western Minnesota and northwestern Iowa, USA, in 2013 and 2014. Sites surveyed covered a gradient of landscape context, management history (fire, grazing, reconstruction), and public and private ownership. We evaluated the influence of ownership and management history on the abundance of 12 species of grassland birds by comparing Akaike's Information Criterion values of linear models that included the variables of interest to models that included only local and landscape habitat factors. Ownership explained additional variation in bird abundance beyond local and landscape variables for 7 of the 12 species, and 5 species were more common on private lands. Fire or grazing history explained variation in bird abundance for 11 species, and 7 species had greater abundance on remnant prairie than on reconstructed grassland. For all but 1 species, ownership and management factors significantly improved models above a base model of local and landscape variables typically used to predict abundance. Our results suggest remnant prairie plays an important role for grassland birds, and that grazing could be a tool to increase abundance of some grassland bird species in the region. Furthermore, tracking management history of public lands in a consistent and accessible way could help improve landscape-based models for these species. Ó

Cattle grazing in CRP grasslands during the nesting season: effects on avian abundance and diversity

“…were less dominant relative to rarer species in grazed fields (e.g., eastern meadowlark), resulting in greater species diversity under that disturbance, especially on grazed, unburned fields of eastern Kansas. No other study has assessed the effects of grazing during the primary nesting season in CRP grasslands at a geographic scale in the Great Plains comparable to our study (the research by Ahlering et al 2019 was similar in spatial extent but not exclusively in CRP grasslands or along as steep a longitudinal precipitation gradient as in our study). Variation in responses between more arid western and more mesic eastern Kansas were perhaps due to regional variation in bird species assemblages or long-term effects of climate on soils and plant communities (Borchert 1950, Olff and Ritchie 1998, Díaz et al 2007, despite the relatively short ecological time that CRP fields have been established (≤30 yr).…”

“…This ground-foraging species (Jaster et al 2020) might benefit from more exposed bare ground on grazed fields (Table S1). Others have reported negative effects of grazing on eastern meadowlark abundance (Ahlering et al 2019). Although we acknowledge the potential that detection probability of eastern meadowlarks, and possibly grasshopper sparrows, might have been higher on our grazed fields, meadowlarks are relatively large, vocal, active songbirds in grasslands and were readily detectable among CRP fields.…”

The long shadow of woody encroachment: An integrated approach to modeling grassland songbird habitat

“…While many North American birds have experienced steep declines since 1970, grassland birds are the most imperiled (Rosenberg et al, 2019). They inhabit largely human‐dominated systems, privately owned land, and areas of intensive agriculture (Ahlering et al, 2019; White et al, 2000), and exhibit sharp declines in response to habitat loss, habitat degradation, and habitat fragmentation (Herkert, 1998; Stanton et al, 2018). Compared with most other remaining grassland taxa, such as insects and small mammals, grassland birds often require much larger areas.…”

Assessing GEDI data fusions to map woodpecker distributions and biodiversity hotspots

“…The land ownership of these hotspots is of particular interest in the framework of wildlife management; while wildlife do not respond directly to land ownership, ownership informs habitat management practices (Ahlering et al 2019), which in turn influences the forest structure. For example, in the MWCF ecoregion, old-growth forest is more likely to occur under federal ownership, while clear-cutting is currently more prevalent on lands under private ownership (Phalan et al 2019).…”