Cumulative impacts of roads and energy infrastructure on grassland songbirds

Abstract

Comparing impacts of co-occurring anthropogenic features is necessary for regional planning and can help identify mechanisms of negative impacts of development on wildlife. Because of the vast abundance of anthropogenic features in the Northern Great Plains, their combined negative impacts on songbird habitat use (e.g., abundance) and productivity (e.g., nesting success and clutch size) could exacerbate the decline of songbird populations. We compared the cumulative effects of energy-related infrastructure (oil wells, shallow gas wells, and roads) on habitat use and productivity of songbirds across a 120 × 180 km region in southern Alberta, Canada. We examined effects on Chestnut-collared Longspur (Calcarius ornatus) and Sprague’s Pipit (Anthus spragueii), both of which are listed as Threatened in Canada, and Savannah Sparrow (Passerculus sandwichensis), Vesper Sparrow (Pooecetes gramineus), and Western Meadowlark (Sturnella neglecta). Using piecewise regressions and generalized linear models, we estimated effects of distance from infrastructure and shallow gas well density on the habitat use and productivity of each species. We then used these analyses to quantify the availability of habitat suitable for settlement and breeding throughout our study region. Shallow gas wells, which are more abundant, affected a larger geographic area than oil wells, but oil wells were associated with the added impacts of roads. Our analyses suggest that impacts of wells on songbirds are not caused by industrial noise because individual shallow gas wells, which produce no mechanical noise, had similar impacts to noisy oil wells. Our results highlight the importance of regional plans that consider the impacts of multiple co-occurring anthropogenic features in working landscapes.

The effects of management practices on grassland birds—Sprague’s Pipit (<i>Anthus spragueii</i>)

“…Abundance declined above a gas well density of 6 wells per section (with a range from 0 to 36 well pads per km 2 ). Clutch size increased as distance to natural gas wells increased, whereas no relationship was found between clutch size and distance to oil wells or to density of wells, and no relationships were found between nest success and distance to oil or natural gas wells or to density of wells (Daniel and Koper, 2019). Ludlow and others (2015) reported that Sprague's Pipit nest locations relative to oil and gas wells did not differ from random locations.…”

“…Fewer young were fledged from successful nests near trails than nests further from trails; proximity to roads did not influence density or nest success, and no relationship was found between frequency of brood parasitism (based on a combination of all parasitized nests for the suite of songbird species evaluated) and distance to gravel roads or trails. Bernath-Plaisted and and Daniel and Koper (2019) reported no relationship between nest success and distance to nearest road; however, Daniel and Koper (2019) reported that Sprague's Pipit abundance was lower near roads, whereas clutch size was higher near roads. In lightly to moderately grazed native prairies in Saskatchewan, Sprague's Pipits were significantly more abundant alongside trails (single pairs of wheel ruts visually indistinct from surrounding habitat in terms of plant structure and composition) than alongside roads (traveling surfaces with adjacent drainage ditches planted to smooth brome and ending with a fence 11-18 m from the traveling surface) (Sutter and others, 2000).…”

“…Sprague's Pipits exhibit inconsistent responses to the presence of trails and roads. Several studies have examined the impact of trails and roads on Sprague's Pipit abundance, occurrence, nest-site selection, and productivity in southeastern Alberta (Linnen, 2008;Dale and others, 2009;Ludlow and others, 2015;Bernath-Plaisted and Koper, 2016;Nenninger and Koper, 2018;Daniel and Koper, 2019) and Saskatchewan (Sutter and others, 2000). Linnen (2008) reported that the relative abundance and occurrence of Sprague's Pipits were significantly lower 50 m from access roads than at 150, 250, 350, or 450 m from access roads; there also were significantly fewer Sprague's Pipits at 150 and 250 m from access roads than at 350 m. Dale and others (2009) indicated that Sprague's Pipit territories were negatively associated with two-track trails in grasslands; pipit territories rarely crossed these trails.…”

“…Several studies have examined the impact of oil and gas extraction in southeastern Alberta (Linnen, 2008;Dale and others, 2009;Hamilton and others, 2011;Rodgers, 2013;Bernath-Plaisted and Koper, 2016;Rodgers and Koper, 2017;Nenninger and Koper, 2018;Daniel and Koper, 2019). Linnen (2008) reported that relative abundance and occurrence were significantly lower 50 m from oil wells than at 150, 250, 350, or 450 m from oil wells; there also were significantly fewer Sprague's Pipits at 150 and 250 m from oil wells than at 350 m. Dale and others (2009) determined that Sprague's Pipit abundance decreased as density of natural gas wells increased from 1.5 to 6.2 wells per km 2 , and the species also showed an avoidance of nonnative vegetation associated with gas and oil development.…”

“…Rodgers (2013) and Rodgers and Koper (2017) reported that Sprague's Pipit abundance increased at greater distances from natural gas wells; no relationship was found between abundance and well density (ranging from 0 to 7.7 wells per km 2 ) or vegetation structure. Daniel and Koper (2019) determined that Sprague's Pipit abundance increased steadily up to 149 m from oil wells and 760 m from natural gas wells. Abundance declined above a gas well density of 6 wells per section (with a range from 0 to 36 well pads per km 2 ).…”