Clayton H. Riddell Faculty of Environment, Earth, and Resources Scholarly Works

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Open Access
Prey items and predation behavior of killer whales (Orcinus orca) in Nunavut, Canada based on Inuit hunter interviews
(2012-01-30) Ferguson, Steven H; Higdon, Jeff W; Westdal, Kristin H
Abstract Background Killer whales (Orcinus orca) are the most widely distributed cetacean, occurring in all oceans worldwide, and within ocean regions different ecotypes are defined based on prey preferences. Prey items are largely unknown in the eastern Canadian Arctic and therefore we conducted a survey of Inuit Traditional Ecological Knowledge (TEK) to provide information on the feeding ecology of killer whales. We compiled Inuit observations on killer whales and their prey items via 105 semi-directed interviews conducted in 11 eastern Nunavut communities (Kivalliq and Qikiqtaaluk regions) from 2007-2010. Results Results detail local knowledge of killer whale prey items, hunting behaviour, prey responses, distribution of predation events, and prey capture techniques. Inuit TEK and published literature agree that killer whales at times eat only certain parts of prey, particularly of large whales, that attacks on large whales entail relatively small groups of killer whales, and that they hunt cooperatively. Inuit observations suggest that there is little prey specialization beyond marine mammals and there are no definitive observations of fish in the diet. Inuit hunters and elders also documented the use of sea ice and shallow water as prey refugia. Conclusions By combining TEK and scientific approaches we provide a more holistic view of killer whale predation in the eastern Canadian Arctic relevant to management and policy. Continuing the long-term relationship between scientists and hunters will provide for successful knowledge integration and has resulted in considerable improvement in understanding of killer whale ecology relevant to management of prey species. Combining scientists and Inuit knowledge will assist in northerners adapting to the restructuring of the Arctic marine ecosystem associated with warming and loss of sea ice.
Open Access
Understanding dengue transmission by using participatory research and community-focused strategies for prevention and control in Bangladesh
(2012-05-04) Chowdhury, Parnali D; Haque, Emdad
Open Access
Adaptive learning, technological innovation and livelihood diversification: the adoption of pound nets in Rio de Janeiro State, Brazil
(2012-06-06) Idrobo, Carlos J; Davidson-Hunt, Iain J
AbstractThis paper examines the adoption of a technology to appropriate an ecologically constrained resource within the context of a restructuring fisheries sector utilising the conceptual lenses of adaptive learning and practice. Participant observation and semi-structured interviews were undertaken in the coastal community of Ponta Negra, Paraty, Rio de Janeiro, Brazil, from May 2010 to March 2011. The materials collected were translated and transcribed into English and then manually coded. Through a restorying process the English transcripts were developed into an analytical narrative that described the process of the adoption of pound nets and how this initiated a process of social differentiation between fishing households. The pound net technology constituted a new field of practice that both created and constrained opportunities for livelihood diversification. In this case, individual adaptations made to diversify household economies initiated a cascading process of social differentiation within a coastal community.
Open Access
A resource management scenario for traditional and scientific management of pink shrimp (Farfantepenaeus paulensis) in the Patos Lagoon estuary (RS), Brazil
(2013-01-11) Moura, Gustavo Goulart Moreira; Kalikoski, Daniela Coswig; Diegues, Antonio Carlos Sant’Ana
Abstract Background This article aims to discuss the incorporation of traditional time in the construction of a management scenario for pink shrimp in the Patos Lagoon estuary (RS), Brazil. To meet this objective, two procedures have been adopted; one at a conceptual level and another at a methodological level. At the conceptual level, the concept of traditional time as a form of traditional ecological knowledge (TEK) was adopted. Method At the methodological level, we conduct a wide literature review of the scientific knowledge (SK) that guides recommendations for pink shrimp management by restricting the fishing season in the Patos Lagoon estuary; in addition, we review the ethno-scientific literature which describes traditional calendars as a management base for artisanal fishers in the Patos Lagoon estuary. Results Results demonstrate that TEK and SK describe similar estuarine biological processes, but are incommensurable at a resource management level. On the other hand, the construction of a “management scenario” for pink shrimp is possible through the development of “criteria for hierarchies of validity” which arise from a productive dialog between SK and TEK. Conclusions The commensurable and the incommensurable levels reveal different basis of time-space perceptions between traditional ecological knowledge and scientific knowledge. Despite incommensurability at the management level, it is possible to establish guidelines for the construction of “management scenarios” and to support a co-management process.
Open Access
Performance of a constructed wetland in Grand Marais, Manitoba, Canada: Removal of nutrients, pharmaceuticals, and antibiotic resistance genes from municipal wastewater
(2013-03-18) Anderson, Julie C; Carlson, Jules C; Low, Jennifer E; Challis, Jonathan K; Wong, Charles S; Knapp, Charles W; Hanson, Mark L
Abstract Background The discharge of complex mixtures of nutrients, organic micropollutants, and antibiotic resistance genes from treated municipal wastewater into freshwater systems are global concerns for human health and aquatic organisms. Antibiotic resistance genes (ARGs) are genes that have the ability to impart resistance to antibiotics and reduce the efficacy of antibiotics in the systems in which they are found. In the rural community of Grand Marais, Manitoba, Canada, wastewater is treated passively in a sewage lagoon prior to passage through a treatment wetland and subsequent release into surface waters. Using this facility as a model system for the Canadian Prairies, the two aims of this study were to assess: (a) the presence of nutrients, micropollutants (i.e., pesticides, pharmaceuticals), and ARGs in lagoon outputs, and (b) their potential removal by the treatment wetland prior to release to surface waters in 2012. Results As expected, concentrations of nitrogen and phosphorus species were greatest in the lagoon and declined with movement through the wetland treatment system. Pharmaceutical and agricultural chemicals were detected at concentrations in the ng/L range. Concentrations of these compounds spiked downstream of the lagoon following discharge and attenuation was observed as the effluent migrated through the wetland system. Hazard quotients calculated for micropollutants of interest indicated minimal toxicological risk to aquatic biota, and results suggest that the wetland attenuated atrazine and carbamazepine significantly. There was no significant targeted removal of ARGs in the wetland and our data suggest that the bacterial population in this system may have genes imparting antibiotic resistance. Conclusions The results of this study indicate that while the treatment wetland may effectively attenuate excess nutrients and remove some micropollutants and bacteria, it does not specifically target ARGs for removal. Additional studies would be beneficial to determine whether upgrades to extend retention time or alter plant community structure within the wetland would optimize removal of micropollutants and ARGs to fully characterize the utility of these systems on the Canadian Prairies.
Open Access
C-Band Polarimetric Coherences and Ratios for Discriminating Sea Ice Roughness
(2013-5-22) Gupta, Mukesh; Scharien, Randall K.; Barber, David G.
The rapid decline of sea ice in the Arctic has resulted in a variable sea ice roughness that necessitates improved methods for efficient observation using high-resolution spaceborne radar. The utility of C-band polarimetric backscatter, coherences, and ratios as a discriminator of ice surface roughness is evaluated. An existing one-dimensional backscatter model has been modified to two-dimensions (2D) by considering deviation in the orientation (i.e., the slopes) in azimuth and range direction of surface roughness simultaneously as an improvement in the model. It is shown theoretically that the circular coherence () decreases exponentially with increasing surface roughness. The crosspolarized coherence () is found to be less sensitive to surface roughness, whereas the copolarized coherence () decreases at far-range incidence angles for all ice types. A complete validation of the adapted 2D model using direct measurements of surface roughness is suggested as an avenue for further research.
Open Access
Direct effects of cattle on grassland birds in Canada
(2014) Bleho, Barbara I.; Machtans, Craig; Koper, Nicola
Effects of grazing on grassland birds are generally thought to be indirect, through alteration of vegetation structure; however, livestock can also affect nest survival directly through trampling and other disturbances (e.g., livestock-induced abandonment). We extracted data on nest fates from 18 grazing studies conducted in Canada. We used these data to assess rates of nest destruction by cattle among 9 ecoregions and between seasonal and rotational grazing systems. Overall, few nests were destroyed by cattle (average 1.5% of 9132 nests). Nest destruction was positively correlated with grazing pressure (i.e., stocking rate or grazing intensity), but nest survival was higher in more heavily grazed areas for some species. Because rates of destruction of grassland bird nests by cattle are low in Canada, management efforts to reduce such destruction may not be of ecological or economic value in Canada.
Open Access
Measuring habitat fragmentation: An evaluation of landscape pattern metrics
(Wiley, 2014) Wang, Xianli; Blanchet, F. Guillaume; Koper, Nicola
Landscape patterns influence a range of ecological processes at multiple spatial scales. Landscape pattern metrics are often used to study the patterns that result from the linear and nonlinear interactions between spatial aggregation and abundance of habitat. However, many class-level pattern metrics are highly correlated with habitat abundance, making the use of these metrics as a measure of habitat fragmentation problematic. We argue that a class-level pattern metric should be (1) able to differentiate landscapes across a range of spatial aggregations, and (2) independent of habitat abundance. Based on these criteria and using both simulated and actual landscapes, we evaluated 64 class-level pattern metrics. These metrics were reclassified into four groups based on their correlation with aggregation and abundance. Among all these metrics, nine were considered robust for fragmentation measurements, which cover most of the characteristics that define pattern, including core area, shape, proximity / isolation, contrast, and contagion / interspersion.
Open Access
Grazing Intensity influences Ground Squirrel and American Badger Habitat Use in Mixed-Grass Prairies
(2014) Bylo, Lindsey, N.; Koper, Nicola; Molloy, Kelsey
Ground squirrel (Spermophilus spp.) and American badger (Taxidea taxus) burrowing activities are ecologically important disturbances that contribute to the heterogeneity of prairie environments. These activities also have a strong impact on habitat suitability for many other grassland species. However, effects of cattle grazing intensity on ground squirrel and American badger burrows are not well understood. From 2006-2012, we evaluated effects of grazing intensity and vegetation type on American badger burrow occurrence and ground squirrel burrow abundance using a manipulative grazing experiment in Grasslands National Park of Canada, Saskatchewan. The study area consisted of nine 300-ha pastures at a range of stocking rates, from very low to very high for the region. Each pasture had ten plots (six upland and four lowland) where vegetation and burrow surveys were completed. Burrow abundance and occurrence, and vegetation structure, were assessed for 2 years prior to the introduction of cattle to this landscape in 2008, which followed at least 15 years without livestock, and from 2009-2012, following introduction of livestock. Data were analyzed using generalized linear mixed models. In upland habitats, ground squirrel burrow counts increased with increasing grazing intensity and decreasing vegetation biomass; conversely, badger burrow occurrence increased with decreased stocking rates and increasing average litter cover and vegetation biomass. Abundance and occurrence of both ground squirrel and badger burrows in lowland habitats was relatively independent of grazing intensity or vegetation. Vegetation composition had little impact on ground squirrel or badger burrows. A range of grazing intensities may contribute to maintaining diversity of burrowing mammals in prairie environments.
Open Access
Optimizing Repeat-Visit, Call-Broadcast Nocturnal Surveys for Yellow Rails (Coturnicops noveboracensis)
(The Waterbird Society, 2014) Martin, Kristen; Koper, Nicola; Bazin, Ron
Due to its secretive nature and nocturnal vocalization, multi-species bird monitoring programs are not effective in surveying populations of Yellow Rails (Coturnicops noveboracensis) and, thus, species-speciﬁc survey methods should be used. To determine how to optimize nocturnal call-playback surveys of Yellow Rails, we evaluated the effects of survey methods (naïve-estimated vs. detectability-adjusted estimated occupancy, observer, number of surveys, and the use of playbacks) and temporal and environmental conditions (e.g., time, date, temperature, moon phase, seasonality, and cloud cover) on detection probability. In 2010 and 2011, 334 call-broadcast night surveys for Yellow Rail were conducted at 167 survey points within 80 wetlands in south-central Manitoba, Canada. Yellow Rail detection probability was estimated at 0.63 in both years. In 2010, the detectability-adjusted wetland occupancy rate was estimated at 0.63, and in 2011 it was estimated at 0.36. Call-broadcast surveys contributed relatively little to improving Yellow Rail detectability, but repeat surveys at each site increased the number of individuals detected. Detection probability was not correlated with the temporal or environmental variables we studied, or by observer. Surveys where call-broadcasts are not feasible, such as volunteer surveys, are still likely to result in good estimates of Yellow Rail abundances, if surveys are repeated within breeding seasons.
Open Access
Assessing the Breeding Success of the Western Grebe (Aechmophorus occidentalis) After 40 Years of Environmental Changes at Delta Marsh, Manitoba
(The Waterbird Society, 2014) La Porte, Nicholas; Koper, Nicola; Leston, Lionel
Since the 1970s, artiﬁcially stabilized water levels, increased presence of common carp (Cyprinus carpio) and invasion by a cattail hybrid (Typha glauca) have changed the nesting environment for Western Grebes (Aechmophorus occidentalis) at Delta Marsh, Manitoba. To evaluate the impact of these changes, nest survival rates, causes of nest mortality, wind conditions, locations of nests and vegetation structure at nests in 2009-2010, and chick-adult ratios were compared to similar data for Western Grebes at Delta Marsh from 1973-1974. Apparent nest survival rates were lower in 2009-2010 than 1973-1974, and between low-water years (1973, 2010) and high-water years (1974, 2009). Lower apparent nest survival rates in 2009-2010 (49% in 2009 and 43% in 2010, compared to 46% in 1973 and 84% in 1974), and chick-adult ratios (0.55 in 1973 and 0.88 in 1974, compared to 0.55 in 2009 and 0.39 in 2010) were attributed to increases in destruction of nests primarily by wave action and secondarily by common carp, which were not observed destroying Western Grebe nests in 1973-1974. The replacement of native bulrushes by cattails in Western Grebe nesting habitat may have caused the observed increase in proximity to openwater edge, and this proximity may have increased destruction of nests by waves. Restoring stands of emergent bulrush by varying marsh water levels and reducing carp in the marsh might improve nest survival of Western Grebes.
Open Access
Microwave Emission and Scattering from Ocean Surface Waves in the Southern Beaufort Sea
(2014-3-10) Gupta, Mukesh; Scharien, Randall K.; Barber, David G.
Estimates of the relationships between geophysical variables and microwave backscatter/emission are important for the evaluation of atmosphere-ocean interaction, as well as energy, and mass transfer across this interface. We evaluate ship-based passive microwave brightness temperatures at 37 and 89 GHz and active polarimetric backscatter at 5.5 GHz (C-band), as these relate to buoy-derived ocean wave parameters for distinct wave regimes in the southern Beaufort Sea. Microwave emission and backscatter are shown to be sensitive to the ocean surface physical roughness as defined by the significant wave height , compared to wind speed. The shows significant correlation with , with the strongest correlation for the H-polarization channel at 37 and 89 GHz. Active co- and cross- polarization ratios at 40° incidence angle are associated with , with the increase proportional to . The polarimetric coherence parameter at 20° also shows an inverse relationship with because of an expected decorrelation of complex returns with greater surface roughness.
Open Access
A New Trophic State Index for Lagoons
(2014-3-9) Gupta, Mukesh
This paper proposes a new nitrogen-based trophic state index (TSI) for the estimation of status of eutrophication in a lagoon system. Nitrite-nitrogen (NO2-N) is preferable because of its greater abundance in Chilika lagoon and its relation to other criteria of trophic state, for example, chlorophyll-a (Chl-a) and Secchi disk depth (SDD). Nitrite is preferable over nitrate because the former decreases the fluorescence and affects photosynthesis, thereby controlling primary production. This paper also computes TSI using Chl-a and SDD. The three parameters account for the biological, chemical, and physical characteristics of the lagoon. It will be possible to estimate the TSI of freshwater and brackish water lagoons and other water bodies using the new expressions taking into consideration the spatial and temporal variability in the dataset. Depending on the data availability, alternative TSI (Chl-a) and TSI (SDD) can account for the biological and physical contributions to eutrophication. The estimated TSI can account for Chl-a and NO2-N up to 322.18 mg m−3 and 61.99 μg L−1, respectively. The TSI based on these three parameters can serve as a complimentary and predictive tool for lagoon management and field programs to monitor the health of a lagoon.
Open Access
Growth, sexual maturity, and reproduction of a female Midland Painted Turtle (Chrysemys picta marginata) afflicted with kyphosis
(2015) MOLDOWAN, Patrick, D.; KEEVIL, Matthew, G.; Koper, Nicola; Brooks, Ronald, J.; Litzgus, Jacqueline, D.
Kyphosis, a congenital humpback condition of the spinal column, has been reported across a broad range of chelonian taxa. These reports are often of single observations and lack background information about the history of the animal(s) involved. A kyphotic female Midland Painted Turtle (Chrysemys picta marginata) reported herein is a member of a long-term mark-recapture study in Algonquin Park (Ontario, Canada), providing a unique opportunity to document life-history characters of a kyphotic turtle over 18 years, and to draw comparisons to other members of her cohort and population. Despite this spinal deformity, the somatic growth, body size, age at sexual maturity, and reproduction of the kyphotic female are similar to those of normal (non-kyphotic) females in our long-term study population. This suggests that the condition has not compromised her fitness.
Open Access
Managing Mixed-grass Prairies for Songbirds Using Variable Cattle Stocking Rates
(Elsevier, 2015) Sliwinski, M.S.; Koper, N.
Most remaining grasslands are used for livestock grazing; stocking rates could be managed to help stop declining songbird populations. We examined the effects of stocking rates on grassland songbirds in northern mixed-grass prairies using a beyond Before-After-Control-Impact manipulative experiment in Canada’s Grasslands National Park and adjacent community pastures. The study area consisted of nine 300-ha pastures grazed at a range of stocking rates starting in 2008. We conducted songbird surveys at six upland plots in each pasture from 2006‒2010, and measured vegetation structure within each plot from 2008‒2010 (n = 54). We evaluated the effects of stocking rates on habitat structure and songbird abundance using linear and generalized linear mixed models. Baird’s sparrow (Ammodramus bairdii) relative abundance declined with increasing stocking rates. Chestnut-collared longspur (Calcarius ornatus) relative abundance increased only at higher stocking rates indicating a possible threshold effect. Savannah sparrow (Passerculus sandwichensis) relative abundance decreased with stocking rates above 0.4 AUM after a year of grazing. Sprague’s pipit (Anthus spragueii) relative abundance declined with grazing, but the effect was weak and only significant in one year. Western meadowlark (Sturnella neglecta) abundance was unaffected by grazing. Stocking rates may be used to benefit grassland songbirds and may alter avian communities after as little as one month of livestock grazing. Applying a range of stocking rates regionally may provide habitat for many species.
Open Access
Effects of Weather and Land Management on the Western Prairie Fringed-orchid (Platanthera praeclara) at the Northern Limit of its Range in Manitoba, Canada
(2015) Bleho, Barbara I.; Koper, Nicola; Borkowsky, Christie L.; Hamel, Cary D.
The western prairie fringed-orchid is a rare North American orchid restricted to a few remnants of wet to mesic tallgrass prairie. It is federally listed in both Canada and the United States and both countries have developed a recovery plan for the species. Two key management objectives are to monitor population trends and identify beneficial management practices. We used 21 y of data from the Manitoba metapopulation to assess effects of weather and land management on this species. Our results suggest the metapopulation in Manitoba is relatively stable. Western prairie fringed-orchids appear to benefit most from a combination of warm temperatures in the previous growing season followed by cool snowy but short winters and wet springs. Periodic burning ( e.g., every 2-3 y) may benefit fringed-orchids, whereas grazing may be detrimental. This was not a controlled experiment, however, and gaps in the data may have influenced our results. Prescribed burning is a viable management tool for curtailing woody invasion and both burning and grazing reduce litter and grass cover, but careful consideration of timing, frequency, and intensity of application is required so management does not hinder fringed-orchid reproduction or reduce survival, while also recognizing management requirements may vary among years depending on weather. Long-term studies are particularly valuable for the western prairie fringed-orchid due to its erratic life cycle and fluctuating populations, which complicate studies of environmental and management effects on this species.
Open Access
Impact of Continuous Cropping on the Diurnal Range of Dew Point Temperature during the Foliar Expansion Period of Annual Crops on the Canadian Prairies
(2015-12-29) Shrestha, Bharat M.; Raddatz, Richard L.; Desjardins, Raymond L.; Worth, Devon E.
It is important to increase our knowledge of the role of land use in changing the regional climate. This study asked, “Has the increase in continuous cropping over the past 50 years on the Canadian Prairies influenced the daily mean and range of morning dew point temperatures during the foliar expansion period (from mid-June to mid-July) of annual field crops?” We found that there has been a general increase in the decadal average of mean daily and in the range of morning from the 1960s to the 2000s. The increase in the observed range of between the daily minimum value, which typically occurs near sunrise, and the late morning peak was found to be related to the increase in annual crop acreage and consequent decrease in summerfallow area. The relationship was more significant in the subhumid climatic zone than in the semiarid climatic zone, and it was influenced by whether the region was experiencing either wet, normal, or dry conditions.
Open Access
Model-Based Pseudo-Quad-Pol Reconstruction from Compact Polarimetry and Its Application to Oil-Spill Observation
(2015-7-26) Yin, Junjun; Moon, Wooil; Yang, Jian
Compact polarimetry is an effective imaging mode for wide area observation, especially for the open ocean. In this study, we propose a new method for pseudo-quad-polarization reconstruction from compact polarimetry based on the three-component decomposition. By using the decomposed powers, the reconstruction model is established as a power-weighted model. Further, the phase of the copolarized correlation is taken into consideration. The phase of double-bounce scattering is closer to π than to 0, while the phase of surface scattering is closer to 0 than to π. By considering the negative (double-bounce reflection) and positive (surface reflection) copolarized correlation, the reconstruction model for full polarimetry has a good consistency with the real polarimetric SAR data. -band ALOS/PALSAR-1 fully polarimetric data acquired on August 27, 2006, over an oil-spill area are used for demonstration. Reconstruction performance is evaluated with a set of typical polarimetric oil-spill indicators. Quantitative comparison is given. Results show that the proposed model-based method is of great potential for oil-spill observation.
Open Access
Cattle stocking rate and grazing duration effects on songbird nest survival vary by species in mixed-grass prairies
(Elsevier, 2016) Pipher, Emily; Curry, Claire M.; Koper, Nicola
Grassland bird species are declining more quickly than birds of any other biome in North America, but the effects of the most widespread use of native mixed-grass prairies, livestock grazing, on nest survival of songbirds is not well understood. We used an adaptive management grazing experiment in southwestern Saskatchewan to evaluate effects of cattle stocking rate and number of years grazed on nest survival of five songbird species in 2009 and 2010. Two 300-m² plots were located in each of 12 pastures. Three pastures were ungrazed controls, while the remaining pastures had stocking rates ranging from 0.23-0.83 Animal Unit Months (AUM) · ha-1 (very low to very high for this region), and were grazed for 2-3 or >15 years. Analyses were conducted using logistic exposure regression. We found few effects of grazing on nest survival. Exceptions to this pattern were that the lowest nest survival rates occurred at low-moderate grazing intensities with fewer years grazed for Sprague’s pipits (Anthus spragueii) in 2009, at low grazing intensities and longer grazing durations for chestnut-collared longspurs in 2009, and at moderate grazing intensities regardless of grazing duration for vesper sparrows in 2010. Cumulatively, our results suggest that in the short term, a wide range of grazing intensities are consistent with the conservation of grassland songbirds, and that a mosaic of grazing intensities across the prairie landscape would provide preferred habitat types for a variety of songbird species.
Open Access
PHYSICAL FOOTPRINT OF OIL AND GAS INFRASTRUCTURE, NOT ANTHROPOGENIC NOISE, REDUCES NESTING SUCCESS OF SOME GRASSLAND SONGBIRDS
(Elsevier, 2016) Bernath-Plaisted, Jacy; Koper, Nicola
Western North America’s grasslands have undergone a rapid expansion of conventional oil and natural gas development, the effects of which are largely unknown for nesting songbirds. Understanding mechanisms that drive ecological responses to infrastructure is essential for our ability to identify and minimize potential negative effects on wildlife. Our study sought to distinguish between effects driven by physical structures and those driven by associated anthropogenic noise. Further, we evaluated whether some structure types have smaller ecological footprints than others. We monitored 747 grassland songbird nests, of five species, in Alberta’s mixed-grass prairie to determine if, and why, the presence of infrastructure affects nesting success. Nesting success was significantly lower at infrastructure sites relative to controls for both Savannah sparrow (Passerculus sandwichensis) and vesper sparrow (Pooecetes gramineus), as well as at screwpump relative to pumpjack oil wells. There was no correlation between nesting success and noise intensity, and nesting success was not significantly lower near roads. However, nesting success was lower at electric grid-powered sites relative to generator-powered sites, suggesting that power distribution lines may benefit some nest predators. Vesper sparrow nest density increased with proximity to oil wells and compressor stations, so it is possible that these sites are ecological traps for this species. Management strategies focusing only on reduction of anthropogenic noise and disturbance may be ineffectual for conservation of grassland songbirds. Managers should also seek to reduce the physical footprint of infrastructure on the landscape, replace screwpumps with pumpjacks, and replace grid powered with generator-powered wells.

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