Search

This paper traces the history of Caragana arborescens, a shrub which has flourished for a hundred years in the polluted industrial landscape of Mill Creek Ravine, Edmonton. While now considered an invasive plant, caragana was once viewed as a vitally important species in the colonial settlement and transformation of the Canadian prairies. Arguing against the view of caragana as simply an extension of settler colonialism, or as an embodiment of industrial abandonment, I posit that caragana can be better thought of as a monstrous disturbance: a dense node of bodies and historical relations which emerged out of an experimental colonial project and thrives in the degraded landscapes that industrial capitalism has wrought. As a monstrous disturbance, caragana's growth recollects, extends, and troubles the experimental colonial project that brought it to Mill Creek Ravine. [ABSTRACT FROM AUTHOR]

In Prairie Falcons (Falco mexicanus), females are considerably larger than males, as in most diurnal birds of prey. This phenomenon, known as reversed sexual dimorphism (RSD), is usually associated with asymmetry in parental care: the smaller male provides most of the food during the nesting season, whereas the larger female incubates the eggs, and broods and protects the young. To evaluate this relationship in Prairie Falcons, we quantitatively assessed parental roles of 52 pairs of Prairie Falcons nesting in southwestern Idaho, over a 4-yr period (1984–1987). We collected behavioral observations for each pair, from the establishment of a nesting territory until young were 30–35 d old (fledging age), for a total of 613 observation days (9089 hr). We found that male and female falcons shared some tasks, although not necessarily equally, including incubation, provisioning prey and nest defense. Females accounted for two-thirds of the diurnal incubation responsibility and males for one-third. Males and females made comparable efforts in food provisioning; similarly, nest defense, here defined as aggressive interactions with (potential) nest predators, did not differ between the sexes. Other behaviors, such as brooding, hunting, and nest attendance were performed more by one sex than the other. Brooding was carried out primarily by females, and they showed consistently higher nest attendance compared to males. Males hunted significantly more than females and delivered most prey items to the nest site. Overall, sex roles exhibited by nesting Prairie Falcons in our study largely agreed with predictions based on RSD. En Falco mexicanus, al igual que en la mayoría de las aves rapaces diurnas, las hembras son considerablemente más grandes que los machos. Este fenómeno, conocido como dimorfismo sexual inverso (DSI), generalmente se asocia con asimetría en el cuidado parental: el macho, de menor tamaño que la hembra, proporciona la mayor parte del alimento durante la temporada de nidificación, mientras que la hembra más grande incuba los huevos, abriga y protege a los pollos. Para evaluar esta relación en F. mexicanus, evaluamos cuantitativamente los roles parentales de 52 parejas que nidificaron en el suroeste de Idaho durante un período de 4 años (1984–1987). Recolectamos observaciones de comportamiento para cada pareja desde el establecimiento de un territorio de nidificación hasta que los pollos tuvieron 30–35 días de edad (edad de emplumamiento), durante un total de 613 días de observación (9089 horas). Encontramos que los machos y las hembras de F. mexicanus compartieron algunas tareas, aunque no necesariamente por igual, tales como la incubación, el suministro de presas y la defensa del nido. Las hembras realizaron dos tercios de la incubación diurna y los machos un tercio. Los machos y las hembras hicieron esfuerzos comparables en el suministro de alimento; de manera similar, la defensa del nido, aquí definida como interacciones agresivas con (potenciales) depredadores del nido, no difirió entre los sexos. Otros comportamientos, como el cuidado de la nidada, la caza y la asistencia al nido fueron realizados más por un sexo que por el otro. El cuidado de la nidada fue realizado principalmente por las hembras, las que mostraron una asistencia al nido consistentemente más alta en comparación con los machos. Los machos cazaron significativamente más que las hembras y entregaron la mayoría de las presas al nido. En general, los roles de sexo exhibidos por los individuos de F. mexicanus que nidificaron en nuestro estudio concordaron en gran medida con las predicciones basadas en el DSI. [Traducción del equipo editorial] [ABSTRACT FROM AUTHOR]

Evaluating leukocytes provides insight in the overall health of animals by characterizing pathologies related to infection, inflammation, and stress. In reptile species, many leukocyte quantification methods are used to evaluate white blood cell (WBC) parameters; however, agreement and analytical variability (repeatability) between the various methods have yet to be reported and critically assessed in many species, including the prairie rattlesnake (Crotalus viridis). The objectives of this study were to 1) test agreement between hematology parameters determined by phloxine-based stain (Eosinophilic leukopet, EO), Natt–Herrick's (NH), and estimate (EST) methods using fresh whole blood and lithium-heparinized blood; 2) determine the agreement between estimates from a veterinary student and from a board-certified clinical pathologist; and 3) determine the analytical variability of EO, NH, and EST methods. Venipuncture was performed in 27 adult snakes, and agreement was then assessed using Bland–Altman plots and Passing–Bablock regression between all methods. There was a variable degree of proportional and constant error between many of the quantification methods, but descriptive statistics for all methods fell within biologically relevant values. There was good agreement in the EST method between the clinical pathologist and the veterinary student, but the student had a significantly higher mean WBC count in fresh whole blood. The lowest analytical variability was observed with the NH method (15.4%), whereas the highest was observed with the EST method (58.6% for the clinical pathologist, 59.4% for the veterinary student). These results identify the intrinsic variability in reptile hematological methods currently used and emphasize the need to develop a singular diagnostic standard for leukocyte quantification in reptile species. [ABSTRACT FROM AUTHOR]

In ecological restoration, seed sourcing is often among the first and most critical steps in achieving restored populations that establish and reproduce successfully, while also having the genetic capacity to adapt to future change. Many approaches have been proposed to guide seed sourcing for restoration, including a strong focus on local seed sources, the use of assisted gene flow or assisted migration, and regional admixture provenancing. The goal of this research was to evaluate these issues in the context of grassland restoration. We collected seed of Chamaecrista fasciculata, an annual native to the prairies of North America, from four locations along a latitudinal gradient. We generated inter‐ and intrapopulation crosses and grew them in two common gardens located in restored prairies in southeast Minnesota. We found that northern populations tended to flower and fruit earlier than southern populations, while hybrids generally had intermediate phenologies. There were strong fitness benefits of hybridization, particularly among the local crosses. However, the plants grown from our southernmost seed source produced few mature seed pods in the common gardens before the advent of fall frost, suggesting that translocating populations across significant latitudinal distances may be problematic. Taken together, our findings support a regional admixture provenancing approach while indicating that assisted migration and assisted gene flow across latitudinal distances of three degrees or more compromises fitness in this species. [ABSTRACT FROM AUTHOR]

We investigated the plant species diversity, community assemblage, net primary production and soil carbon sequestration in an old field (OF), which went through passive restoration with spontaneous secondary succession, and a restored prairie (RP), which went through active restoration with reintroduction of native plants. The passive restoration in OF did not attain as high diversity and richness of plant species as did in RP. Our NMS (nonmetric multidimensional scaling) ordination revealed a clear divergence of RP and OF vegetation with dissimilar species compositions to separate paths of succession trajectory. The spontaneous succession in OF has made very little progress due to a potentially strong inhibitory priority effect of invasive plants. The belowground biomass in the high‐diversity RP was 1.3× higher than the low‐diversity OF. We found no measurable difference in soil C sequestration between RP and OF at this time, possibly due to edaphic factors, lack of legumes, or both. Human intervention is needed for restoring abandoned croplands—highly disturbed, fragmented and isolated habitats—to tallgrass prairies in the U.S. Midwest. Our recommended intervention includes but is not limited to removal of exotic plants, further augmentation of native plants (particularly legumes), and periodic burns. [ABSTRACT FROM AUTHOR]

Restoration efforts often focus on changing the composition and structure of invaded plant communities, with two implicit assumptions: (1) functional interactions with species of other trophic levels, such as pollinators, will reassemble automatically when native plant diversity is restored and (2) restored communities will be more resilient to future stressors. However, the impact of restoration activities on pollinator richness, plant-pollinator interaction network structure, and network robustness is incompletely understood. Leveraging a restoration chronosequence in Pacific Northwest prairies, we examined the effects of restoration-focused prescribed fire and native forb replanting on floral resources, pollinator visitation, and plant-pollinator network structure. We then simulated the effects of plant species loss/removal scenarios on secondary extinction cascades in the networks. Specifically, we explored three management-relevant plant loss scenarios (removal of an abundant exotic forb, removal of an abundant forb designated a noxious weed, and loss of the rarest native forb) and compared them to control scenarios. Pyrodiversity and proportion of area recently burned increased the abundance and diversity of floral resources, with concomitant increases in pollinator visitation and diversity. Pyrodiversity also decreased network connectance and nestedness, increased modularity, and buffered networks against secondary extinction cascades. Rare forbs contributed disproportionately to network robustness in less restored prairies, while removal of typical "problem" plants like exotic and noxious species had relatively small impacts on network robustness, particularly in prairies with a long history of restoration activities. Restoration actions aimed mainly at improving the diversity and abundance of pollinator-provisioning plants may also produce plant-pollinator networks with increased resilience to plant species losses. [ABSTRACT FROM AUTHOR]

This article features a conversation between landscape architects Patrick Blanc and Catherine Mosbach. They discuss their experiences working on various projects and the importance of creating spaces that are open to different populations and practices. Blanc emphasizes the need to protect natural habitats and species in order to allow them to adapt to climate change. Mosbach highlights the importance of interdisciplinary knowledge and learning from both contemporary and historical works. They both express excitement about their current projects and the opportunity to continue learning and exploring new plant species. [Extracted from the article]

This article explores the lessons that can be learned from plants, specifically in relation to stress recognition and response. The author observes signs of stress in certain plants within a prairie community and contrasts how humans tend to focus on personal deficits when individuals exhibit stress, while plants prioritize identifying and addressing environmental factors. The author suggests that adopting a mindset of growth and thriving when engaging with fellow humans, similar to how we approach plants, could lead to positive transformations in human communities. The article also delves into the science of dendrochronology, which involves reading tree rings to understand climate patterns and tree age. It examines the historical and cultural significance of ancient trees and their veneration in various periods and cultures. The author expresses concerns about the modern tendency to quantify and measure trees, emphasizing the need to value trees beyond their instrumental use. The text further discusses the importance of preserving old trees in urban environments and designing cities that can support the growth of large and old trees in the face of climate change. It introduces the concept of "elderflora" and explores the factors contributing to tree longevity, highlighting the bias in dendrochronology towards certain plants and the exclusion of succulents. The text also emphasizes the significance of small-scale care for trees in cultural sites like temples and shrines. It discusses the role of botanic gardens in conservation and education, particularly in preserving genetic diversity. The article mentions California's efforts to preserve giant sequoias and touches on the aesthetics of longevity in bonsai. It acknowledges [Extracted from the article]

A central goal of ecological restoration is to promote diverse ecosystems dominated by native species, but restorations are often plagued by exotic species. A better understanding of factors underlying positive correlations between native and exotic species richness, a pattern that is nearly ubiquitous at large scales in plant communities, may help managers modify these correlations to favor native plant species during restoration. Across 29 tallgrass prairie sites restored through seed sowing onto former agricultural lands, we examined whether the relationship between native and exotic richness is (1) altered by management, such as seed additions and prescribed fire; (2) controlled instead by environmental conditions and successional processes; or (3) altered by management in certain environments and not in others. As is commonly found, native and exotic richness were positively correlated at large scales (i.e., across sites) in this study. Management actions explained much of the remaining variation in native richness, while environmental conditions explained very little. Sites sown with more species at higher seeding rates, especially forb species, had higher native richness than predicted by the native–exotic richness relationship. In contrast, native richness was lower in older restorations than predicted by the native–exotic richness relationship, because native richness, and not exotic richness, declined with restoration age. We show that management actions such as seed sowing can modify the native–exotic richness relationship to favor native species during restoration. The development of management actions that mitigate native species richness declines over time will further benefit native species restoration. [ABSTRACT FROM AUTHOR]

Sexual bonds are central to the social lives of many species, including humans, and monogamous prairie voles have become the predominant model for investigating such attachments. We developed an automated whole-brain mapping pipeline to identify brain circuits underlying pair-bonding behavior. We identified bonding-related c-Fos induction in 68 brain regions clustered in seven major brain-wide neuronal circuits. These circuits include known regulators of bonding, such as the bed nucleus of the stria terminalis, paraventricular hypothalamus, ventral pallidum, and prefrontal cortex. They also include brain regions previously unknown to shape bonding, such as ventromedial hypothalamus, medial preoptic area, and the medial amygdala, but that play essential roles in bonding-relevant processes, such as sexual behavior, social reward, and territorial aggression. Contrary to some hypotheses, we found that circuits active during mating and bonding were largely sexually monomorphic. Moreover, c-Fos induction across regions was strikingly consistent between members of a pair, with activity best predicted by rates of ejaculation. A novel cluster of regions centered in the amygdala remained coordinated after bonds had formed, suggesting novel substrates for bond maintenance. Our tools and results provide an unprecedented resource for elucidating the networks that translate sexual experience into an enduring bond. [ABSTRACT FROM AUTHOR]

Species distribution models are useful conservation planning tools for at-risk species, especially if they are linked to planning efforts, conservation delivery, and a changing environment. The Dakota skipper (Hesperia dacotae) is an endemic butterfly of mixed and tallgrass prairie of the northern Great Plains that is listed as federally threatened in the United States and Canada. We modeled broad-scale habitat suitability for the Dakota skipper by relating occurrence observations collected via non-probabilistic population surveys and a stratified sample of pseudo-absences to environmental predictors using a machine learning approach (i.e. Random Forest classification model). Predictors were summarized at two local scales and one landscape scale to reflect a potential spatial hierarchy of settlement responses. We used recursive feature elimination to select the top 25 covariates from a suite of predictor variables related to climate, topography, vegetation cover, biomass, surface reflectance, disturbance history, and soil characteristics. The top model included six bioclimatic, one soil, and 18 local- and landscape-scale vegetation variables and indicated an association with undisturbed grasslands with higher perennial grass and forb cover and biomass. The model performed well, with kappa and AUC estimates of 0.92 and 0.99, respectively, for 20% of data withheld for validation. To understand how climate change might affect Dakota skipper distribution, we applied the model using future 30-year bioclimatic predictions. Predicted suitable habitat declined and the climate envelope associated with Dakota skipper occurrence shifted north into Canada. While it is unknown to what degree the bioclimatic relationships in the model are biologically meaningful or are simply correlative with our non-probabilistic sample of occurrences, our results present an urgency to improve data collection for Dakota skipper populations and better understand climatic relationships, as climate change could have profound effects on populations and conservation planning. Regardless of climate or model uncertainty, our results demonstrate the importance of maintaining sufficient quantities and quality of grass on the landscape to support populations of Dakota skipper. [ABSTRACT FROM AUTHOR]

Covid-19 lockdowns provided ecologists with a rare opportunity to examine how animals behave when humans are absent. Indeed many studies reported various effects of lockdowns on animal activity, especially in urban areas and other human-dominated habitats. We explored how Covid-19 lockdowns in Israel have influenced bird activity in an urban environment by using continuous acoustic recordings to monitor three common bird species that differ in their level of adaptation to the urban ecosystem: (1) the hooded crow, an urban exploiter, which depends heavily on anthropogenic resources; (2) the rose-ringed parakeet, an invasive alien species that has adapted to exploit human resources; and (3) the graceful prinia, an urban adapter, which is relatively shy of humans and can be found in urban habitats with shrubs and prairies. Acoustic recordings provided continuous monitoring of bird activity without an effect of the observer on the animal. We performed dense sampling of a 1.3 square km area in northern Tel-Aviv by placing 17 recorders for more than a month in different micro-habitats within this region including roads, residential areas and urban parks. We monitored both lockdown and no-lockdown periods. We portray a complex dynamic system where the activity of specific bird species depended on many environmental parameters and decreases or increases in a habitat-dependent manner during lockdown. Specifically, urban exploiter species decreased their activity in most urban habitats during lockdown, while human adapter species increased their activity during lockdown especially in parks where humans were absent. Our results also demonstrate the value of different habitats within urban environments for animal activity, specifically highlighting the importance of urban parks. These species- and habitat-specific changes in activity might explain the contradicting results reported by others who have not performed a habitat specific analysis. [ABSTRACT FROM AUTHOR]

Grazing management is a critical land-use requirement that facilitates the preservation of plant community composition, soil properties and environmental quality. Grazing density of livestock has a significant impact on soil health, and there is a need to study the interactions of grazing densities and topographical positions influencing soil biochemical and microbial properties. This study was conducted at Cottonwood Field Station in Philip, South Dakota to assess the influence of more than 7 years of low, medium, and high grazing stocking densities (0.33, 0.41, 0.72 animal units/ac, respectively) at summit and footslope landscape positions on soil carbon (C) and nitrogen (N) fractions, microbial community composition, and enzymatic activities in a mixed-grass prairie ecosystem. Medium grazing density showed a 16% increase in soil N at the footslope compared with summit. Low grazing density significantly reduced microbial biomass C (~269 µg g-1 soil) and N (~26 µg g-1 soil) at summit compared with other grazing densities and landscape positions, except, the summit at high grazing density. Medium grazing density significantly enhanced hot-water extractable N by 21-23% at footslope compared with low grazing density at the footslope and high grazing density at the summit. Low grazing density increased urease (3.64 µg NH4+ g-1 soil h-1) at footslope than all other grazing densities and landscape positions. Low grazing density enhanced β-glucosidase by 75% than high grazing density; alkaline phosphatase was significantly greater by 60% at footslope than summit. High grazing density at the summit decreased total PLFA (mean 56.53 nmol g-1 soil) due to lower AM fungi, G (+), G (-) and actinomycetes biomass. Microbial stress indicators such as G (+)/G (-), saturated/unsaturated, monosaturated/polysaturated, GNeg stress revealed that high grazing density especially at summit position posed elevated physiological stressed conditions to the microbial community. Overall, long-term medium grazing density of 0.41 animal units/ac may enhance soil N, microbial composition, microbial biomass C and N, hot-water extractable C and N fractions, and reduce stress conditions for microbial community at both footslope as well as summit landscape positions. Moreover, long-term overgrazing of pastures, particularly at summit slopes, appears to inhibit microbial populations and degrade overall soil health. [ABSTRACT FROM AUTHOR]

Conservation translocations are frequently inhibited by extensive dispersal after release, which can expose animals to dispersal‐related mortality or Allee effects due to a lack of nearby conspecifics. However, translocation‐induced dispersals also provide opportunities to study how animals move across a novel landscape, and how their movements are influenced by landscape configuration and anthropogenic features. Translocation among populations is considered a potential conservation strategy for lesser prairie‐chickens (Tympanuchus pallidicinctus). We determined the influence of release area on dispersal frequency by translocated lesser prairie‐chickens and measured how lesser prairie‐chickens move through grassland landscapes through avoidance of anthropogenic features during their dispersal movements. We translocated 411 lesser prairie‐chickens from northwest Kansas to southeastern Colorado and southwestern Kansas in 2016–2019. We used satellite GPS transmitters to track 115 lesser prairie‐chickens throughout their post‐release dispersal movements. We found that almost all lesser prairie‐chickens that survived from their spring release date until June undergo post‐translocation dispersal, and there was little variation in dispersal frequency by release area (96% of all tracked birds, 100% in Baca County, Colorado, 94% in Morton County, Kansas, n = 55). Dispersal movements (male: 103 ± 73 km, female: 175 ± 108 km, n = 62) led to diffusion across landscapes, with 69% of birds settling >5 km from their release site. During dispersal movements, translocated lesser prairie‐chickens usually travel by a single 3.75 ± 4.95 km dispersal flight per day, selecting for steps that end far from roads and in Conservation Reserve Program (CRP) grasslands. Due to this "stepping stone" method of transit, landscape connectivity is optimized when <5 km separates grassland patches on the landscape. Future persistence of lesser prairie‐chicken populations can be aided through conservation of habitat and strategic placement of CRP to maximize habitat connectivity. Dispersal rates suggest that translocation is better suited to objectives for regional, rather than site‐specific, population augmentation for this species. [ABSTRACT FROM AUTHOR]

One important goal in prairie restorations is to have forb species that flower throughout the growing season (i.e. a range of flowering phenology). We conducted an experiment to test whether three early‐ and three late‐flowering forb species are seed or recruitment limited, if mowing can influence this limitation, and if forb additions will impact overall plant diversity in ongoing restorations.The experiment was conducted at two restorations in northern Iowa and one in southern Minnesota, USA, using a split‐plot design. Whole plots tested the effect of mowing, and subplots tested the effect of target forbs being added as seeds or small transplants at varied richness levels (0, 1, 3 or 6 species added). Control plots received no forb additions. To compare establishment success, we estimated target species biomass, survivorship and per cent cover of target species across 3 years (2019–2021). Plant diversity measures (richness, inverse Simpson's diversity) were estimated within subplots to determine whether forb additions impacted diversity.Biomass and relative abundance of early‐ and late‐flowering forbs was much higher when they were added as transplants than when added as seeds. Survivorship across life stages indicated that the transition from seed to adult had lower survivorship probabilities (0.6%) than the transition from transplant (juvenile) to adult (75%).Plant diversity of these ongoing restorations was higher when target forbs were added compared to controls. Diversity was higher when target forbs were transplanted (8.4 species/plot and inverse Simpson's diversity of 4.0) than when they were seeded (7.6 species/plot and inverse Simpson's diversity of 3.8). Early‐flowering treatments increased diversity more than late‐flowering treatments, and diversity increased linearly with the number of forb species added.Mowed and unmowed plots had similar levels of target species establishment and plant diversity.Synthesis and applications: Our results indicate that early‐ and late‐flowering species are more recruitment limited than seed limited and that diversity is lower when these species are missing in restorations. We recommend transplanting a rich mix of early‐ and late‐flowering forbs to increase their biomass and ensure that flowering occurs throughout the growing season. [ABSTRACT FROM AUTHOR]

Root hemiparasites infiltrate the vascular tissue of host roots to acquire water and nutrients, which often reduces host growth. Hemiparasites are postulated to be keystone species in grassland communities if they suppress dominant species and increase plant community biodiversity, and ecosystem engineers if they increase nutrient accessibility for surrounding species. We examined keystone effects by evaluating species richness and evenness in 1 m2 plots in a recent prairie restoration where Castilleja sessiliflora was naturally present or absent, and in a longer-established prairie restoration with or without Pedicularis canadensis. We examined ecosystem engineer effects by determining nitrate and phosphate concentrations under, 25 cm from, and 50 cm from hemiparasites, and in the center of hemiparasite-free plots. On the C. sessiliflora site, plots with the hemiparasites had higher species richness due to more forbs and higher floristic quality, consistent with the keystone species hypothesis. Soil phosphate levels were also greater in plots with C. sessiliflora present, consistent with the hypothesis of ecosystem engineering by this hemiparasite. In contrast, plots with/without P. canadensis showed no associations of any community metrics with the hemiparasite, and no correspondence between the presence of hemiparasites and soil nutrients. Although hemiparasites can increase grassland community heterogeneity, the effect is not universal, and the direction and strength of effects likely depends on local conditions. [ABSTRACT FROM AUTHOR]

Climate change is altering biodiversity of ecosystems worldwide by causing shifts in species' home ranges, potential extinctions of species, and Extreme Climatic Events (ECEs), such as hurricanes and extreme temperatures. The purpose of this study was to examine effects of two extreme weather events on butterfly populations in the Gulf Prairies and Marshes ecoregion in Willacy and Kenedy Counties, TX, USA. These weather events occurred during an ongoing study of effects of prescribed burning during summer or winter on butterfly populations. We tested effects of Category 1 Hurricane Hanna by comparing butterfly abundance in the month prior to and following the hurricane (July and August 2020). We tested effects of Winter Storm Uri by comparing butterfly abundance in the three months following the storm (March through May 2021) with abundance during the same period in the previous year (March through May 2020). We measured no effect of the Category 1 hurricane on butterfly populations overall and across all prescribed fire regimes. There was a significant reduction in butterfly abundance following the 2021 winter storm, and effects depended on prescribed fire regime. Our findings indicate that extremely cold temperatures in subtropical regions will likely have greater negative effects on butterfly populations than low-magnitude hurricanes. Implications for insect conservation: With extreme climate events (ECEs) predicted to increase in the future, measures should be taken to provide protection and refugia for butterflies, particularly from prolonged, uncharacteristically low temperatures. Protection includes maintaining undisturbed areas with accumulated plant matter, in preparation for these unpredictable events. [ABSTRACT FROM AUTHOR]

Abstract. Climate change is dramatically altering global precipitation patterns across terrestrial ecosystems, making it critically important that we understand both how and why plant species vary in their drought sensitivities. Andropogon gerardii and Schizachyrium scoparium , both C4 grasses, provide a model system for understanding the physiological mechanisms that determine how species of a single functional type can differ in drought responses, an issue remains a critical gap in our ability to model and predict the impacts of drought on grassland ecosystems. Despite its greater lability of foliar water content, previous experiments have demonstrated that S. scoparium maintains higher photosynthetic capacity during droughts. It is therefore likely that the ability of S. scoparium to withstand drought instead derives from a greater metabolic resistance to drought. Here, we tested the following hypotheses: (H1) A. gerardii is more vulnerable to drought than S. scoparium at both the population and organismal levels, (H2) A. gerardii is less stomatally flexible than S. scoparium , and (H3) A. gerardii is more metabolically limited than S. scoparium. Our results indicate that it is actually stomatal limitations of CO2 supply that limit A. gerardii photosynthesis during drought. Schizachyrium scoparium was more drought-resistant than A. gerardii based on long-term field data, organismal biomass production and physiological gas exchange measurements. While both S. scoparium and A. gerardii avoided metabolic limitation of photosynthesis, CO2 supply of A. gerardii was greatly reduced during late-stage drought stress. That two common, co-occurring C4 species possess such different responses to drought highlights the physiological variability inherent within plant functional groups and underscores the need for more studies of C4 drought tolerance. [ABSTRACT FROM AUTHOR]

Background. During the COVID-19 pandemic, public health approaches and diseasetransmission varied widely across Canadian regions. This may have led to different trajectories for moderate-to-vigorous intensity physical activity (MVPA) and screen time during this period. The purpose of this investigation was to describe age- and gender-specific regional trends in MVPA and screen time for Canadian youth (ages 12-17 years) and adults (ages 18+) from 2018 to 2021. Methods. Data was collected using the Canadian Community Health Survey, which includes representative data for 5 distinct regions: Atlantic Canada, Québec, Ontario, the Prairie Provinces, and British Columbia (BC). Participants aged 12+ in each region self-reported their total daily screen time, as well as MVPA in 5 domains: overall, recreational, school, occupational/household and active transportation. Results were compared for 2018 (pre-pandemic), January-March of 2020, September-December of 2020, and 2021 using repeated measures t -tests. Results. Among youth, all regions except for Atlantic Canada and BC experienced significant reductions in the proportion of youth meeting MVPA recommendations in the fall of 2020 (all p < 0.001), although these had returned to baseline for all regions except Ontario by 2021. Trends varied across regions among adults aged 18-64 years. In Québec, there was 7-percentage point reduction in the proportion of males meeting the MVPA recommendations in the fall of 2020 compared to 2018, while there was a 4-percentage point increase among females in 2021 (all p<0:05). In Ontario and the Prairie provinces, males saw a 4-percentage point decrease in activity recommendation adherence in 2021, when compared to 2018 (p<005). There were no other significant differences for any region when comparing the fall of 2020 or 2021 with 2018 (all p>0:05). Among adults aged 65+ years, significant increases in MVPA were observed in Atlantic Canada and the Prairies in the fall of 2020, and in Atlantic Canada, Québec and the Prairies in 2021 (all p < 0:05). With limited exceptions, self-reported screen time increased significantly across regions and age groups for both males and females (all p < 0.05). Conclusions. MVPA levels of Canadians during the COVID-19 pandemic varied both by region and age group. Self-reported MVPA of Canadian youth dropped in most regions in the fall of 2020, before returning to pre-pandemic levels in 2021. Activity levels of Canadians aged 18-64 years were relatively stable during the pandemic and increased for Canadians aged 65+ in most regions. Differences in trajectories across genders observed at the national level were often less apparent in individual regions. Recreational screen use increased across all regions, ages and genders with very few exceptions. These results highlight the differences and similarities in activity and screen time trajectories across the Canadian population and suggest the need for additional research to identify best practices for promoting healthy movement behaviours during future pandemics. [ABSTRACT FROM AUTHOR]

Copyright of Fire Ecology is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Fisher's fundamental theorem of natural selection (FTNS) can be used in a quantitative genetics framework to predict the rate of adaptation in populations. Here, we estimated the capacity for a wild population of the annual legume Chamaecrista fasciculata to adapt to future environments and compared predicted and realized rates of adaptation. We planted pedigreed seeds from one population into three prairie reconstructions along an east-to-west decreasing precipitation gradient. The FTNS predicted adaptation at all sites, but we found a response to selection that was smaller at the home and westernmost sites and maladaptive at the middle site because of changes in the selective environment between generations. However, mean fitness of the progeny generation at the home and westernmost sites exceeded population replacement, which suggests that the environment was sufficiently favorable to promote population persistence. More studies employing the FTNS are needed to clarify the degree to which predictions of the rate of adaptation are realized and its utility in the conservation of populations at risk of extinction from climate change. [ABSTRACT FROM AUTHOR]

French immersion (FI) programs are becoming increasingly culturally and linguistically diverse as a result of growing migration to Canada. In the present mixed-methods study, I explore the perspectives and ideologies of teachers, principals, and central office staff in eight school divisions in Saskatchewan, Manitoba, and Alberta with respect to refugee-background students in FI programs. Through the triangulation of survey responses (N=126) and interviews (N=40), I examine perspectives pertaining to four themes: 1) suitability of FI for refugee-background students; 2) language learning; 3) challenges facing refugee-background students; and 4) supports and resources in FI programs. Adopting the theoretical perspective of sociolinguistics for change, I discuss three underlying ideologies shaping the perspectives of FI educators across the Canadian Prairies: 1) English-first ideologies; 2) deficit ideologies; and 3) ideological tensions between inclusion and support. [ABSTRACT FROM AUTHOR]

Fire is a vital management tool for maintaining prairie ecosystems. Prescribed burns control invasive species, regulate succession, stimulate plant growth, and are a cheap and effective method for removing excess biomass; however, fire can also inadvertently cause wildlife mortality, placing land managers in a challenging situation. Turtles are especially at risk of mortality from fire because of their low mobility and population sensitivity to reductions in adult survival. We studied ornate box turtles (Terrapene ornata) at 3 sites in Illinois, USA, from 2019–2022 to determine the best predictors of above‐ground activity so land managers can conduct prescribed burns when turtles are underground. We used turtle shell temperature, air temperature, soil temperature, and precipitation data to develop a predictive model of above‐ground activity. The best model for predicting above‐ground activity included an interaction between day of year and current air temperature. Earlier in spring and later in fall, above‐ground activity is more likely at higher air temperatures compared to later in spring and earlier in fall when the same likelihood of above‐ground activity is predicted at lower air temperatures. In spring, we recommend burning in Illinois ornate box turtle habitat before 1 April when air temperature is <10°C and in fall after 1 November when air temperature is <15°C. Above these temperature thresholds, there is a >5% likelihood that turtles in northern populations are above ground. [ABSTRACT FROM AUTHOR]

In the midst of an ongoing biodiversity crisis, much research has focused on species losses and their impacts on ecosystem functioning. The functional consequences (ecosystem response) of shifts in communities are shaped not only by changes in species richness, but also by compositional shifts that result from species losses and gains. Species differ in their contribution to ecosystem functioning, so species identity underlies the consequences of species losses and gains on ecosystem functions. Such research is critical to better predict the impact of disturbances on communities and ecosystems. We used the "Community Assembly and the Functioning of Ecosystems" (CAFE) approach, a modification of the Price equation to understand the functional consequences and relative effects of richness and composition changes in small nonvolant mammal and dung beetle communities as a result of two common disturbances in North American prairie restorations, prescribed fire and the reintroduction of large grazing mammals. Previous research in this system has shown dung beetles are critically important decomposers, while small mammals modulate much energy in prairie food webs. We found that dung beetle communities were more responsive to bison reintroduction and prescribed fires than small nonvolant mammals. Dung beetle richness increased after bison reintroduction, with higher dung beetle community biomass resulting from changes in remaining species (context‐dependent component) rather than species turnover (richness components); prescribed fire caused a minor increase in dung beetle biomass for the same reason. For small mammals, bison reintroduction reduced energy transfer through the loss of species, while prescribed fire had little impact on either small mammal richness or energy transfer. The CAFE approach demonstrates how bison reintroduction controls small nonvolant mammal communities by increasing prairie food web complexity, and increases dung beetle populations with possible benefits for soil health through dung mineralization and soil bioturbation. Prescribed fires, however, have little effect on small mammals and dung beetles, suggesting a resilience to fire. These findings illustrate the key role of re‐establishing historical disturbance regimes when restoring endangered prairie ecosystems and their ecological function. [ABSTRACT FROM AUTHOR]

Climate change is increasing the frequency and intensity of extreme events like drought and flooding, which threaten to amplify other global change drivers such as species invasion. We investigate the effect of wet and dry extreme precipitation regimes on invasive species' abundances in northern tallgrass prairies. Because soil moisture is a key determinant of prairie composition, theory and evidence suggest drought conditions will hinder invasion, whereas wetter conditions will enhance invasion. To test this hypothesis, we explored the effect of precipitation on invasive plant species abundance from 2010 to 2019 in 25 managed prairies using observations from 267 transects comprising 6675 plots throughout western Minnesota, USA. We estimated how increases in the number of extremely wet or dry months in a year altered overall invasive species abundance and the abundance of the highly invasive grasses Poa pratensis and Bromus inermis. We found that a greater occurrence of abnormally wet months increased invasive species abundance but found mixed evidence that abnormally dry conditions hindered invasion. Further, more moderately wet and dry months reduced native grass abundance. Together, these results suggest that more frequent extremely wet months may intensify invasive dominance and that dry months may not counterbalance these trends. Given the considerable uncertainty still surrounding the interactive effects of climate change and invasion on native plant communities, this research represents an important step toward quantifying the complex influence of precipitation extremes on invasion dynamics in managed ecosystems of critical conservation concern. [ABSTRACT FROM AUTHOR]

The hearing abilities of mammals are impacted by factors such as social cues, habitat, and physical characteristics. Despite being used commonly to study social behaviors, hearing of the monogamous prairie vole (Microtus ochrogaster) has never been characterized. In this study, anatomical features are measured and auditory brainstem responses (ABRs) are used to measure auditory capabilities of prairie voles, characterizing monaural and binaural hearing and hearing range. Sexually naive male and female voles were measured to characterize differences due to sex. It was found that prairie voles show a hearing range with greatest sensitivity between 8 and 32 kHz, binaural hearing across interaural time difference ranges appropriate for their head sizes. No differences are shown between the sexes in binaural hearing or hearing range (except at 1 kHz), however, female voles have increased amplitude of peripheral ABR waves I and II and longer latency of waves III and IV compared to males. The results confirm that prairie voles have a broad hearing range, binaural hearing consistent with rodents of similar size, and differences in amplitudes and thresholds of monaural physiological measures between the sexes. These data further highlight the necessity to understand sex-specific differences in neural processing that may underly variability in responses between sexes. [ABSTRACT FROM AUTHOR]

The article focuses on the return of conferences to the Prairies, highlighting the 49th Annual Conference of the Society for the Study of Architecture in Canada (SSAC) in Winnipeg and the Western Canadian History Conference (WCHC) in Saskatoon. Topics include the themes of the conferences, the organizations hosting them, and the significance of these academic gatherings for scholarly exchange and exploration of regional histories.

Intensive agriculture has led to widespread losses of native grasslands. Restoration projects are trying to reestablish native communities. However, the poor quality and altered food webs of former agricultural soils act as barriers to establishing diverse plant communities. Soil amendments such as biochar have been used to improve soil quality and increase crop yield, but little research has been on biochar in restoration settings. Eastern Washington University is attempting to restore a former wheat field to native Palouse prairie vegetation. In this study, we compared (1) soil abiotic properties and food webs between Palouse prairie remnants and Eastern Washington University's (EWU) restoration site and (2) tested whether biochar can move soil conditions at EWU's restoration site closer to those of remnant sites. We compared soils from three Palouse prairie remnants and EWU's restoration site, and compared soils at the restoration site that were treated with different levels of biochar. Soil nematodes were extracted and sorted to functional groups as an assay of the structure and functional diversity of the soil food web. The soil at EWU's restoration site had significantly lower nematode abundance, pH, and organic matter compared to prairie remnants. In addition, nematode abundance and pH increased significantly at the EWU site with the addition of biochar, both increasing to conditions similar to what is found at the prairie remnant sites. These results suggest biochar can improve some soil conditions in former agricultural lands even prior to native plant restoration. [ABSTRACT FROM AUTHOR]

Knowing glass beads as active agents – as beings – proffers forms of analysis untethered from linear temporality and immersed in story. Analytical frameworks steeped in Western philosophical traditions dictate limited understandings of art made by Indigenous peoples within the study of art histories, and as displayed and collected by museums and galleries. Despite museological conventions that reproduce entrenched processes of objectification and linear classifications, appreciating Indigenous beadwork through relational and dialogical epistemologies has gained traction within the study of Indigenous arts in Canada. In support of future generations of Indigenous makers in the prairie region, this analysis upends conventional colonial structures of knowledge entrenched in institutions. [ABSTRACT FROM AUTHOR]

A comparison was made of the supercooling points (SCPs) of questing Dermacentor variabilis adults from two populations located ca. 800 km apart on the Canadian prairies. This is also the first study to examine whether there are seasonal fluctuations in the SCP of questing D. variabilis adults. The SCPs of adult ticks from Lizard Lake Community Pasture, a recently established population in west-central Saskatchewan, varied over spring and summer, with the median SCP warming over time. In addition, the SCPs of ticks from Lizard Lake Community Pasture were significantly higher than those of adult ticks collected from Sandy Hook in Manitoba, a population that has been established for decades. The off-host survival of adults from Sandy Hook between summer and spring has been shown previously to be significantly greater than that of adults from Lizard Lake Community Pasture. The findings of the present study suggest that there may be geographical variation in the SCPs of D. variabilis adults which may be associated with differences in overwinter survival. The relatively low SCPs of questing D. variabilis adults, and the ability of some adults to survive off-host during winter, may be factors contributing to the range expansion of this tick species in Canada. [ABSTRACT FROM AUTHOR]

Soil organic carbon (SOC) sequestration assessment requires accurate and effective tools for measuring baseline SOC stocks. An emerging technique for estimating baseline SOC stocks is predictive soil mapping (PSM). A key challenge for PSM is determining sampling density requirements, specifically, determining the economically optimal number of samples for predictive soil mapping for SOC stocks. In an attempt to answer this question, data were used from 3861 soil organic carbon samples collected as part of routine agronomic soil testing from a 4702 ha farming operation in Saskatchewan, Canada. A predictive soil map was built using all the soil data to calculate the total carbon stock for the entire study area. The dataset was then subset using conditioned Latin hypercube sampling (cLHS), both conventional and stratified by slope position, to determine the total carbon stocks with the following sampling densities (points per ha): 0.01, 0.05, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, and 0.8. A nonlinear error function was then fit to the data, and the optimal number of samples was determined based on the number of samples that minimized soil data costs and the value of the soil carbon stock prediction error. The stratified cLHS required fewer samples to achieve the same level of accuracy compared to conventional cLHS, and the optimal number of samples was more sensitive to carbon price than sampling costs. Overall, the optimal sampling density ranged from 0.025 to 0.075 samples per hectare. [ABSTRACT FROM AUTHOR]

Waterbirds are one of the most conspicuous components of wetlands, and are frequently proposed as bioindicators of the state of these ecosystems. However, the mobility of waterbirds allows them to make complementary use of resources found beyond the limits of permanent wetlands. Therefore, understanding the relationships between the conditions of waterbodies and waterbird populations, requires a landscape- level approach. The objective of this study was to assess the complementary use of a permanent wetland (estuary) and its surrounding landscape by a waterbird community in Central Chile. During three years, we seasonally censused the waterbird populations present at the estuary of the Carampangue river (128 ha) and, in addition, estimated the abundance of the same species in the surrounding landscape (3,952 ha) through 71 point-count stations. A total of 69 species of birds were recorded in the estuary, and 51 species in the surrounding landscape. The strong negative temporal correlations between the populations at the estuary and landscape are indirect evidence for a complementary use of the two systems, mostly driven by seasonal flooding in agricultural land. The seasonal use of landscape resources was more marked among Anseriformes and grebes. Using generalized additive models (GAM), we observed that the percentage of flooded area and non-flooded prairies were among the most important predictors of landscape use by most species. Our results reinforce the need to expand the assessment of waterbird populations beyond waterbodies, including neighboring habitats of potential usefulness for this group of birds.

The article discusses the fourth Ecology of Soil Microorganisms (ESM4) conference held in Prague, Czech Republic in June 2022. The conference brought together 200 scientists to discuss the role of microorganisms in ecosystem processes, particularly in the context of global change and future climatic conditions. The article highlights the importance of studying microbial ecology in agricultural soils, grasslands, forests, peatlands, and alpine treeline ecosystems. It also explores various interactions between microorganisms, such as symbiosis and antagonism. The article concludes by emphasizing the potential of microbial ecology to enhance our understanding of microbiomes and contribute to more sustainable ecosystem management. [Extracted from the article]

Ecological studies investigating the effects of artificial light at night (ALAN) have primarily focused on single or a few species, and seldom on community-level dynamics. As ALAN is a potential cause of insect and biodiversity declines, community-level perspectives are essential. We empirically tested the hypothesis that moth species differentially respond to ALAN and that these responses can cause shifts in community composition. We sampled moths from prairie fragments in Colorado, USA. We tested whether local light sources, sky glow, site area and/or vegetation affected moth community diversity. We found that increased sky glow decreased moth abundance and species richness and shifted community composition. Increased sky glow shifted moth community composition when light and bait traps were combined; notably this result appears to be driven entirely by moths sampled at bait traps, which is an unbiased sampling technique. Our results show that ALAN has significant effects on moth communities and that local light sources have contrasting effects on moth community composition compared to sky glow. It is imperative that we better understand the contrasting effects of types of ALAN to comprehend the overall impacts of light pollution on biodiversity declines. This article is part of the theme issue 'Light pollution in complex ecological systems'. [ABSTRACT FROM AUTHOR]

Many carnivore populations have experienced substantial declines and are at increased risk of extinction, mainly due to negative interactions with humans and biological traits that make them susceptible to habitat loss and fragmentation, often driven by agricultural expansion. Carnivore community richness is likely influenced by many direct and indirect factors, though it is unclear how carnivore communities are structured in prairie landscapes that are considered one of the most imperiled ecosystems worldwide. Our goal was to identify landscape-scale effects driving carnivore community richness in a contemporary agro-prairie ecosystem. We used 3 years of presence data (2018–2020) from camera-trap sites (n = 381) distributed across western Kansas, United States and developed a structural equation model (SEM) to test a priori hypotheses explaining carnivore richness. Measures of water availability, native prairie, and agriculture—as well as sampling effort (i.e. days cameras were active)—were all positively associated with carnivore richness. Additionally, our index of rabbit abundances at sites had a direct positive effect on our measure of carnivore richness. Our SEM explained 42% of the variance in carnivore richness (χ2 = 8.76, d.f. = 21, P = 0.99) in this human-dominated landscape. Our results suggest that carnivore communities in agro-prairie landscapes are structured through multiple direct and indirect landscape-scale pathways. Contemporary agro-prairie mosaics may act as filters for the agricultural tolerance of carnivores, with species more vulnerable to native prairie loss becoming locally extirpated. [ABSTRACT FROM AUTHOR]

The expansion of woody species from their historical ranges into grasslands is a global problem. Understanding the mechanisms that enable species to successfully establish and then re‐encroach following their removal is critical to effectively managing problem species. Legacy effects are a mechanism that could be critical to the reestablishment of woody encroachers following their removal. Legacy effects occur when a species alters the biotic and abiotic environment in a way that affects communities that establish subsequently. In this study, we assess whether the eastern redcedar (Juniperus virginiana), a North American woody encroacher, generates legacy effects that affect communities that establish following removal of this species from an experimental grass community. We conducted a series of experiments to evaluate the effects of J. virginiana, roots on the germination and growth of grasses and to determine if the effects of root‐addition treatments were derived from a microbial or allelopathic origin. Aqueous extracts of J. virginiana roots were found to inhibit the germination of grasses. We found escalating suppression of overall community biomass and the biomass of each individual species with increasing root treatments. Finally, we determined the origin of the observed suppressive effect is unlikely to be of microbial origin. Synthesis: Our results suggest that J. virginiana exudes an allelochemical into soils that inhibits the growth of certain grasses and thus has the potential to have legacy effects on future occupants. We suggest that the inhibition of the development of grasses in areas where J. virginiana has been removed is a mechanism that may favor the reestablishment of J. virginiana. Our results indicate the legacy effects of J. virginiana must be considered when conducting removal and restoration of J. virginiana infested lands. [ABSTRACT FROM AUTHOR]

The ancient hay meadows at Wakehurst, Kew's wild botanic garden, are described, and many of the species which go to make up these High Weald grasslands are illustrated. Native Sussex hay meadows and North American prairie grasslands are compared. [ABSTRACT FROM AUTHOR]