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For animals that produce species‐specific audible sounds, environmental recordings combined with automated acoustic monitoring software (passive acoustic monitoring [PAM]) may be an effective monitoring tool because it allows audio data from many, widely distributed autonomous recording units (ARUs) to be processed in a relatively short period of time. Males of many insect species produce loud, species‐specific mating songs, yet acoustic insects have received less attention from PAM relative to vertebrates.We evaluated the use of PAM to monitor, Roeseliana roeselii (Orthoptera, Tettigoniidae), an acoustic insect that has expanded its range to Alberta, Canada, far outside its naturalized North American range. We analysed environmental recordings from ARUs: (1) at two control sites known to be occupied by R. roeselii and (2) across Alberta established by the Alberta Biodiversity Monitoring Institute (ABMI) to search for new populations.PAM successfully detected R. roeselii at the two control sites, but not at any of the 73 ABMI sites that we analysed. Despite the failure to detect new locations of R. roeselii, our analysis of ABMI environmental recordings detected several other species of acoustic insects, including Orchelimum gladiator, Gryllus sp. and Allonemobius spp.Our results add to the growing body of work showing the feasibility of using PAM for acoustic insects. We make suggestions for how to maximize the effectiveness of this monitoring tool for the conservation and management of singing insects in North America. [ABSTRACT FROM AUTHOR]

Parent-offspring conflicts arise through the competing efforts of the parents (to optimize their reproductive success) and the offspring (to secure maximum resources for themselves to enhance survival). Competition among siblings in a brood plays a key role in each nestling's relative fitness, particularly in avian species that hatch asynchronously. Previously published research has shown that the first-hatched nestling secures the most food, often at an energetic cost to its siblings. However, few researchers have simultaneously investigated competition and parental allocation behaviors to determine their effects on food distribution among raptor nestlings. We found that Ferruginous Hawk (Buteo regalis) parents delivered the same number of prey to nests, regardless of brood size. Contrary to our expectations, all nestlings consumed a similar amount of food within individual feeding events. Importantly, neither nestling competition nor parental allocation was the dominant process responsible for equal food distribution. Instead, the first-hatched and second-hatched nestling gained more food by competition, and the third-hatched nestling gained more food through parental allocation. Although each nestling attempted to optimize its food consumption relative to its siblings, resulting in unequal competitive outcomes, parents altered their allocation behavior to offset sibling competition. Ultimately parents provided the last-hatched nestling with more food, and thereby controlled food distribution to maximize their reproductive output. Future work should explore the role of nestling competition and parental allocation on food distribution using supplementation at nests when prey abundance in the environment is low. [ABSTRACT FROM AUTHOR]

Geographic variation in song characteristics within songbird species has the potential to reveal some of the complex interactions between ecology and behavior. The Connecticut Warbler (Oporornis agilis) is an uncommon and little studied Neotropical migratory wood warbler that breeds across the southern boreal forest in North America. The song of the Connecticut Warbler has remained poorly described and, prior to our study, no detailed spectrographic analysis exists. We document 20 distinct song variants in this species, based on differences in the structure and sequence of notes within repeated phrases, from across the breeding range. One song type, distributed across the entire breeding range, represented 36% of our samples. Preliminary evidence suggests a lack of geographic structure and no evidence of dialects or regiolects in the song types of this species. Our results highlight a unique distribution in song types within the Oporornis–Geothlypis complex, providing a baseline for future studies of geographic variation in this, and related, species. [ABSTRACT FROM AUTHOR]

Habitat fragmentation occurs when continuous habitat gets broken up as a result of ecosystem change. While commonly studied in terrestrial ecosystems, Arctic sea ice ecosystems also experience fragmentation, but are rarely studied in this context. Most fragmentation analyses are conducted using patch‐based metrics, which are potentially less suitable for sea ice that has gradual changes between sea ice cover, than distinct "long‐term" patches. Using an integrated step selection analysis, we compared the descriptive power of a patch‐based metric to a more novel metric, the variation in local spatial autocorrelation over time. We used satellite telemetry data from 39 adult female polar bears (Ursus maritimus) in Hudson Bay to examine their sea ice habitat using Advanced Microwave Scanning Radiometer 2 data during sea ice breakup in May through July from 2013–2018. Spatial autocorrelation resulted in better model fits across 64% of individuals, although both metrics were more effective in describing movement patterns than habitat selection. Variation in local spatial autocorrelation allows for the visualization of sea ice habitat at complex spatial and temporal scales, condensing a targeted time period of habitat that would otherwise have to be analyzed daily. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the effects of 60 min daily, short-term (STHA) and medium-term (MTHA) isothermic heat acclimation (HA) on the physiological and perceptual responses to exercise heat stress.Methods: Sixteen, ultra-endurance runners (female = 3) visited the laboratory on 13 occasions. A 45 min sub-maximal (40% Wmax) cycling heat stress test (HST) was completed in the heat (40 °C, 50% relative humidity) on the first (HSTPRE), seventh (HSTSTHA) and thirteenth (HSTMTHA) visit. Participants completed 5 consecutive days of a 60 min isothermic HA protocol (target Tre 38.5 °C) between HSTPRE and HSTSTHA and 5 more between HSTSTHA and HSTMTHA. Heart rate (HR), rectal (Tre), skin (Tsk) and mean body temperature (Tbody), perceived exertion (RPE), thermal comfort (TC) and sensation (TS) were recorded every 5 min. During HSTs, cortisol was measured pre and post and expired air was collected at 15, 30 and 45 min.Results: At rest, Tre and Tbody were lower in HSTSTHA and HSTMTHA compared to HSTPRE, but resting HR was not different between trials. Mean exercising Tre, Tsk, Tbody, and HR were lower in both HSTSTHA and HSTMTHA compared to HSTPRE. There were no differences between HSTSTHA and HSTMTHA. Perceptual measurements were lowered by HA and further reduced during HSTMTHA.Conclusion: A 60 min a day isothermic STHA was successful at reducing physiological and perceptual strain experienced when exercising in the heat; however, MTHA offered a more complete adaptation. [ABSTRACT FROM AUTHOR]

Automated recognition is increasingly used to extract information about species vocalizations from audio recordings. During processing, recognizers calculate the probability of correct classification ("score") for each acoustic signal assessed. Our goal was to investigate the implications of recognizer score for ecological research and monitoring. We trained four recognizers with clips of Common Nighthawk (Chordeiles minor) calls recorded at different distances: near, midrange, far, and mixed distances. We found distance explained 49% and 41% of the variation in score for the near and mixed-distance recognizers, but only 3% and 6% of the variation for the midrange and far recognizers. We calculated detection functions for each of the recognizers at various score thresholds and found that the detection function for the near and mixed-distance recognizers satisfied the assumptions of density estimation for most score thresholds, while the detection function for the midrange and far recognizers did not. The detection functions also showed that score threshold choice is a decision about sampling area, not just about the balance between recall and precision. Overall, we showed that training recognizers with 'high-quality' clips that were recorded at close range will improve the utility of the data without affecting how many true positives the recognizer detects. [ABSTRACT FROM AUTHOR]

Aim: Most large‐scale species distribution models assume spatially constant habitat selection throughout a species' geographic range. However, there is evidence this assumption may not be valid for a number of boreal bird species, which could lead to biased predictions of density and distribution in range‐wide models. Our goal was to test for and quantify differential habitat selection (DHS) in songbirds among regions of the Canadian boreal forest. Location: Northern Alberta, western Ontario and southern Quebec, Canada. Methods: We used hierarchical analysis of covariance models with region‐specific parameter estimates to test for differential selection of forest attributes among three regions for six boreal bird species. We used the results of these models to quantify intraspecific niche overlap between regions and compared posterior predictive accuracy to models that did not account for DHS. Results: We found a generally large standardized effect size (median effect size = 1.674) of region on selection of specific habitat variables for all six species, although there was high variability among species, variables and regional comparisons. The proportion of niche overlap between regions was generally low (mean overlap = 0.309 for all pairwise comparisons), with no spatial pattern to the overlap. Models accounting for DHS had significantly higher posterior predictive accuracy according to the Watanabe–Akaike information criterion. Main Conclusions: We found strong evidence for DHS among regions for six boreal songbird species in individual habitat attributes and overall niche space. The higher predictive accuracy of our DHS models suggests that failure to account for spatial variability in habitat selection can lead to biased estimates of density and spatial distribution. Models that did not account for DHS overestimated density relative to DHS models. We conclude that large‐scale species distribution models should account for regional variation in habitat selection in order to obtain accurate estimates of population size and distribution. [ABSTRACT FROM AUTHOR]

The activation and functionalization of C−F bonds has garnered significant attention in the scientific community as a strategy to mitigate toxicity and environmental concerns, as well as provide new pathways to agro‐ and pharmaceutical chemicals and materials. Although several transition‐metal‐based systems have been developed for this transformation, the use of main‐group compounds remains less explored. In recent years, several strategies for C−F bond activation have focused on the use of phosphorus‐based reagents. In this Minireview, an overview of strategies is provided that exploits PV and PIII‐based Lewis acids as well as PIII Lewis bases in frustrated Lewis pair (FLP) protocols for hydrodefluorination, C−C couplings and C−F derivatizations. [ABSTRACT FROM AUTHOR]

Background: Intracranial and intraspinal tumours are the most numerous solid tumours in children. Some recently defined subtypes are relatively frequent in childhood. Many cancer registries routinely ascertain CNS tumours of all behaviours, while others only cover malignant neoplasms. Some behaviour codes have changed between revisions of the International Classification of Diseases for Oncology, including pilocytic astrocytoma, downgraded to uncertain behaviour in ICD-O-3.Methods: We used data from the population-based National Registry of Childhood Tumours, which routinely included non-malignant CNS tumours, to document the occurrence of CNS tumours among children aged < 15 years in Great Britain during 2001-2010 and to document the descriptive epidemiology of childhood CNS tumours over the 40-year period 1971-2010, during which several new entities were accommodated in successive editions of the WHO Classification and revisions of ICD-O. Eligible cases were all those with a diagnosis included in Groups III (CNS tumours) and Xa (CNS germ-cell tumours) of the International Classification of Childhood Cancer, Third Edition. The population at risk was derived from annual mid-year estimates by sex and single year of age compiled by the Office for National Statistics and its predecessors. Incidence rates were calculated for age groups 0, 1-4, 5-9 and 10-14 years, and age-standardised rates were calculated using the weights of the world standard population.Results: Age-standardised incidence in 2001-10 was 40.1 per million. Astrocytomas accounted for 41%, embryonal tumours for 17%, other gliomas for 10%, ependymomas for 7%, rarer subtypes for 20% and unspecified tumours for 5%. Incidence of tumours classified as malignant and non-malignant by ICD-O-3 increased by 30 and 137% respectively between 1971-75 and 2006-10.Conclusions: Total incidence was similar to that in other large western countries. Deficits of some, predominantly low-grade, tumours or differences in their age distribution compared with the United States and Nordic countries are compatible with delayed diagnosis. Complete registration regardless of tumour behaviour is essential for assessing burden of disease and changes over time. This is particularly important for pilocytic astrocytoma, because of its recent downgrading to non-malignant and time trends in the proportion of astrocytomas with specified subtype. [ABSTRACT FROM AUTHOR]

The water/base intolerance of the previously reported electrophilic phosphonium cations has been overcome by replacing the labile electron-withdrawing groups generally attached to phosphorus (e.g.–F, –OAr, –CF3) with methyl groups. Tri-phosphorus(v) tricationic species, accessible in one-pot from commercially available materials, are air and water/base tolerant, yet are sufficiently Lewis acidic for catalysis. [ABSTRACT FROM AUTHOR]

The electrophilic pyridinium-substituted phenoxy-phosphonium dicationic salt [(PhO)P(2-(N-Mepy))Ph2][B(C6F5)4]2, is shown to be an effective catalyst for the double hydroarylation of alkynes with diarylamines to afford a series of 9-methyl-9-aryl-9,10-dihydroacridine and 9,10-dimethyl-9-aryl-9,10-dihydroacridine derivatives. [ABSTRACT FROM AUTHOR]

The Canada Warbler (Cardellina canadensis) is a threatened species in Canada due to an annual decline of ∼3% over the last 50 yr. Some studies suggest that Canada Warblers prefer old-growth forest and that forestry practices may reduce suitable habitat, while other research indicates that the species will also use harvested areas. Differences in scale between habitat use studies and behavioral phenomena such as conspecific attraction may explain this discrepancy. We examined how Canada Warblers responded to forestry and conspecifics in Alberta, Canada. We used point counts, burst sampling, and behavioral observations to determine how the density, home range placement (second-order habitat use), within-home-range space use (third-order habitat use), and probability of pairing and fledging young of male Canada Warblers were influenced by postharvest conditions (i.e. amount, age [≤ 30 yr postharvest], and retention of unharvested fragments) and conspecifics. Male density was 86% lower in postharvest than in unharvested stands. However, males were 16.6 times more likely to place their home ranges in postharvest stands within 100 m of unharvested stands than 300 m into harvested areas, and 3 times more likely to place their home ranges 100 m from conspecifics than 300 m away. Within-home-range space use was 1.1 times higher 50 m from conspecifics than 350 m away, and 2.6 times higher 300 m from an edge than 100 m away. Use of harvested areas did not affect reproductive activity, but the probability of pairing was 1.8 times higher for males in low-density (2 males per 17.3 ha) than in high-density areas (7 males per 17.3 ha). Our results suggest that Canada Warbler use of postharvest stands on the boreal breeding grounds is more heavily influenced by conspecifics than by postharvest conditions. Because Canada Warbler territories are clustered, conservation efforts should prioritize the retention of large tracts of unharvested forest near occupied breeding sites. [ABSTRACT FROM AUTHOR]

The objectives of this study were to describe and evaluate potential drivers of genetic structure in Canadian breeding populations of the Ovenbird, Seiurus aurocapilla. We performed genetic analyses on feather samples of individuals from six study sites using nuclear microsatellites. We also assessed species identity and population genetic structure of quill mites (Acariformes, Syringophilidae). For male Ovenbirds breeding in three study sites, we collected light-level geolocator data to document migratory paths and identify the wintering grounds. We also generated paleohindcast projections from bioclimatic models of Ovenbird distribution to identify potential refugia during the last glacial maximum ( LGM, 21,000 years before present) as a factor explaining population genetic structure. Birds breeding in the Cypress Hills (Alberta/Saskatchewan) may be considered a distinct genetic unit, but there was no evidence for genetic differentiation among any other populations. We found relatively strong migratory connectivity in both western and eastern populations, but some evidence of mixing among populations on the wintering grounds. There was also little genetic variation among syringophilid mites from the different Ovenbird populations. These results are consistent with paleohindcast distribution predictions derived from two different global climate models indicating a continuous single LGM refugium, with the possibility of two refugia. Our results suggest that Ovenbird populations breeding in boreal and hemiboreal regions are panmictic, whereas the population breeding in Cypress Hills should be considered a distinct management unit. [ABSTRACT FROM AUTHOR]

Point counts are one of the most common ways of collecting data to determine the relative abundance of birds. Many studies and monitoring programs, including the North American Breeding Bird Survey, use relative differences in counts of birds to assess changes in abundance over time and space. Many factors influence whether relative differences in counts of birds between various environmental conditions are reflective of actual differences in bird density. A major assumption of relative abundance is that birds with different song frequencies and amplitudes are heard at the same distances in different environmental conditions. We compared sound transmission in forest habitats and along low-use forestry roads, and calculated detection radius for different species to test the assumption that differences in bird counts between forest interior and roadside locations reflect actual differences in bird abundance. A playback-recording experiment was used to broadcast sounds through forest interior, along a forest edge, and down forestry roads in conifer and deciduous forests to determine whether sound propagation differed across environments. Sound attenuated significantly faster in forests than along roads or forest edges. Similarly, the distance at which bird songs could be detected was significantly shorter in forest than along the road or forest edge for 20 of 25 species. We found the area surveyed to be up to twice as large on road compared to within forests, which suggests that roadside surveys might inflate avian density estimates in comparison to off-road counts. Local atmospheric conditions also influenced detection probability, but the magnitude of the effect was weaker than the land-cover effect. Major differences in detection between roads and interior forest suggest that comparisons of surveys conducted along roadsides and in forest areas should be done carefully if the goal is to make direct comparisons of abundance. [ABSTRACT FROM AUTHOR]

Point counts are one of the most common ways of collecting data to determine the relative abundance of birds. Many studies and monitoring programs, including the North American Breeding Bird Survey, use relative differences in counts of birds to assess changes in abundance over time and space. Many factors influence whether relative differences in counts of birds between various environmental conditions are reflective of actual differences in bird density. A major assumption of relative abundance is that birds with different song frequencies and amplitudes are heard at the same distances in different environmental conditions. We compared sound transmission in forest habitats and along low-use forestry roads, and calculated detection radius for different species to test the assumption that differences in bird counts between forest interior and roadside locations reflect actual differences in bird abundance. A playback–recording experiment was used to broadcast sounds through forest interior, along a forest edge, and down forestry roads in conifer and deciduous forests to determine whether sound propagation differed across environments. Sound attenuated significantly faster in forests than along roads or forest edges. Similarly, the distance at which bird songs could be detected was significantly shorter in forest than along the road or forest edge for 20 of 25 species. We found the area surveyed to be up to twice as large on road compared to within forests, which suggests that roadside surveys might inflate avian density estimates in comparison to off-road counts. Local atmospheric conditions also influenced detection probability, but the magnitude of the effect was weaker than the land-cover effect. Major differences in detection between roads and interior forest suggest that comparisons of surveys conducted along roadsides and in forest areas should be done carefully if the goal is to make direct comparisons of abundance. [ABSTRACT FROM AUTHOR]

Songbirds have a high nest failure rate, with most failed nest attempts caused by predation. While songbird behavior before and during predation events has been documented, post-predation behavior has not. We observed post-predation behavior from 36 complete predation events (all fledglings or eggs taken by predator resulting in an empty nest) of nine songbird species by using video monitoring. We examined the time for the parent to abandon the empty nest and the number of return visits the parent made before abandoning the empty nest. Increased nestling age at the time of predation resulted in parents abandoning the nest sooner and making fewer return visits to the nest post-predation. There was weak evidence that parental behavior after predation differed based on the species of predator that destroyed the nest. Other post-predation behaviors included parents returning to eat eggshells, incubation of empty nests, and food provisioning. The extended time required to leave a nest after it has failed suggests birds have a compulsion that needs to be 'switched off' prior to abandoning a nest. Why birds engage in such behaviors post-predation is unclear but indicates a lack of selection pressure to evolve an 'immediate response' to predation. Presumably, delays in subsequent re-nesting attempts caused by such behaviors are minor but this hypothesis warrants further research. [ABSTRACT FROM AUTHOR]

Bird-window collisions at houses have been identified as a significant source of mortality for North American birds, but which types of houses and windows are most problematic remains poorly understood. We assessed how neighborhood type, yard conditions, house attributes, and window type influenced collision rates. Data were collected from citizen scientists across Alberta, Canada, who surveyed their houses daily. In relation to the best-fitting model, the yard model explained 58.1% of the explained deviance, the neighborhood model 45.6%, and the house model 42.6%. The factors that had the largest effect for predicting collision risk included season and whether the house was in a rural or an urban area (rural areas in the fall had a 6.0× higher collision risk than urban areas in the winter), the height of vegetation in the front yard of the house (trees >2 stories high increased collision risk by 3.6× compared to houses with no trees), and the presence of a bird feeder (which increased collision risk by 1.7×). This suggests that multiple factors affect collision rates and that the suitability of a yard as bird habitat is likely a key driver. Given that few homeowners are likely to take an approach that reduces the number of birds in their yards, future focus needs to be given to bird-friendly urban design and developing the most effective window deterrents so that collisions can be reduced and birds enjoyed in urban environments. [ABSTRACT FROM AUTHOR]

Using commercially available 2-pyridyldiphenylphosphine (o-NC5H4)PPh2, a family of electrophilic phosphonium cations [(o-NC5H4)PFPh2]+ (2) and dications [(o-MeNC5H4)PRPh2]2+ (R = F (4); Me (5)) were prepared. The Lewis acidity of these pyridinium–phosphonium dications was probed in Friedel–Crafts dimerization, hydrodefluorination, hydrosilylation, dehydrocoupling and hydrodeoxygenation reactions. The influence of the counterion on the catalytic activity of the electrophilic phosphonium cations is also discussed. [ABSTRACT FROM AUTHOR]

Part of the renaissance in main group chemistry has been a result of the focus on reactivity. This has led to the development of applications in stoichiometric reactivity and catalysis. In this tutorial review, we focus attention on the role of phosphorus-based Lewis acids in such advances. While early literature recognizes the role of P(iii) and P(v) electrophiles in coordination chemistry, it has generally been more recent studies that have focused on applications of this Lewis acidity. Applications of these novel P-based Lewis acids in stoichiometric reactivity, Lewis acid catalysis and frustrated Lewis pair (FLP) reactivity are reviewed. These advances demonstrate that P-based Lewis acids are a powerful tool for further developments in metal-free catalysis. [ABSTRACT FROM AUTHOR]

Four perfluoroalkyl cobalt(lll) fluoride complexes have been synthesized and characterized by elemental analysis, multinuclear NMR spectroscopy, X-ray crystallography, and powder X-ray diffraction. The remarkable cobalt fluoride 19F NMR chemical shifts (–716 to –759 ppm) were studied computationally, and the contributing paramagnetic and diamagnetic factors were extracted. Additionally, the complexes were shown to be active in the catalytic fluorination ofp-toluoyl chloride. Furthermore, two examples of cobalt(III) bis(perfluoroalkyl)complexes were synthesized and their reactivity studied. Interestingly, abstraction of a fluoride ion from these complexes led to selective formation of cobalt difluorocarbene complexes derived from the trifluoromethyl ligand. These electrophilic difluorocarbenes were shown to undergo insertion into the remaining perfluoroalkyl fragment, demonstrating the elongation of a perfluoroalkyl chain arising from a difluorocarbene insertion on a cobalt metal center. The reactions of both the fluoride and bis(perfluoroalkyl) complexes provide insight into the potential catalytic applications of these model systems to form small fluorinated molecules as well as fluoropolymers. [ABSTRACT FROM AUTHOR]

Given the substantial impacts of non-native species on invaded systems, an understanding of the rates and spatial patterns of invasive spread is critical. Spread may vary across spatial scales, with dispersal of invasive species occurring both via diffusive spread at local sites and long-distance jump dispersal at larger scales. Research on earthworm invasions in North American forests has focused on patterns of spread across landscapes, with less examination of spread at local sites. We sampled the exotic earthworm Dendrobaena octaedra (Savigny, 1826) on 500 m × 500 m grids at three sites in the boreal forest of northeastern Alberta in 2006 and again in 2012-2013 to examine distributional changes over time. Earthworms spread farther from roads (the presumed site of initial introduction) over time, and spatial patterns at our sites suggest transport by vehicles and waterways are key vectors of dispersal at the local level. Spread was estimated to be occurring at a rate of at least 17.9 m/year. Our study indicates that both diffusive spread and jump dispersal of earthworms can be important at local scales and that local diffusive spread may be substantially higher than previously estimated. [ABSTRACT FROM AUTHOR]

Aim Species and ecosystems may be unable to keep pace with rapid climate change projected for the 21st century. We evaluated an underexplored dimension of the mismatch between climate and biota: limitations to forest growth and succession affecting habitat suitability. Our objective was to inform continental-scale conservation for boreal songbirds under disequilibria between climate, vegetation and fauna. Location Boreal and southern arctic ecoregions of North America. Methods We used forest inventory and avian survey data to classify 53 species by seral-stage affinity and applied these to generate alternative projections of changes in species' core habitat distributions based on different vegetation lag-time assumptions. We used our seral stage-modified refugia approach and the Zonation algorithm to identify multispecies boreal conservation priorities over the 21st century. We evaluated the sensitivity of land rankings to seral-stage affinity and species' weights and assessed the conservation value of the existing protected areas network compared to Zonation results. Results End-of-century projected changes in songbird distribution were reduced by up to 169% when vegetation lags were considered. Zonation land rankings based on unconstrained climate projections were concentrated at high latitudes, whereas those based on strict and modified refugia scenarios were concentrated in coastal and high-elevation areas, as well as biome transition zones, which were fairly consistent over time and species weights. The existing protected areas network covering 14% of the study area was estimated to conserve 12-14% of baseline avian biodiversity across time periods and scenarios, compared to 16-25% for top-ranked Zonation areas. Main conclusions For some boreal songbirds, limits to forest growth and succession may result in dramatic reductions in suitable habitat over the next century. Our seral stage-adjusted approach provides conservative and efficient boreal conservation priorities anchored around climatic macrorefugia that are robust to century-long climate change and complement the current protected areas network. [ABSTRACT FROM AUTHOR]

A highly Lewis acidic diphosphonium dication [(C10H6)(Ph2P)2]2+ (1), in combination with a Lewis basic phosphine, acts as a purely phosphorus-based frustrated Lewis pair (FLP) and abstracts hydride from [HB(C6F5)3]_ and Et3SiH demonstrating the remarkable hydridophilicity of 1. The P-based FLP is also shown to activate H2 and C--FI bonds. [ABSTRACT FROM AUTHOR]

Ecosystem distributions are expected to shift as a result of global warming, raising concerns about the long-term utility of reserve systems based on coarse-filter ecosystem representation. We tested the extent to which proportional ecosystem representation targets would be maintained under a changing climate by projecting the distribution of the major ecosystems of Alberta, Canada, into the future using bioclimatic envelope models and then calculating the composition of reserves in successive periods. We used the Marxan conservation planning software to generate the suite of reserve systems for our test, varying the representation target and degree of reserve clumping. Our climate envelope projections for the 2080s indicate that virtually all reserves will, in time, be comprised of different ecosystem types than today. Nevertheless, our proportional targets for ecosystem representation were maintained across all time periods, with only minor exceptions. We hypothesize that this stability in representation arises because ecosystems may be serving as proxies for land facets, the stable abiotic landscape features that delineate major arenas of biological activity. The implication is that accommodating climate change may not require abandoning the conventional ecosystem-based approach to reserve design in favour of a strictly abiotic approach, since the two approaches may be largely synonymous. [ABSTRACT FROM AUTHOR]

Development of hydrocarbon resources across northwest Canada has spurred economic prosperity and generated concerns over impacts to biodiversity. To balance these interests, numerous jurisdictions have adopted management thresholds that allow for limited energy development but minimize undesirable impacts to wildlife. Used for exploration, seismic lines are the most abundant linear feature in the boreal forest and exist at a variety of widths and recovery states. We used American marten (Martes americana) as a model species to measure how line attributes influence species’ response to seismic lines, and asked whether responses to individual lines trigger population impacts. Marten response to seismic lines was strongly influenced by line width and recovery state. Compared to forest interiors, marten used open seismic lines ≥ 3 m wide less often, but used open lines ≤ 2 m wide and partially recovered lines ≥ 6 m wide similarly. Marten response to individual line types appeared to trigger population impacts. The probability of occurrence at the home range scale declined with increasing seismic line density, and the inclusion of behavioral response to line density calculations improved model fit. In our top performing model, we excluded seismic lines ≤ 2 m from our calculation of line density, and the probability of occurrence declined > 80% between home ranges with the lowest and highest line densities. Models that excluded seismic lines did not strongly explain occurrence. We show how wildlife-derived metrics can inform regulatory guidelines to increase the likelihood those guidelines meet intended management objectives. With respect to marten, not all seismic lines constitute disturbances, but avoidance of certain line types scales to population impacts. This approach provides the ecological context required to understand cause and effect relationships among socio-economic and ecological conservation goals. [ABSTRACT FROM AUTHOR]

1-(2-Nitrophenyl)-1-phenylamine and methyl 4-((2-nitrophenyl)amino)benzoate have been transformed into their corresponding urea derivatives through the action of chlorosulfonyl isocyanate. The initial sulfimidate product from the former reaction has sufficient stability so that it can be isolated and characterized as its disodium salt, and this, as well as three other subsequent products, have been characterized by X-ray diffraction. The corresponding intermediary urea was converted into its hydrazine derivative via a Hofmann rearrangement under oxidative conditions. Density functional theory has been used to examine the nature of the intermediates and transition states for the Hofmann rearrangement. There is little theoretical indication for a cyclic aziridinonium intermediate and the transition state between the urea and the isocyanate corresponds to a reactant-like rotation of the planar singlet nitrene before migration and formation of the new N−N bond. [ABSTRACT FROM AUTHOR]

Several studies have emphasized the importance of postfledging survival when estimating avian population growth rates, yet high variation exists in reported estimates. Mechanisms influencing postfledging survival also remain poorly understood. The influences of local habitat quality and landscape context on postfledging movements also remain largely undocumented. We measured daily postfledging survival and movements in Ovenbirds (Seiurus aurocapilla) in selection cut plots (30-40% basal area removal) and controls. Specifically, we tested predictions from the "concealment" hypothesis (higher survival/shorter movements with increased fledgling concealment), "body condition" hypothesis (higher survival/longer movements with increased body mass), and "predator abundance" hypothesis (higher survival/shorter movements when predator abundance is low) by monitoring fledgling survival (n = 55) and movements (n = 41) during the first 2 weeks postfledging. Fledglings were monitored over 2 breeding seasons in S pairs of experimental plots, 25 ha each (1 control and 1 treated plot per pair), located in mature hardwood stands. We found support for an effect of predator abundance on survival (i.e. effects of plot-level abundance of red squirrels and year). Models including habitat variables or body mass received weak support. A positive trend for effect of body mass on movement between successive locations was found but no evidence for an effect of predator abundance or habitat variables. These findings indicate that spatiotemporal variation in predator abundance was a key factor determining daily postfledging survival rate in this Ovenbird population; however, predator abundance did not influence movement rate, suggesting that fledgling Ovenbirds were unable to respond to predation risk. [ABSTRACT FROM AUTHOR]

ABSTRACT The development of hydrocarbon resources in northwestern Canada has resulted in a vast network of seismic lines. Seismic lines are a conservation concern because they are believed to alter the use of space by predators and ultimately change predator-prey relationships. Such changes are believed to be a key factor influencing declines in boreal woodland caribou ( Rangifer tarandus caribou). Using remote wildlife cameras, we measured the behavioral response of a known caribou predator, the black bear ( Ursus americanus), to seismic lines at 2 spatial scales. At the line scale, we compared black bear use of lines that varied in width and vegetation recovery state to undisturbed forest interior locations. At a 5-km2 scale, we compared the probability of bear use across a continuum of seismic line density. At both spatial scales, we also tested for an interaction between bear use of seismic lines and use of upland and lowland forest types. Black bears used most types of seismic lines more frequently than undisturbed forest interior and upland forest more than lowland forest. We found no evidence of an interaction between lines and forest type, as the relative difference in seismic line versus forest interior use was the same in lowland and upland forest. At the 5-km2 scale, we found no evidence of increased use of lowland forest in areas with greater seismic line density. Thus, seismic lines did not appear to increase black bear use of lowland forest types per se. However, bears used seismic lines more than forest interiors, which might alter their ability to locate and capture caribou and other ungulate prey, thereby creating the potential for altered predator-prey dynamics in landscapes with seismic lines. Bears do not appear to use seismic lines ≤2 m wide more often than the forest interior. We suggest that where new seismic lines are constructed, those seismic lines should be a maximum width of 2 m to reduce the potential for altered predator-prey dynamics in areas being developed for oil and gas extraction. © 2014 The Wildlife Society. [ABSTRACT FROM AUTHOR]

This brief review describes some recent research on the effect of varying temperatures (−150 to 600 °C) and external pressures (up to ∼5 GPa) on the stability of various artists' pigments. These pigments, some of which have been known for centuries, are remarkably stable under such non-standard conditions. [ABSTRACT FROM AUTHOR]

Background:Retinoblastoma is an eye tumour of childhood that occurs in heritable and non-heritable forms. In the heritable form, there is a predisposition to the development of non-ocular subsequent primary tumours (SPTs).Methods:This study included 1927 retinoblastoma patients diagnosed in Britain from 1951 to 2004. Ascertainment was through the (UK) National Registry of Childhood Tumours; cases were followed-up for the occurrence of SPTs. Standardised incidence ratios (SIRs) were calculated.Results:We identified 169 SPTs in 152 patients. The SIR analysis included 145 SPTs with cancer registrations from the years 1971 to 2009. These tumours occurred in 132 patients: 112 of the 781 heritable and 20 of the 1075 (presumed) non-heritable cases under surveillance at the start of this period developed at least one registered SPT. The SIRs for all tumours combined were 13.7 (95% confidence interval 11.3-16.5) in heritable cases and 1.5 (0.9-2.3) in non-heritable cases. The main types of SPT in the heritable cases were leiomyosarcoma, (31 cases; SIR 1018.7 (692.2-1446.0)), osteosarcoma (26 cases; SIR 444.6 (290.4-651.4)), and skin melanoma (12 cases; SIR 18.6 (9.6-32.4)).Conclusion:The risk of SPTs in heritable retinoblastoma is extremely high. This has important implications for the clinical follow-up and counselling of survivors and their families. [ABSTRACT FROM AUTHOR]

Abstract: Public demand to conserve biodiversity has resulted in increased monitoring efforts for a vast number of species. Faced with reporting on the large amounts of information generated by biodiversity monitoring, there is a desire to have state variables that simplify this complexity. Intactness indices describe the deviation of the state of biodiversity from a specified reference condition. An effective intactness index should not only statistically describe changes in biodiversity when change occurs but also resonate with people in a way that they have a clear picture of the type of change that has occurred. We used an online survey to evaluate whether public perception of cumulative impacts as viewed through images of disturbed boreal landscapes was correlated with actual indices of avian biodiversity intactness. We found people accurately ranked landscapes with the most human disturbance relative to an undisturbed reference state. The variable the best predicted perceived intactness was the proportion of mature forest cover remaining. Dissection by roads and fragmentation effects by forestry, agriculture, and urbanization explained less but a significant amount of variation. Biocentric individuals and non-hunters viewed landscapes as generally being less intact. Absolute intactness scores from field data deviated from perceived intactness. Landscapes with little human disturbance (i.e. a single road) were perceived to have lower intactness than what was actually observed in bird communities and landscapes with no forest were perceived as being more impacted than they were. Intactness indices can enhance understanding of biodiversity change but caution must be exercised to ensure a clear understanding of what the absolute value of indices represent. [Copyright &y& Elsevier]

The article discusses the results of a study that assesses the nest fate accuracy and nest productivity estimates by field observation using video monitoring. The study shows that video observers correctly identified 85 percent of nest fates and overestimated by 35 percent the nest productivity. It adds that population growth rates were overestimated by 6 percent and field estimates were less accurate when nestling age reached the estimated fledge date.

The article presents a study which aims to estimate the effective detection radius (EDR) of point-curve surveys throughout Boreal Canada. The study employed binomial distance models and compare them to Partners in Flight's maximum detection distance (MDD). Results revealed that binomial EDRs had an average of 4% positive bias across the 86 species and 30-82% for two species when compared with EDRs with the use of multinomial distance sampling.

Invasional meltdowns, in which facilitation between species causes an accelerating increase in the number of introduced species or impacts, can cause large impacts in invaded systems. Earthworm invasion of northern forests has been suggested as a meltdown, with litter-dwelling species altering soil structure and facilitating mineral-soil or deep-burrowing earthworms that may be less capable of invading intact forest floors. We examined facilitation and synergistic effects of a litter-dwelling species ( Savigny, 1826) and a deep-burrowing species ( L., 1758). Boreal forest soil cores were inoculated with D. octaedra, L. terrestris, both species, a higher density of L. terrestris, or no worms. After 4.5 months, we found no differences in survival or biomass between treatments for either species. Cocoon production did not differ for L. terrestris, but D. octaedra produced significantly fewer cocoons with L. terrestris. The two species had an additive effect on organic horizon depths and bulk densities. Thus, they did not appear to facilitate each other or have synergistic effects as would be predicted in an invasional meltdown. [ABSTRACT FROM AUTHOR]

Abstract: Statistical models that describe species-environmental relationships are important components within many wildlife conservation strategies. These models are typically developed from studies conducted on small geographic scales (hundreds of square kilometres), representing a relatively small range in environmental conditions. Such local models from local studies are often then extrapolated to predict the suitability of other unsampled regions. The value of many models would be increased by considering larger-scale processes that might be structuring spatial patterns across species distributions. We examined home-range habitat selection by burrowing owls throughout the mixed prairie grassland region of western Canada (180,000km2) to determine whether owl selection for biotic factors changes along abiotic gradients. Specifically, we classified 37 explanatory variables into five categories (geography, grassland fragmentation, land-use, soil, and climate), created models for each set of variables, and evaluated the predictive ability of each model. We then examined interaction effects to determine if the relationship between land cover variables and the probability of owl home-range selection varied within large-scale abiotic criteria. Our results showed that soil and climate produce the most predictive models of burrowing owl home-range selection and create unique environmental conditions for owls which are independent of land cover at this scale. This study provides new insight into burrowing owl habitat requirements, and strengthens the case for considering large-scale abiotic gradients when prioritizing areas for species conservation. [Copyright &y& Elsevier]

Habitat suitability models allow for predictive modeling of the supply of wildlife habitat through time under various forest harvesting scenarios. These models often rely on remotely sensed data in a forest resource inventory (FRI). However, the level of detail and (or) the accuracy of a FRI may be insufficient to accurately predict habitat suitability for forest birds. We tested if detailed vegetation measurements created habitat suitability models with better predictive power than models that used FRI data alone and if rough estimates of shrub cover were sufficient to supplement FRI data to create models with similar predictive power. For 28 species of forest birds, we found that less of the variation in abundance and (or) occurrence (% deviance explained) could be explained by models using FRI data alone (34% ± 2%) than by models using detailed vegetation information (40% ± 2%). However, when shrub density rank was included with FRI data, we found no difference in the deviance explained by the two model sets (39% ± 2% vs. 40% ± 2%). The best-fitting models containing the same vegetation parameters but using different methods of vegetation sampling were similar. These results suggest that coarse habitat classification schemes may be as effective in describing the major variance in bird community structure in the boreal forest as detailed vegetation inventory data. [ABSTRACT FROM AUTHOR]

1. Roads are an important conduit for the spread of invasive species. Road age is a key factor that could influence the susceptibility of roads to invasion as older roads are typically subject to higher cumulative levels of human disturbance and propagule pressure than younger roads. We investigated the effects of road age on the spread of non-native earthworms, which act as ecosystem engineers. 2. We sampled earthworms and habitat variables at 98 roads in the boreal forest of Alberta, Canada, to determine the influence of road age on non-native earthworm occurrence at the landscape level. The extent and rate of local spread were also assessed at seven sites adjacent to old and young roads. Generalized estimating equations and zero-inflated negative binomial regression were used to analyze landscape- and local-level results, respectively. We used our models to create maps that predict the current and potential future extent of earthworms in north-eastern Alberta. 3. Probability of earthworm occurrence and extent of spread increased as road age increased. Areas closer to agriculture and towards the south and west of our study area were also significantly more likely to be invaded by earthworms. 4. Our spread model indicated that approximately 9% of the boreal forest of north-eastern Alberta is likely invaded by earthworms currently. This is projected to increase to 49% of suitable forest habitat over the next 50 years as human development intensifies in this region. 5. Synthesis and applications. Although the effects of roads and linear features are commonly investigated in relation to native species, our results emphasize the importance of considering the impacts of linear feature creation on the spread of invasive species. We demonstrate that road age in particular can be an important factor affecting the spread of invasive species. In the boreal forest, reducing the number of roads being constructed, restricting traffic, and reclaiming temporary roads will be critical to reduce the future extent of earthworm invasions. [ABSTRACT FROM AUTHOR]

The effects of human activities in forests are often examined in the context of habitat conversion. Changes in habitat structure and composition are also associated with increases in the activity of people with vehicles and equipment, which results in increases in anthropogenic noise. Anthropogenic noise may reduce habitat quality for many species, particularly those that rely on acoustic signals for communication. We compared the density and occupancy rate of forest passerines close to versus far from noise-generating compressor stations and noiseless well pads in the boreal forest of Alberta, Canada. Using distance-based sampling, we found that areas near noiseless energy facilities had a total passerine density 1.5 times higher than areas near noise-producing energy sites. The White-throated Sparrow (Zonotrichia albicollis ), Yellow-rumped Warbler (Dendroica coronata ), and Red-eyed Vireo (Vireo olivaceus ) were less dense in noisy areas. We used repeat sampling to estimate occupancy rate for 23 additional species. Seven had lower conditional or unconditional occupancy rates near noise-generating facilities. One-third of the species examined showed patterns that supported the hypothesis that abundance is influenced by anthropogenic noise. An additional 4 species responded negatively to edge effects. To mitigate existing noise impacts on birds would require approximately $175 million. The merits of such an effort relative to other reclamation actions are discussed. Nevertheless, given the $100 billion energy-sector investment planned for the boreal forest in the next 10 years, including noise suppression technology at the outset of construction, makes noise mitigation a cost-effective best-management practice that might help conserve high-quality habitat for boreal birds. [ABSTRACT FROM AUTHOR]

We examined the spatial pattern of Canada lynx (Lynx canadensis Kerr, 1792) relative to its southern range edge at the boreal plains - prairie ecotone in Alberta, Canada. Relative to the original distribution of boreal forest in our study area, lynx range seems to have contracted up to 22%. In 100 km2 sampling areas, lynx occupancy rate increased 1.93 times every 100 km farther (north) from the range edge that we sampled. An information-theoretic approach was used to evaluate 31 models to see which environmental factors were the best predictors of this spatial pattern. Lynx were strongly correlated with track counts of their primary prey, the snowshoe hare (Lepus americanus Erxleben, 1777), but this did not explain the observed increase in occupancy farther north. Rather, lynx occupancy was lower in areas with higher road densities and this effect was magnified in areas where coyote (Canis latrans Say, 1823) activity was highest. The inclusion of these effects rendered the south-north pattern no longer significant. The rapid pace of road building and associated development in Alberta’s boreal forest seems to be reducing habitat quality for Canada lynx, particularly at the southern edge of its range. This may be leading to range contractions for lynx in Alberta, much like has happened elsewhere in North America. [ABSTRACT FROM AUTHOR]

Population genetic studies can help to determine whether invasive species are established via single vs. multiple introduction events and also to distinguish among various colonization scenarios. We used this approach to investigate the introduction of Dendrobaena octaedra, a non-native earthworm species, to the boreal forest of northern Alberta. The spread of non-native earthworms in forested systems is not well understood, although bait abandonment and vehicular transport are believed to be important. Mitochondrial DNA sequencing revealed that multiple introductions of this species have occurred in northern Alberta, although individual populations may have been established by either single or multiple invaders introduced on one or more occasions. There was no relationship between genetic distances and either geographical distances or distances along road networks, suggesting that human-mediated jump dispersal is more common than diffusive spread via road networks or via active dispersal. As well, genetic diversity was significantly greater at boat launches than roads, indicating that multiple introductions may be more likely to occur at those locations. Focusing management efforts on areas where multiple introductions are likely to occur may help to reduce invasive species’ potential for adaptive evolution and subsequent rapid spread. [ABSTRACT FROM AUTHOR]

Given Hume's theory of belief and belief production it is no small task to explain how it is possible for a belief in a miracle to be produced. I argue that belief in a miracle cannot be produced through Hume's standard causal mechanisms and that although education, passion, and testimony initially seem to be promising mechanisms for producing belief in a miracle, none of these is able to produce the belief in a miracle. I conclude by explaining how this poses a problem for Hume's theory of belief and I briefly investigate the alternatives available for solving this problem. [ABSTRACT FROM AUTHOR]

1. Anthropogenic noise is rapidly increasing in wilderness areas as a result of industrial expansion. While many road studies have attempted to assess the effects of industrial noise on birds, conflicting factors such as edge effects often inhibit the ability to draw strong conclusions. 2. We assessed pairing success and age distribution of male ovenbirds Seiurus aurocapilla in the boreal forest of Alberta, Canada, in areas around noise-generating compressor stations compared with areas around habitat-disturbed, but noiseless, wellpads. This allowed us to control for edge effects, human visitation and other factors that are not controlled for in studies of noise generated by roads. Generalized estimating equations (GEE) were used to assess the impacts of noise on ovenbird pairing success, age structure and body morphology. 3. We found a significant reduction in ovenbird pairing success at compressor sites (77%) compared with noiseless wellpads (92%). These differences were apparent regardless of territory quality or individual male quality. Significantly more inexperienced birds breeding for the first time were found near noise-generating compressor stations than noiseless wellpads (48% vs. 30%). 4. While there are multiple proximate explanations for these results, the ultimate cause of the changes seems to be noise pollution. We hypothesize that noise interferes with a male's song, such that females may not hear the male's song at greater distances and/or females may perceive males to be of lower quality because of distortion of song characteristics. 5. Synthesis and applications. This work demonstrates that chronic background noise could be an important factor affecting bird populations. It can impact upon pairing success and age structure of passerines; in boreal Alberta this could pose a problem for certain species as energy development expands rapidly. [ABSTRACT FROM AUTHOR]

Despite widespread recognition of the importance of forest loss and fragmentation on biodiversity, the extent and rate of forest loss even in temperate regions remains poorly understood. We documented forest loss and assessed whether road density, rural developments, land quality for agriculture, and land ownership influenced the distribution and rate of change in forest cover for the entire boreal transition zone (49,846 km2 ) of Saskatchewan, Canada. We used landscape data taken from the Canadian Land Inventory database in forest cover (1996) and Landsat thematic mapper data (1994) to study changes between 1966 and 1994. Forest covered 17,873 km2 of the study area in 1966 and 13,504 km2 in 1994. This represents an overall conversion of 73% of the boreal transition zone in Saskatchewan to agriculture since European settlement and an annual deforestation rate of 0.89% over the last 28 years, a rate approximately three times the world average. Mixed-regressive, spatially autoregressive models explained a considerable portion of the variation in forest cover (r 2 = 0.83) remaining on the landscape and suggested that less forest remained on lands that (1) were privately owned, (2) had soils with high suitability for agriculture, (3) had high road density, and (4) were in the southern portions of the study area. Strong spatial autocorrelation in the data indicated that areas of remaining forest tended to be spatially clustered. Our ability to predict where deforestation occurred between 1966 and 1994 was poor when we excluded the spatial autocorrelation terms from our model, but it was clear that deforestation was more likely to occur on privately owned lands than on those managed by the provincial government. Despite dramatic changes to forested areas in the boreal transition zone, and despite the importance of this area to a wide variety of forest-dwelling wildlife, no programs are in place to slow or halt deforestation. [ABSTRACT FROM AUTHOR]

Presents a study which reported survival and recapture rates from four years of banding adult American Redstarts, Setophaga ruticilla and Ovenbirds, Seiurus aurocapillus from sites in the boreal forest of central Saskatchewan. Methods; Results and discussion.

Examines the annual survival of male Ovenbirds in fragmented and forested boreal landscapes. Increase of mortality of birds following fragmentation; Population dynamics of boreal forest songbird; Landscape-level factors influencing habitat quality for songbirds.

Presents a study which determined the importance of red squirrels as predators of forest songbirds nesting in forest fragments. Comparison of survival rates of artificial nests before and after squirrels were removed; Methods; Results and discussion.

Reports on the movement of male ovenbirds during the post-fledging period to determine if movement patterns differed in landscapes dominated by agriculture versus those dominated by forest. Comparison of movement patterns between males seen without young and those seen with young; Percentage of ovenbirds that are most likely to cross gaps in the fragmented landscape; Interaction between landscape and breeding status.

Presents information on a study that compared the pairing success of territorial male Ovenbirds (Seiurus aurocapillus) in forest fragments created by forestry and agriculture to contiguous forest plots in Saskatchewan between 1996 and 1998. Methodology of the study; Results and discussion on the study.

Despite the existence of a Black middle class in the United States (U.S.) for at least 100 years, scant research has been conducted on the Black elderly that has not been concerned with the level of their poverty or the incidence of morbidity and mortality among them. This study examined the living conditions and analyzed the determinants of quality of life satisfaction among 59 Black women 75 years and older. The findings indicate that satisfaction with quality of life is significantly associated with belonging to a family and social support network that includes church, as well as maintaining physical health independence and personal safety. These findings hold implications for the design of social work services to the Black middle income elderly as well for future development of public policy that focuses on providing effective help for older Americans in all their diversity. [ABSTRACT FROM AUTHOR]