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Limber pine (Pinus flexilis E. James) is under threat from white pine blister rust (WPBR), mountain pine beetle, drought, and fire suppression across its range in western North America. In 2003-2004, we established 85 plots to assess the mortality and incidence of WPBR on limber pine, and remeasured them in 2009. Infection was evident in 74% of the plots in 2003-2004 and 88% of the plots in 2009. The proportion of dead trees increased from 32% in 2003-2004 to 35% in 2009. The percentage of live trees infected increased from 33% in 2003-2004 to 43% in 2009. Mean live limber pine basal area in 2009 ranged from 0.03 to 77.8 [m.sup.2]/ha per plot. Twenty (24%) of the plots had no seedlings in the first measurement, but only 15% in the second measurement. Seedling infection was low (8% in 2003-2004 and 4% in 2009). In 12 plots that were measured three times, mortality increased from 30% of all trees in 1996 to 50% in 2003, then decreased to 46% in 2009. Infection decreased from 73% of live trees in 1996 to 46% in 2003, then increased to 66% in 2009. High mortality and infection levels suggest that the long-term persistence of many limber pine populations in the southern part of the study area are in jeopardy, and continued monitoring is needed to assist with management decisions. Resume: Le pin flexible (Pinus flexilis E. James) est menace par la rouille vesiculeuse du pin blanc (RVPB), le dendroctone du pin ponderosa, la secheresse et la suppression du feu partout dans son aire de repartition dans l'ouest de l'Amerique du Nord. En 2003-2004, nous avons etabli 85 placettes pour evaluer la mortalite et l'incidence de la RVPB sur le pin flexible et nous les avons remesurees en 2009. L'infection etait evidente dans 74 % des placettes en 2003-2004 et 88 % des placettes en 2009. La proportion des arbres morts a augmente de 32 % en 2003-2004 a 35 % en 2009. Le pourcentage d'arbres vivants infectes est passe de 33 % en 2003-2004 a 43 % en 2009. La surface terriere moyenne des pins flexibles vivants variait en 2009 de 0,03 a 77,8 [m.sup.2]/ha par placettes. Il n'y n'avait aucun semis dans 24 % des placettes lors de la premiere mesure contre seulement 15 % lors de la seconde mesure. Le taux d'infection des semis etait faible (8 % en 2003-2004 et 4 % en 2009). Dans 12 placettes remesurees trois fois, la mortalite est passee de 30 % de tous les arbres en 1996 a 50 % en 2003 puis a diminue a 46 % en 2009. Le taux d'infection est passe de 73 % des arbres vivants en 1996 a 46 % en 2003 puis a augmente a 66 % en 2009. Les taux eleves d'infection et de mortalite indiquent que la persistance a long terme de plusieurs populations de pin flexible dans la partie sud de la zone d'etude est menacee et qu'un suivi continu est necessaire pour faciliter les decisions d'amenagement. [Traduit par la Redaction], Introduction Limber pine (Pinus flexilis E. James) is a five-needled white pine that ranges from southwestern Alberta and southeastern British Columbia, south to New Mexico, Arizona, and eastern California, with [...]

Harlequin Ducks (Histrionicus histrionicus) were captured on breeding streams in Alberta, Canada from 1995–2018. Measurements for exposed culmen, tarsus bone, and wing length, and mass, were significantly larger for adult males than those for adult females, while only tarsus was significantly larger for male ducklings than for females. The repeatability of tarsus and culmen measurements across time for the same individuals was significantly different from 0, indicating high consistency. We used logistic regression of culmen and tarsus length of adult ducks to identify the best model to predict the sex of adults, then constructed a classification and regression tree to predict the sex of a test set of juveniles that had been banded and sexed as ducklings but that were sexed by plumage when resighted as adults. The model with the highest accuracy (96.9%) and lowest number of individuals in the zone of uncertainty (thus sexed as unknown) was tarsus < 37.5 mm (classify as females) or ≥ 38.0 mm (classify as males). Individuals in the zone of uncertainty with a penis sheath should be sexed as male, but individuals without a penis sheath that do not match the appropriate tarsus length should be sexed as unknown. [ABSTRACT FROM AUTHOR]

Whitebark pine (Pinus albicaulis Engelm.), a keystone species in subalpine ecosystems of western North America, is under threat across its range from white pine blister rust, mountain pine beetle, fire exclusion, and climate change. Loss of whitebark pine is predicted to have cascading effects on many ecosystem services. We remeasured 115 whitebark pine plots in the Canadian Rocky Mountains to determine whether infection and mortality rates from blister rust were changing over time and (or) latitude. Average rust infection of trees among plots increased from 42% in 2003-2004 to 52% in 2009, while mortality increased from 18% to 28%. In eight plots that have been measured three times, infection increased from 43% of live trees in 1996 to 70% in 2003 and 78% in 2009. Mortality increased from 26% to 65% in the same time period. Overall, infection and mortality have increased 3%/year over the 13 years of the study. Incidence of infection and mortality was highest among plots in the southern part of the study area, particularly on the western side of the Continental Divide. The slowing rates of infection and mortality that we found suggest that some level of natural selection may already be occurring in areas with high levels of both. Resume: Le pin a ecorce blanche (Pinus albicaulis Engelm.), une espece cle dans les ecosystemes subalpins de l'Ouest de l'Amerique du Nord, est menace partout dans son aire de repartition par la rouille vesiculeuse du pin blanc, le dendroctone du pin ponderosa, l'exclusion du feu et les changements climatiques. On prevoit que la perte du pin a ecorce blanche aurait des repercussions en cascade sur plusieurs services de l'ecosysteme. Nous avons remesure 115 places echantillons contenant du pin a ecorce blanche dans les montagnes Rocheuses canadiennes pour determiner si les taux d'infection et de mortalite par la rouille vesiculeuse changeaient avec le temps et la latitude. Le taux moyen d'infection des arbres par la rouille vesiculeuse dans les places echantillons a augmente de 42% en 2003?2004 a 52% en 2009 tandis que la mortalite a augmente de 18% a 28%. Dans huit places echantillons qui ont ete mesurees trois fois, le taux d'infection est passe de 43% des arbres vivants en 1966 a 70% en 2003 et 78% en 2009. La mortalite a augmente de 26% a 65% durant la meme periode. Dans l'ensemble, les taux d'infection et de mortalite ont augmente de 3% par annee durant le cours de l'etude qui a dure 13 ans. L'incidence de l'infection et de la mortalite etait la plus forte parmi les places echantillons situees dans la partie sud de la zone d'etude. Le ralentissement que nous avons observe dans l'augmentation des taux d'infection et de mortalite indique qu'un certain degre de selection naturelle est peutetre deja a l'ouvre dans les regions ou l'infection et la mortalite atteignent des niveaux eleves. [Traduit par la Redaction], Introduction Whitebark pine (Pinus albicaulis Engelm.), a keystone species in subalpine ecosystems of western North America, is under threat across the species' range. It is being impacted by white pine [...]

Photosynthetic gas-exchange characteristics were measured in Pinus flexilis James (limber pine) during two drought years in a xeric, subalpine ecosystem of the Rocky Mountains. Limber pine exhibited conservative water-use traits, including low specific leaf area, leaf nitrogen, stomatal conductance, transpiration (E), and light-saturated net photosynthesis ([A.sub.max]), but exhibited high needle longevity, water-use efficiency ([A.sub.max]/E), and stable carbon isotope composition. Net photosynthesis declined strongly with leaf-to-air vapour pressure deficit, resulting in a bimodal seasonal pattern of [A.sub.max]. Although very little gas exchange was observed in late summer, photosynthetic activity extended into October. The avoidance of gas exchange during high atmospheric demand maximized whole-season water-use efficiency. Leaf temperature and leaf-to-air vapour pressure deficit were higher on south-facing slopes during both moderate (2006) and severe (2007) drought. Severe drought caused lower stomatal conductance and E on the southeast-facing slope, but neither [A.sub.max] nor canopy reflectance indices differed among slope aspects. Although [A.sub.max] was lower in 2007 than 2006, branch- length increment did not differ. Foliar stable carbon isotope composition was higher in needles produced in dry years but did not vary among slope aspects. These results indicate that physiological acclimation to water stress prevented among-aspect differences in [A.sub.max] and that shoulder-season photosynthesis may become increasingly important in a warmer climate. Les caracteristiques des echanges gazeux associes a la photosynthese ont ete mesurees chez le pin flexible (Pinus flexilis James) pendant deux annees de secheresse dans un ecosysteme subalpin xerique des montagnes Rocheuses. Le pin flexible avait des traits associes a une utilisation conservatrice de l'eau, incluant une surface foliaire specifique, un contenu en azote foliaire, une conductance stomatale (g,), une transpiration (E) et une photosynthese nette a saturation lumineuse ([A.sub.max]) faibles, mais une longevite des aiguilles et une efficacite d'utilisation de l'eau (WUE); [A.sub.max]/E) elevees ainsi qu'une composition isotopique stable du carbone ([δ.sup.13]C). La photosynthese nette a fortement diminue avec le deficit de saturation, ce qui a entraene un patron saisonnier bimodal de [A.sub.max]. Bien que tres peu d'echanges gazeux aient ete observes a la fm de l'ete, l'activite photosynthetique s'est poursuivie jusqu'en octobre. L'arret des echanges gazeux lorsque le deficit de saturation etait elevee a maximise WUE sur l'ensemble de la saison. La temperature des feuilles et le deficit de saturation etaient plus eleves sur les pentes exposees au sud en periode de secheresse tant moderee (2006) que severe (2007). La secheresse severe a reduit g, et E sur les pentes exposees au sud-est mais ni [A.sub.max], ni l'indice de reflectance de la canopee n'etaient differents peu importe l'orientation de la pente. Meme si [A.sub.max] etait plus faible en 2007 qu'en 2006, l'accroissement en longueur des branches etait semblable. La composition foliaire en [δ.sup.13]C etait plus elevee lors des annees seches mais ne variait pas selon l'orientation de la pente. Ces resultats indiquent que l'acclimatation physiologique au stress hydrique a elimine les differences de [A.sub.max] dues a l'orientation et que la photosynthese qui a lieu durant le printemps et l'automne pourrait devenir de plus en plus importante sous un climat plus chaud. [Traduit par la Redaction], Introduction Limber pine (Pinus flexilis James) is a long-lived, drought-tolerant tree, distributed over a wide altitudinal and latitudinal range in subalpine ecosystems of western North America. In the Rocky Mountains [...]

Abstract: In 2003-2004, we examined 8031 whitebark pine (Pinus albicaulis Engelm.) trees and 3812 seedling- establishment sites in 170 plots for mortality and incidence of white pine blister rust (Cronartium [...]

At the Inglewood Bird Observatory (IBO), in Calgary, Alberta, we banded 40,033 birds of 119 species: 7,565 during spring (1995-2020) and 32,468 during fall (2002-2020) migration. We present summary statistics for wing length and body mass for 68 species or subspecies. When sample sizes permitted, we analyzed both metrics by age and sex class. Data are presented in three ways: (1) the interquartile range (IQR: the range of the middle 50% of the data), (2) the range of all IBO data for that species, and (3) plus-or-minus two standard deviations (SD) of the mean, which is intended to capture the middle 95% of wing lengths. For most species our wing length ranges are similar to those of Pyle (1997, 2008) and Mulvihill et al. (2004), while mass ranges are more variable compared to Mulvihill et al. (2004) and Dunning (2008). We found that in 42% of the species or subspecies that we analyzed, mean wing lengths were significantly different for adults than for juveniles: 38% were longer while 4% were shorter. Mean male wing length was significantly greater than for females for 90% of our species: 83% of these were longer while 7% were shorter. Sex was a bigger predictor of body mass than age: in 54% of the species males were significantly heavier than females, while in 32% of the species adults were significantly heavier than juveniles. We suggest that whenever possible, identification guides and studies should differentiate between adult and juvenile wing length and body mass ranges, as well as between the sexes. [ABSTRACT FROM AUTHOR]

We compared the influence of different lengths of audio playback on attracting migrating passerines during spring and fall in southwestern Alberta in 2014. The short audio playback was started 1.5 hr before sunrise while the long audio playback was started 4.5 hr before sunrise. During both spring and fall we captured significantly more birds on days when we played the audio lure than on silent days. During spring migration, the short audio was equally as good at attracting birds as was the long audio, whereas during fall migration, the long audio attracted more birds than the short audio. However, there were differences among species, age and/or sex classes. Overall, using a short audio lure seems to be an acceptable compromise between increasing capture rates and early landfall, which may affect behavior or flight resources. [ABSTRACT FROM AUTHOR]

Whitebark pine forests are declining due to infection by white pine blister rust and mountain pine beetle, combined with the effects of climate change and fire suppression. The Canadian Rocky and Columbia Mountains represent a large portion of the whitebark range; a vast area, exemplifying the need for knowledge about whitebark pine stands to target restoration. The aim of our work was to identify variables predicting live tree infection, seedling infection, canopy kill, mortality, and regeneration across this region, and present the results in spatially-explicit formats to assist land managers with restoration. Live tree and seedling infection by white pine blister rust increased over the last decade and cascading effects of the disease are intensifying, including canopy kill and mortality. We show that large diameter trees are more likely to be infected, and the highest infection rates are in southern and western areas. The conditions for seedling infection are more strongly influenced by fine-scale climatic conditions than for trees. Areas with low regeneration are: (1) the dry east slopes where live tree infection is low; and (2) where live tree infection rates are high, suggesting that canopy kill and mortality are influencing regeneration. Results highlight where to target restoration and coordinate across boundaries. [ABSTRACT FROM AUTHOR]