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The limiting trade-off between expediency and accuracy is well exemplified by the monitoring of bats, more specifically since the onset of the White-Nose Syndrome in North America. Acoustic detection is a way of circumventing the difficulties of catching bats, and monitoring is usually done either with transects or fixed recording points, the latter generally being assumed to be superior. However, little has been done until now to assess each method's ability to maximize the quality of recordings and the number of species detected, to account for the temporal variability of bat activity, and to account for the variability in habitats and the spatial patterns of bat activity. We tested whether transects could yield similar results as fixed points for every of those aspects of accurate and reliable bat monitoring. We found it to be true for recording quality and the detection of peaks of activity, but found that either method was little affected by weather and landscape attributes. We conclude that the use of transects is a valid choice for long-term monitoring, as it performs comparably to fixed recording points and maximizes the number of detections per sampling unit. However, transects tend to record a greater proportion of migratory bats than fixed recording points, a bias which should be considered in the assessment of the state of particular species' populations. [ABSTRACT FROM AUTHOR]

Severe crown fires are determining disturbances for the composition and structure of boreal forests in North America. Fire cycle (FC) associations with continental climate gradients are well known, but smaller scale controls remain poorly documented. Using a time since fire map (time scale of 300 years), the study aims to assess the relative contributions of local and regional controls on FC and to describe the relationship between FC heterogeneity and vegetation patterns. The study area, located in boreal eastern North America, was partitioned into watersheds according to five scales going from local (3 km2) to landscape (2800 km2) scales. Using survival analysis, we observed that dry surficial deposits and hydrography density better predict FC when measured at the local scale, while terrain complexity and slope position perform better when measured at the middle and landscape scales. The most parsimonious model was selected according to the Akaike information criterion to predict FC throughout the study area. We detected two FC zones, one short (159 years) and one long (303 years), with specific age structures and tree compositions. We argue that the local heterogeneity of the fire regime contributes to ecosystem diversity and must be considered in ecosystem management. [ABSTRACT FROM AUTHOR]

Major landscape changes caused by humans may create strong selection pressures and induce rapid evolution in natural populations. In the last 100 years, eastern North America has experienced extensive clear-cutting in boreal areas, while afforestation has occurred in most temperate areas. Based on museum specimens, I show that wings of several boreal forest songbirds and temperate songbirds of non-forest habitats have become more pointed over the last 100 years. In contrast, wings of most temperate forest and early-successional boreal forests species have become less pointed over the same period. In contrast to wing shape, the bill length of most species did not change significantly through time. These results are consistent with the "habitat isolation hypothesis," i.e., songbirds evolved in response to recent changes in the amount of available habitat and associated implications for mobility. Rapid morphological evolution may mitigate, without necessarily preventing, negative consequences of habitat loss caused by humans through direct exploitation or climate change. [ABSTRACT FROM AUTHOR]

This paper examines the processes leading to the spontaneous development of industrial recycling linkages. The famous 'industrial symbiosis' that formed in and around the Danish city of Kalundborg and other similar cases in other parts of Europe and North America are taken as a point of departure. These recycling linkages were found to be primarily the result of the entrepreneurial actions that aimed to create value out of by-products and/or to reduce production costs through the adoption of new inputs. As the incentives driving this behaviour are not new, this paper contends that 'industrial symbiosis' is not, as is usually believed, a break with past practices, but rather a widespread phenomenon that has been neglected by contemporary researchers. Historical evidence is provided to support this claim. It is argued that while significant inter-firm recycling linkages will spontaneously emerge at the regional level, these should not be forced at the expense of inter-regional linkages. [ABSTRACT FROM AUTHOR]

This experimental study presents an innovative method for establishing a willow (Salix spp.) shrub vegetation cover on disturbed sites in North America. Willow microcuttings of Salix miyabeana 'SX61', S. eriocephala 'S25' and S. purpurea 'Fish Creek' were selected to test the potential of shortened willow cuttings. We evaluated the effect of three factors related to microcutting assemblages (monoculture and polyculture), the presence or absence of a companion herbaceous plant and two types of substrate (same soil, but one with compost and one without). The objectives were to assess 1) the potential growth of willow microcuttings in open site conditions, 2) the influence of soil amendments on the establishment of willow microcuttings and 3) the influence of diversity on biotic resistance. The results showed a greater establishment rate, stem height and number of shoots per microcutting without the presence of an herbaceous plant. The plots planted without compost showed better establishment rates, especially those in the polyculture plots. The presence of compost increased the production of number of shoots per microcutting and tended to increase stem height. The presence of an herbaceous plant was related to higher plant cover, but no relationship with biotic resistance was observed. Although willow cover did not significantly affect relative growth of undesirable tree species seedlings (Betula populifolia and Acer rubrum), we observed that plant cover tended to reduce the relative growth rate. Consequently, this preliminary test of using microcuttings as an alternative approach to establishing a dense shrub cover showed good potential to restore disturbed sites and limit tree encroachment in open sites, reducing environmental and economic costs. [ABSTRACT FROM AUTHOR]