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Anthropogenic development may influence the choices animals make and their resulting reproductive success and survival. If such choices are maladaptive, the impact of anthropogenic change can be catastrophic to small or declining populations. Over the past century, Canada's prairie landscapes have been altered dramatically, with over two‐thirds of its native grasslands now having been converted to cropland. The decline of the endangered Burrowing Owl Athene cunicularia population is assumed to have resulted from this landscape change, yet no causal link has been demonstrated. One hypothesis to explain this population decline is that owls get caught in an ecological trap, whereby they prefer to establish nests at the start of each breeding season in landscapes that later confer lower reproductive success. Agricultural landscapes represent a plausible potential ecological trap because the short and sparse vegetation in annual crops (seeded each spring) is predicted to be attractive nesting/foraging habitat for Burrowing Owls when they arrive from northward migration, yet crops become substantially taller and denser over the growing season so prey are predicted to become less accessible by the time broods have hatched. We tested this ecological trap hypothesis in a 3‐year study, involving 379 Burrowing Owl pairs, across the agricultural landscapes of southern Alberta and Saskatchewan. In support of the hypothesis, Burrowing Owls did prefer to settle in breeding home‐ranges that contained a higher proportion of cropland, and their prey‐delivery rates during brood‐rearing were lower at nests with a higher proportion of cropland growing in the surrounding landscape. However, in contradiction to a key prediction, the number of fledglings produced (range = 0–9) was higher, not lower, for pairs with more actively growing cropland in their landscapes. Therefore, the decline of the Burrowing Owl in Canada does not appear to result from cropland forming an ecological trap during the breeding season. We also found a significant positive relationship between the amount of summer fallow within Burrowing Owl home‐ranges and the quantity of vertebrate prey delivered to the nest and the number of juveniles fledged, highlighting the importance of this declining land use in raptor conservation. [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.