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    The generation of geospatial thematic information for managing and monitoring Canada's boreal ecosystem is essential for researchers, land managers, and policy makers. Canada's boreal region is a vast mosaic of forests, wetlands, rivers and lakes, but anthropogenic disturbances have impacted these ecosystems resulting in habitat loss, fragmentation and threats to biodiversity. Across Canada various geospatial datasets representing anthropogenic disturbance exist for timber harvesting, hydro-electric activity, settlement and oil & gas activities; however, these products often vary in scale, attributes, time period, and mapping technique. Driven by the need for national data as part of the 2011 boreal caribou science assessment, a standardized methodology was developed and implemented to create a single geospatial dataset representing anthropogenic disturbances across a significant portion of Canada’s boreal ecosystem. The boreal ecosystem anthropogenic disturbances (BEAD) data is a vector disturbance dataset of individual linear and polygonal disturbance types that were manually collected through the interpretation of 2008 to 2010 Landsat imagery at a 1:50,000 viewing scale. Summary results identified a total polygonal anthropogenic disturbance footprint of approximately 24 million ha with forest cutblocks accounting for more than 60 % of mapped polygonal disturbance. Linear disturbance features across the boreal total approximately 600,000 km with roads and seismic exploration lines contributing to more than 80 % of the mapped linear disturbances. For distribution and use by the public the data was gridded to a 1km resolution product that can easily be incorporated into a wide variety of applications. Each disturbance type was gridded as the total per km2 (km2 / km2 for polygonal disturbances and km / km2 for linear disturbances). This product consists of 19 individual raster layers - 16 representing different disturbance types, along with layers representing the total linear and total polygonal disturbances separately and a binary mask layer defining all cells that contain disturbance values

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    We monitored a colony of Cliff Swallows (Petrochelidon pyrrhonota) nesting on an artificial nesting structure that had been built for this species, near the Dezadeash River in Haines Junction, Yukon (60o 44’ 58” N/ 137o 30’ 33” W). We took photographs of the nesting surface of each of the 16 nesting panels of the structure, several times per year during 2013-2016 and once in 2017. From each photograph, nests and any visible adult birds were counted, and changes since the previous photo of that same panel were noted. In this way we tracked persistence of nests over the winter, timing of arrival of the birds, the progress of nest building, loss of nests or parts of nests that fell to the ground, and the number of nests that were apparently active each year. A nest was considered active in a given year if an adult was visible inside it in at least one photo, or if material (mud) was added to the nest.

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    Aerial surveys were performed in the Rasmussen Lowlands, Nunavut, to determine the numbers and distribution of Greater White-fronted Geese and other waterfowl species. Surveys were carried out in the Lowlands from 20-24 June 1994 and 20-25 June 1995. The survey procedure included flying straight transects in a float-equipped Bell 206L helicopter at 45 m altitude above ground and at a ground speed of 80-100 km/hr. Transects were oriented east-west and spaced at 5 km intervals in areas expected to have greater densities of geese and 10 km intervals in areas with lower expected densities. All transects were divided into 2 km segments that were used as a basis for recording data. Transects were of differing lengths. Surveys were performed with two observers, one seated in the left front seat and the other in the right rear seat that was equipped with a bubble window for better viewing. All observations of geese and other highly visible birds within an estimated 200 m of the flight path were recorded. Lesser Snow Geese typically nest in large colonies and are not easily surveyed using widely spaced aerial transects. Therefore, on top of counting the numbers of Snow Geese on the regular transects (all non-breeders in flocks of three or more birds), total counts of nesting Snow Geese were carried out by flying over colonies at a height of 230 m and counting all geese within 1 km of each side of the helicopter. Transects were spaced at 2 km distances, and during the transect and colony surveys, the plumage colour of the birds (blue or white) was recorded whenever all individuals in a flock or pair could be readily identified to colour phase. Complete metadata is available in downloadable files.

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    We conducted a species-specific survey for Common Nighthawk (Chordeiles minor) near the northwestern limit of the species’ breeding distribution, in order to investigate relative abundance and also to determine whether a species-specific survey protocol being established for Canada would be appropriate in the north. Activity of Common Nighthawk was documented using 10-stop to 20-stop roadside surveys conducted during the night in northern British Columbia and southern and central Yukon in 2014-15, mostly along established North American Breeding Bird Survey (BBS) routes. We used a total of 19 roadside survey routes, including 14 standardized routes which used the first 20 odd-numbered stops of established BBS routes and were conducted in both 2014 and 2015. The other five routes included one BBS-based route which was completed only partially in 2014 but completely in 2015; one BBS-based route where non-standard stops were surveyed, run only in 2014; and three routes with 10-20 stops which were selected non-randomly and run in both years. Two of the standard routes were also run a second time in the 2014 season. Overall, 738 point counts were conducted on 19 routes over two years. Each survey started one hour before sunset; survey stops were 1.6 km apart, and the count at each stop was 6 minutes long.

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    We documented seasonal and daily activity patterns of Common Nighthawk (Chordeiles minor) near Whitehorse, Yukon, to evaluate the appropriateness at higher latitudes of national survey protocols for this species. Nighthawk vocalizations and audible aerial displays were detected at four locations using automated sound recording units (SM2+ Song Meters, Wildlife Acoustics) from June to August 2013-2014. We used two 5-minute recording segments for each hour, spaced 30 minutes apart, from at least one hour before sunset to at least one hour after sunrise. In 2013, we made a 5-minute recording every 30 minutes, while in 2014 we made a one-hour recording every hour and extracted two 5-minute segments from each recording for analysis. We developed a “recognizer” using Songscope software to automatically scan the 5-minute recording segments and detect “peent” calls. If at least one peent call was detected on a segment, then the spectrogram of that segment was visually scanned by a technician who counted occurrences of the “boom” sound, an audible flight display that is thought to be indicative of nesting territory. For every recording segment with peent calls detected, the previous and subsequent segments were also visually scanned by the technician and booms counted, even if no peent calls were detected by the Songscope recognizer on those recording segments. If the recognizer did not detect peent calls at a site for several nights, we did not scan subsequent recordings from that site. In total, 7296 5-minute recording segments were analysed.

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    The Rusty Blackbird (Euphagus carolinus) breeds in boreal forest wetlands across North America, and winters in the southeastern USA. This species is listed under Canada’s Species at Risk Act as Special Concern due to population declines. For the study, 1220 Rusty Blackbirds were captured in spring and fall from 2005-2010 at three sites in southern Yukon Territory (Whitehorse, Teslin, Watson Lake) in order to investigate timing of migration, stopover and molt, and to develop methods for age determination. We recorded sex, weight, wing length, fat, body molt, molt of primary and secondary wing feathers, eye colour, and extent of skull ossification. We photographed each bird (head, underwing, upperparts), and collected a primary feather (P1) for stable isotope analysis in order to determine breeding origin. Each bird was fitted with an aluminium band and a single colour band to indicate banding site. This dataset includes 717 individual Rusty Blackbirds captured at the Whitehorse Landfill site (60.751° -135.157°) by Canadian Wildlife Service personnel, plus 63 recaptures involving 57 of those 717 individuals. The other birds in the study (not included here) were captured in Teslin and Watson Lake, YT, by the Society of Yukon Bird Observatories http://www.yukonbirdobservatories.org/ . Basic banding data for all banded birds are also held by the Bird Banding Lab of Canadian Wildlife Service in Ottawa https://www.canada.ca/en/environment-climate-change/services/bird-banding.html