Junior Tremblay

• PhD
• Researcher at Environment Canada, Quebec City

We investigated the breeding habitat selection of the Canada Warbler (Cardellina canadensis) in southern Quebec across three distinct landscapes: a mixed boreal forest, an agroforestry landscape, and a riverine deciduous forest. This study aimed to characterize breeding habitat by assessing fine-scale vegetation structure and composition at surveye...

BirdNET is a popular machine learning tool for automated recognition of bird sounds. Here we evaluate how BirdNET settings affect the model performance both at vocalization and species levels, using 4,225 one-minute recordings from 67 recording locations worldwide. Giving equal importance to recall and precision, a low confidence score threshold (0...

Aim The urgency for remote, reliable and scalable biodiversity monitoring amidst mounting human pressures on ecosystems has sparked worldwide interest in Passive Acoustic Monitoring (PAM), which can track life underwater and on land. However, we lack a unified methodology to report this sampling effort and a comprehensive overview of PAM coverage t...

Under the current global biodiversity crisis, there is a need for automated and non-invasive monitoring techniques that are able to gather large amounts of information cost-effectively at large scales. One such technique is passive acoustic monitoring, which is commonly coupled with automatic identification of animal species based on their sound. A...

Bird populations within the same species may follow different migratory strategies and phenology depending on their breeding location and latitude, and migratory strategies may be influenced by important stopover sites. Understanding these strategies and identifying important stopover sites is crucial for the conservation of species with regionally...

Identifying the drivers of population declines in migratory species requires an understanding of how individuals are distributed between periods of the annual cycle. We built post- (fall) and pre-breeding (spring) migratory networks for the blackpoll warbler (Setophaga striata), a Neotropical-Nearctic songbird, using tracking data from 47 light-lev...

La saison des feux de forêt de 2023 au Québec, marquée par des conditions extrêmement chaudes et sèches, a établi de nouveaux records en brûlant 4,5 millions d'hectares. Cette situation est directement liée aux impacts persistants et en augmentation du changement climatique. Cette étude examine les conditions météorologiques exceptionnelles ayant m...

The border between Canada and the United States poses jurisdictional challenges when it comes to consistently implementing science-based conservation of forests and their biological communities. Through a partnership with the Sustainable Forestry Initiative, Boreal Avian Modelling Project, and American Bird Conservancy, we developed a co-production...

The 2023 wildfire season in Québec set records due to extreme warm and dry conditions, burning 4.5 million hectares and indicating persistent and escalating impacts associated with climate change. This study reviews the unusual weather conditions that led to the fires, discussing their extensive impacts on the forest sector, fire management, boreal...

The combination of climate change and anthropogenic disturbance significantly impacts forest bird assemblages. Assessing the cumulative effects of forest management and climate change on biodiversity and ecosystem services, including carbon sequestration and storage and provisioning of wood products is key to informing forest management and conserv...

The need for remote, reliable, and scalable monitoring of plummeting biodiversity amidst mounting human pressures on ecosystems and changing climate has sparked enormous interest in Passive Acoustic Monitoring (PAM) over multiple disciplines and ecosystems. Even though PAM could support UN Sustainable Development Goals and the Global Biodiversity I...

The 2023 wildfire season in Québec set records due to extreme warm and dry conditions, burning 4.5 million hectares and indicating persistent and escalating impacts associated with climate change. The study reviews the unusual weather conditions that led to the fires, discussing their extensive impacts on the forest sector, fire management, boreal...

To recover species at risk, it is necessary to identify habitat critical to their recovery. Challenges for species with large ranges (thousands of square kilometres) include delineating management unit boundaries within which habitat use differs from other units, along with assessing any differences among units in amounts of and threats to habitat...

The migration phenology of many bird species has changed over the past few decades, but whether such changes lead to changes in the nesting phenology remains little known. Studying bird nesting in the boreal forest comes with challenges because of the large size of this biome. We evaluated songbird nesting phenology for the past 25 yrs in a boreal...

A tree-related microhabitat (abbreviated as TreM) is a morphological feature present on a tree, which is used by sometimes highly specialised species during at least one part of their life cycle. These features may serve as shelters, breeding spots, or crucial hibernation or feeding places for thousands of species. Each TreM provides very specific...

Identifying genetic conservation units (CUs) in threatened species is critical for the preservation of adaptive capacity and evolutionary potential in the face of climate change. However, delineating CUs in highly mobile species remains a challenge due to high rates of gene flow and genetic signatures of isolation by distance. Even when CUs are del...

The relationship between species presence, biodiversity reconstruction, and latitudinal gradients is a complex and multifaceted topic that has been the subject of extensive research in ecology. Recent studies have provided valuable insights into the patterns and drivers of these phenomena. Also, with the ongoing decline in biodiversity, there is a...

Identifying genetic conservation units (CUs) in threatened species is critical for the preservation of adaptive capacity and evolutionary potential in the face of climate change. However, delineating CUs in highly mobile species remains a challenge due to high rates of gene flow and genetic signatures of isolation by distance. Even when CUs are del...

Knowledge on the diet of the Black-backed Woodpecker (Picoides arcticus Swainson, 1832) is fragmentary and relies on a limited number of studies. Gaps remain in our understanding of the plasticity of its diet, particularly in the eastern part of its range. The main objective of this study was to assess the diet of Black-backed Woodpeckers in burned...

Background Each spring and fall billions of songbirds depart on nocturnal migrations across the globe. Theory suggests that songbirds should depart on migration shortly after sunset to maximize their potential for nightly flight duration or to time departure with the emergence of celestial cues needed for orientation and navigation. Although captiv...

Background Weather can have both delayed and immediate impacts on animal populations, and species have evolved behavioral adaptions to respond to weather conditions. Weather has long been hypothesized to affect the timing and intensity of avian migration, and radar studies have demonstrated strong correlations between weather and broad-scale migrat...

Regional analyses assessing the vulnerabilities of forest ecosystems and the forest sector to climate change are key to considering the heterogeneity of climate change impacts as well as the fact that risks, opportunities, and adaptation capacities might differ regionally. Here we provide the Regional Integrated Assessment of climate change on Queb...

To recover species at risk, it is necessary to identify habitat critical to their recovery. Challenges for species with large ranges (thousands of square kilometres) include delineating management unit boundaries within which habitat use differs from other units, along with assessing amounts of and threats to habitat over time. We developed a repro...

Deadwood is a key component for biodiversity and ecosystem services inboreal forests; however, the abundance of this critical element is declining worldwide.In natural forests, deadwood is produced by tree death due to physical disturbances,senescence, or pathogens. Timber harvesting, fire suppression, and salvage loggingreduce deadwood abundance a...

Logging is the main human disturbance impacting biodiversity in forest ecosystems. However, the impact of forest harvesting on biodiversity is modulated by abiotic conditions through complex relationships that remain poorly documented. Therefore, the interplay between forest management and climate change can no longer be ignored. Our aim was to stu...

Conservation approaches that efficiently protect multiple values, such as the umbrella species concept, have been widely promoted with expected dramatic ecosystem changes. Due to its social and cultural importance, and recent declining trends, boreal populations of woodland caribou have been suggested as potential umbrella species for other declini...

Most research on boreal populations of woodland caribou (Rangifer tarandus caribou) has been conducted in areas of high anthropogenic disturbance. However, a large portion of the species' range overlaps relatively pristine areas primarily affected by natural disturbances, such as wildfire. Climate‐driven habitat change is a key concern for the cons...

Coastlines in marine areas are known to influence use of the airspace as a habitat by migrating birds, but less is known about how the complex configuration of the Great Lakes influences bird migration patterns. If birds alter their migration in response to the lakes, they may become concentrated in specific areas, which should receive particular a...

Habitat changes due to human exploitation of natural resources impact ecosystems worldwide, notably by causing pronounced changes in abiotic and biotic conditions, which modify biological diversity at the taxonomic, phylogenetic, and functional levels. In forest ecosystems, logging is the main human disturbance impacting biodiversity. The interplay...

The study of migratory songbird transition periods, such as the post-breeding period, is complex because birds undertake different types of movements that vary in space and time. Nonetheless, it is important to understand the extent and duration of the territory and specific sites use to identify human activities likely to affect the species’ survi...

Distributions of landbirds in Canadian northern forests are expected to be affected by climate change, but it remains unclear which pathways are responsible for projected climate effects. Determining whether climate change acts indirectly through changing fire regimes and/or vegetation dynamics, or directly through changes in climatic suitability m...

Williamson’s Sapsuckers, like most woodpeckers, require live and dead standing trees for foraging and nesting. Forest management plans that include Williamson’s Sapsucker habitat conservation guidelines currently focus on nesting trees because little is known about foraging habitat requirements, but foraging habitat in close proximity is also essen...

This is an animation of fall migratory movements of Swainson's Thrushes from Eastern Canada as detected by Motus. Original paper can be accessed here: https://rdcu.be/clWDu

Old‐growth forests are optimal habitats for many woodpeckers, which are often themselves excellent indicators of deadwood‐associated biodiversity. Old‐growth forests are, however, heterogeneous ecosystems in terms of structure, composition, and deadwood characteristics, thus implying a varied use of these forests by woodpeckers. In boreal landscape...

Background Migratory connectivity links the different populations across the full cycle and across the species range and may lead to differences in survival among populations. Studies on spatial and temporal migratory connectivity along migration routes are rare, especially for small migratory animals. Methods We used an automated radio-telemetry...

Many migratory species are declining and for most, the proximate causes of their declines remain unknown. For many long-distance Neotropical migratory songbirds, it is assumed that habitat loss on breeding or non-breeding grounds is a primary driver of population declines. We integrated data collected from tracking technology, community science and...

Migratory connectivity is the degree to which populations are linked in space and time across the annual cycle. Low connectivity indicates mixing of populations while high connectivity indicates population separation in space or time. High migratory connectivity makes individual populations susceptible to local environmental conditions; therefore,...

The southern extent of the boreal forest in North America has experienced intensive human disturbance in recent decades. Among these, forest harvesting leads to the substantial loss of late-successional stands that include key habitat attributes for several avian species. The American Three-toed Woodpecker, Picoides dorsalis, is associated with con...

The southern extent of the boreal forest in North America has experienced intensive human disturbance in the past decades. Among these, forest harvesting leads to the substantial loss of late-successional stands that include key habitat attributes for several avian species. The American Three-toed Woodpecker, Picoides dorsalis, is associated with c...

Background To effectively conserve migratory species, the entire range encompassed by their annual life cycle needs to be considered. Most research on Nearctic-Neotropical migratory birds has focused on the breeding grounds resulting in a general lack of knowledge regarding the wintering and migratory periods. The Canada Warbler (Cardellina canaden...

Predicting and mitigating impacts of climate change and development within the boreal biome requires a sound understanding of factors influencing the abundance, distribution, and population dynamics of species inhabiting this vast biome. Unfortunately, the limited accessibility of the boreal biome has resulted in sparse and spatially biased samplin...

Standing deadwood is an important attribute of old-growth boreal forests and it provides essential microhabitats for deadwood-associated species. In managed boreal forests, short rotations tend to limit the amount and diversity of standing deadwood. This study evaluates if the anthropogenic supply of deadwood attributes through tree girdling or by...

Aim Climate change is expected to influence boreal bird communities significantly, notably through changes in forest habitat (composition and age structure), in the coming decades. How these changes will accumulate and interact with anthropogenic disturbances remains an open question for most species. Location Northeastern Alberta, Canada. Method...

Migration routes vary greatly among small passerine species and populations. It is now possible to determine the routes over great distances and long periods of time with emerging monitoring networks. We tracked individual Swainson’s Thrush ( Catharus ustulatus ), Bicknell’s Thrush ( Catharus bicknelli ) and Gray-cheeked Thrush ( Catharus minimus )...

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 qu...

The boreal forests of North America support billions of birds of over 300 species. The region remains mostly intact but is expected to undergo major changes over the next century due to anthropogenic climate change. This warming, and resulting changes in moisture regimes, are altering vegetation and disturbance dynamics, and will likely result in e...

Forest harvesting reduces mean stand age and dead wood amount. Among species dependent upon older forests and dead wood, primary excavators such as woodpeckers play an important ecological role by providing cavities for many other species. Conservation of these species thus requires striking a balance between timber harvesting and dead wood supply,...

With climate change, natural resource managers are faced with the challenging task of planning the conservation of habitat for threatened species. Classified as "threatened" under the Species at Risk Act in Canada, the Bicknell's Thrush (Catharus Bicknelli - BITH) is a migratory bird whose range is highly restricted. Bioclimatic models project more...

Recent studies have demonstrated the high potential of drones as tools to facilitate wildlife radio-tracking in rugged, difficult-to-access terrain. Without estimates of accuracy, however, data obtained from receivers attached to drones will be of limited use. We estimated transmitter location errors from a drone-borne VHF (very high frequency) rec...

Williamson's Sapsuckers (Sphyrapicus thyroideus) are montane woodpeckers threatened by widespread tree removal activities and climate change. Current forest management plans focus on nesting trees, but the incorporation of foraging trees would lead to a more effective management strategy to mitigate habitat loss for this species. We investigated th...

Red Crossbill percna (e.g. Type 8) is considered a distinctive taxonomic group likely restricted to the island of Newfoundland. While it has been speculated that the percna subspecies may be extinct, recent works continue to show that Red Crossbills from insular Newfoundland are morphologically and vocally distinct. Large-billed Red Crossbills that...

Many studies project future bird ranges by relying on correlative species distribution models. Such models do not usually represent important processes explicitly related to climate change and harvesting, which limits their potential for predicting and understanding the future of boreal bird assemblages at the landscape scale. In this study, we att...

Le moucherolle à côtés olive ( Contopus cooperi ) a subi un important déclin depuis la fin des années 1960. La mise en place de mesures visant à favoriser son rétablissement est par contre limitée par notre manque de connaissances sur l’écologie de la nidification de l’espèce. L’objectif de cette étude était d’acquérir des connaissances sur le succ...

Recent advances in using Unmanned Aerial Vehicles (UAV) to study wildlife offer promise and may improve data collection efficiency, and small UAVs such as multirotor platforms are suitable for this task because they are easy to deploy, can fly over terrain that is difficult to access on foot, and can be programmed to follow specific trajectories. T...

Preliminary results

Nest care is an important parental contribution to offspring. In woodpeckers, males often have an equal or greater contribution to parental care, including nest sanitation. The Black-backed Woodpecker (Picoides arcticus) is a North American boreal woodpecker for which both parents are highly involved in parental care. By modifying their territory s...

Black-backed woodpecker is known to be a disturbance-associated species, being more abundant in disturbed forest stands than in undisturbed habitats, but its demography and population dynamic still need to be clarified. The present study was conducted in central Quebec within coniferous forests shaped largely by timber harvest and wildfire. The obj...

Large birds regularly use updrafts to subsidize flight. Although most research on soaring bird flight has focused on use of thermal updrafts, there is evidence suggesting that many species are likely to use multiple modes of subsidy. We tested the degree to which a large soaring species uses multiple modes of subsidy to provide insights into the de...

Migration is costly in terms of time, energy and safety. Optimal migration theory suggests that individual migratory birds will choose between these three costs depending on their motivation and available resources. To test hypotheses about use of migratory strategies by large soaring birds, we used GPS telemetry to track 18 adult, 13 sub-adult and...

Climate change is thought to strongly alter boreal forest processes, vegetation composition and age structure. As such, bird habitats should greatly change, triggering potential range shift in bird species. Most of studies projecting future bird habitats rely on species distribution models (SDM) which are mainly based on projections of where climat...

Aquila chrysaetos (Golden Eagle) breeds in both eastern and western North America. However, the former population has received much less attention than the latter. The purpose of this paper is to document the known distribution and abundance of eastern Golden Eagles within their breeding range and to identify gaps in knowledge for future studies. E...

The province of Québec has considerable potential for the continued expansion of its wind power industry. Wind farms may be a cause of mortality for birds of prey and could have a particularly negative affect on certain vulnerable species, such as the peregrine falcon. To help determine the types of sites to favour for the establishment of new wind...