Understanding how bird populations are spatially structured throughout their annual cycles is critical to identifying when and where these populations are most limited. Canadian breeding populations of Horned Grebe (Podiceps auritus cornutus; hereafter grebe) appear to have substantially declined since 1970, and uncertainty in annual movements of this species limits our understanding of factors affecting their population dynamics. To address this knowledge gap and identify grebes’ migration routes and non-breeding areas, we fit light-level geolocators and sampled feathers for stable isotopes (carbon δ13C, nitrogen δ15N, hydrogen δ2H) in Prairie and Boreal portions of the grebe breeding range between 2020 and 2023. Geolocator data (n = 18 birds) indicated that grebes undertook southeastern fall migratory movements and occupied marine and freshwater non-breeding locations across a large geographic area including southeastern Canada, the Midwest and southern United States, the Atlantic Coast, and the Gulf of Mexico. Geolocator and feather stable isotope data confirmed weak migratory connectivity and separated birds into four distinct non-breeding ground clusters. Our results suggest threats that grebes experience on non-breeding areas may have diffuse effects on breeding populations and further provide novel information on the migration ecology and spatial linkages of two breeding populations of grebes in North America. Taken together, these findings will help to inform development and implementation of management strategies for this species of conservation concern.

Municipalities with established populations of _Ixodes scapularis_ ticks (blacklegged ticks) are municipalities where tick populations reproduce and survive from one year to the next. This indicator makes it possible to identify municipalities where their presence suggests a higher risk of tick bites and the transmission of diseases, such as Lyme disease, anaplasmosis or babesiosis. In other municipalities without an established population, the presence of ticks is possible, as ticks can be carried there by birds or terrestrial mammals. The data used to build this indicator come from passive and active acarological surveillance. Active and passive surveillance data were accumulated and then aggregated by municipality and by year. This made it possible to determine whether an established tick population is identified by the indicator at least 1 year over the study period. The climate zone favorable to the establishment of ticks _Ixodes scapularis_ highlights the areas where the estimated temperature would be favorable to the establishment of tick populations in Quebec. An area where the climate is favorable for the establishment of tick populations is defined by an annual number of degree-days above 0°C (DJ0). This indicator was calculated for the historical surveys 2009-2017 (current distribution) and for the horizons of 2030, 2050 and 2080 according to the climate scenarios SSP2-4.5 and SSP3-7.0 (future distribution). The DJ0 are calculated by calculating the difference between the daily mean temperature and the 0°C reference temperature used in this situation, then interpolating on a 10km x 10km grid. The final DJ0 value used is the 50th percentile. For more information on municipalities with established populations of _Ixodes scapularis_ ticks or the climatic zones favorable to their establishment you can consult the * [Methodological Report] ( https://www.inspq.qc.ca/publications/3483) * OR the * [INSPQ website, Current and future distribution maps of zoonoses in Quebec] (https://www.inspq.qc.ca/zoonoses/cartes) *.**This third party metadata element was translated using an automated translation tool (Amazon Translate).**

The West Nile virus (WNV) activity zone corresponds to the territory where WNV cases have been documented by human, animal, and entomological (mosquito) surveillance. This zone indicates where there is a higher probability of the virus being present in Quebec based on historical data. All surveillance data was aggregated to form the WNV's area of activity over the study period, by merging the 2 km resolution buffer zones and the municipalities of each mosquito case or batch. Outside of this area, the presence of WNV remains possible, but the virus has not been detected by surveillance. This can be explained, among other things, by the movements of infected birds and mosquitoes over varying distances. The climatic zone favorable to the transmission of WNV by Culex pipiens (one of the main vectors of the virus) highlights the territory where the estimated seasonal average temperature could be conducive to the transmission of WNV in Quebec. This zone is defined by a seasonal average temperature (calculated from April to September) greater than or equal to 14°C. The indicator was calculated for historical records 1989-2018 (current distribution) and for the horizons of 2030, 2050 and 2080 according to the greenhouse gas emissions scenarios SSP2-4.5 and SSP3-7.0 (future distribution). Seasonal mean temperatures were calculated during the WNV's active period (i.e. April to September) by adding up the daily maximum and minimum temperatures and then dividing them by two. These temperatures were generated with a resolution of 10 km x 10 km covering the whole of Quebec for time horizons and greenhouse gas emission scenarios. The final value for seasonal mean temperatures used is the 50th percentile. For more information on the area of activity of the WNV or the climatic zones favorable to the transmission of WNV by Culex pipiens, you can consult the [Mapping of the current and future distribution of the West Nile virus in Quebec in the context of climate change] (https://www.inspq.qc.ca/publications/3693) OR the INSPQ website [Current and future distribution maps of zoonoses in Quebec] (https://www.inspq.qc.ca/zoonoses/cartes).**This third party metadata element was translated using an automated translation tool (Amazon Translate).**

The Chemicals Management Plan (CMP) Wildlife Monitoring and Surveillance Program is a long-established federal initiative that evaluates contaminant exposure in terrestrial and aquatic-associated wildlife across Canada. Biological samples, collected throughout the years from various locations nationwide, are preserved in long-term specimen banks under controlled conditions. These stored samples support retrospective analyses and ongoing research funded by federally mandated programs, such as the Great Lakes Water Quality Agreement (GLWQA) and the CMP. Specimens are analyzed for a wide range of chemicals of concern under these programs, including trace metals, polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), and per- and polyfluoroalkyl substances (PFAS).

The Wildlife Contaminants Monitoring and Surveillance Program assesses contaminant exposure in aquatic-associated wildlife across Canada. Biological samples, including eggs and tissues, are collected from gull sentinel species, (such as California gulls, herring gulls, and glaucous-winged gulls) and serve as integrators of contaminant exposure across aquatic food webs. This monitoring focuses on large aquatic systems nationwide, including the Great Lakes and coastal environments, to evaluate spatial and temporal trends in contaminant levels.

The Wildlife Contaminants Monitoring and Surveillance Program assesses contaminant exposure in terrestrial wildlife across Canada. Biological samples, including eggs and tissues, from the sentinel species European starlings are collected and provide a complementary perspective on contaminant exposure in terrestrial and urban-associated ecosystems. This monitoring evaluates spatial and temporal trends in contaminant levels within these environments.