Species Abundance Modelling of Arctic-Boreal Zone Ducks Informed by Satellite Remote Sensing

The Arctic-Boreal zone (ABZ) covers over 26 million km2 and is home to numerous duck species; however, understanding the spatiotemporal distribution of their populations across this vast landscape is challenging, in part due to extent and data scarcity. Species abundance models for ducks in the ABZ commonly use static (time invariant) habitat covariates to inform predictions, such as wetland type and extent maps. For the first time in this region, we developed species abundance models using high-resolution, time-varying wetland inundation data produced using satellite remote sensing methods. This data captured metrics of surface water extent and inundated vegetation in the Peace Athabasca Delta, Canada, which is within the NASA Arctic Boreal Vulnerability Experiment core domain. We used generalized additive mixed models to demonstrate the improved predictive value of this novel data set over time-invariant data. Our findings highlight both the potential complementarity and efficacy of dynamic wetland inundation information for improving estimation of duck abundance and distribution at high latitudes. Further, these data can be an asset to spatial targeting of biodiversity conservation efforts and developing model-based metrics of their success under rapidly changing climatic conditions

Comparative reproductive parameters of sympatric Lesser Scaup (Aythya affinis) and Ring-necked Duck (Aythya collaris) in parkland Manitoba

Waterfowl managers are concerned that Lesser Scaup (Aythya affinis) breeding populations remain below conservation goals. Contrasting population growth trajectories for sympatric, phylogenetically similar Lesser Scaup and Ring-necked Duck (Aythya collaris) at Erickson, Manitoba, Canada, prompted investigations that might help explain these trends and provide insight for population management of both species. We collected data (2008–2018) on productivity (broods/pair), water levels, hatching dates, age class-specific brood sizes, duckling daily survival rate, and brood female response to disturbance and compared results between species over time. Ring-necked Duck productivity was greater (0.42 versus 0.28, P < 0.01), hatching dates were earlier (19 July versus 27 July, P < 0.001), and females attempted to hide their broods more often than did Lesser Scaup (16% versus 3%, P < 0.001), but Ring-necked Duck age class-specific brood sizes were smaller than for Lesser Scaup (Ia broods: 6.1 versus 6.8, P = 0.02; IIa broods: 5.6 versus 6.2, P = 0.02). Duckling daily survival rates were similar. Productivity of both species was positively related to annual change in pond water level and both demonstrated similar rates of response to change. There was no support for an association between productivity and one- or two-year lagged pond water levels. Consistent with previous findings, our results suggest that greater Ring-necked Duck productivity is a likely proximate cause for the differing population growth trajectories between the species. We suggest that better Ring-necked Duck nest placement may be a contributing factor to the greater nest success observed

Mallard Brood Movements in the Canadian Prairie Parklands

We radiotracked 308 mallard (Anas platyrhynchos) broods from hatching until 30 days of age Oij 15 study areas located throughout the Canadian Prairie Parklands to examine patterns of variation in movement frequency and distance. Broods moved an average of 350 m from nests to first wetlands (SO = 390), with 94% of broods moving less than I km. After leaving the nest, broods had a 23% probability of moving to a new wetland each day, but movement probability was a complex function of study area, hatch date, and ducking age, with younger and earlier-hatched broods exhibiting greater movement rates than older and later-hatched broods. Later-hatched broods moved farther than earlierhatched broods and movement distance also varied among study areas. Local wetland characteristics explained some of the among-site variation in movement rates and distances, with movement probability being most strongly correlated with average size of semipermanent wetlands and movement distance being most strongly correlated with total acreage of seasonal wetlands. After 30 days, broods were located an average of 760 m (SO = 610) from their nests, with 95% of all surviving broods located less than 2 km from their nests. Our data illustrated the need for suitable brood-rearing wetlands within a reasonable distance (e.g., \u3c 0.5 km) of waterfowl nesting cover

Assessing breeding duck population trends relative to anthropogenic disturbances across the boreal plains of Canada, 1960-2007

Impacts of anthropogenic disturbance on duck populations in the boreal forest is largely unknown but hypothesized to negatively influence abundance through top-down and bottom-up processes. We examined relationships between population trajectory of duck pairs and anthropogenic disturbances in the Boreal Plains ecozone of western Canada by first controlling for habitat and then assessing whether population trends were related to density of seismic lines, pipelines, roads, and well sites, and distance to agriculture to help focus conservation efforts on the most limiting changes. We also evaluated whether these relationships differed in agriculture encroached vs. unencroached landscapes; distance to agriculture was assessed in unencroached landscapes. Pair counts (1960-2007) obtained from the Waterfowl Breeding Population and Habitat Survey were pooled into nesting guilds (cavity, ground, and overwater). All anthropogenic disturbance features were time invariant. Annual moisture data was used to control for effects of annual variation in breeding season weather. Variation in relative magnitude and direction of effect size indices among anthropogenic disturbances depended on both landscape and nesting guild. Overall, majority of negative relationships occurred with seismic lines and pipelines, while distance to agriculture was positive. Population trends for ground nesters, which suggest overall declines, tended be most negative in regions with high seismic line and well pad density in encroached landscapes and with high seismic line and pipeline density in unencroached landscapes. Cavity nester population trends were generally positive throughout the study area but were lowest in unencroached landscapes farthest from agriculture. Overwater nester trends were generally lowest in encroached landscapes with high densities of seismic lines, roads, and well pads and in unencroached landscapes with high densities of seismic lines, pipelines, and roads. Although our work suggests that anthropogenic disturbances, particularly seismic and pipelines, may merit further consideration as foci for conservation, additional research is needed to quantify demographic implications

Heterogeneous Changes to Wetlands in the Canadian Prairies Under Future Climate

Author Posting. © American Geophysical Union, 2021. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Water Resources Research 57(7), (2021): e2020WR028727, https://doi.org/10.1029/2020WR028727.Numerous wetlands in the prairies of Canada provide important ecosystem services, yet are threatened by climate and land-use changes. Understanding the impacts of climate change on prairie wetlands is critical to effective conservation planning. In this study, we construct a wetland model with surface water balance and ecoregions to project future distribution of wetlands. The climatic conditions downscaled from the Weather Research and Forecasting model were used to drive the Noah-MP land surface model to obtain surface water balance. The climate change perturbation is derived from an ensemble of general circulation models using the pseudo global warming method, under the RCP8.5 emission scenario by the end of 21st century. The results show that climate change impacts on wetland extent are spatiotemporally heterogenous. Future wetter climate in the western Prairies will favor increased wetland abundance in both spring and summer. In the eastern Prairies, particularly in the mixed grassland and mid-boreal upland, wetland areas will increase in spring but experience enhanced declines in summer due to strong evapotranspiration. When these effects of climate change are considered in light of historical drainage, they suggest a need for diverse conservation and restoration strategies. For the mixed grassland in the western Canadian Prairies, wetland restoration will be favorable, while the highly drained eastern Prairies will be challenged by the intensified hydrological cycle. The outcomes of this study will be useful to conservation agencies to ensure that current investments will continue to provide good conservation returns in the future.Z. Zhang was funded by a Mitacs Accelerate Fellowship funded by Ducks Unlimited Canada's Institute for Wetland and Waterfowl Research. Z. Zhang, Z. Li, and Y. Li acknowledge the financial support from the Natural Sciences and Engineering Research Council of Canada (NSERC) Discovery Grant, and Global Water Futures Program, Canada First Research Excellence Fund. This project was supported by grants from Wildlife Habitat Canada, Bass Pro Shops Cabela’s Outdoor Fund, and the Alberta NAWMP Partnership.2021-12-2