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Roads can result in negative effects on wildlife including habitat loss, behavioral avoidance, reduced survival, reproduction and gene flow. These road effects are especially pronounced for large mammals given their large home‐range requirements and low reproductive rates. To counteract these negative effects, road mitigation measures, such as underpasses and overpasses, are promoted; however, future landscape changes are rarely considered when selecting mitigation locations. We used GPS telemetry data on female American black bears Ursus americanus to examine their response to roads in Massachusetts, US. We compared bear road crossing frequency with a null crossing model derived from a correlated random walk, estimated road crossing movement speeds, and fit a road‐crossing resource selection function. We found that, though black bears crossed roads less than expected based on the null model, 10% of their observed steps, on average, crossed roads. We also found bears crossed roads at higher movement speeds than during other home‐range behaviors, and that bears preferred to cross smaller, less trafficked roads in areas with lower speed limits, less human development and more forest. We used the resource selection model to identify road segments for potential mitigation efforts and then used future human development projections to forecast future changes in these segments. We found a decrease of 15% in the length of suitable mitigation segments from 2019 to 2050. Given the sizeable investment in wildlife crossing structures and their longevity on the landscape, we recommend incorporating future projections into crossing site selection to ensure the long‐term viability of road mitigation efforts. [ABSTRACT FROM AUTHOR]

COVID-19 lockdowns in early 2020 reduced human mobility, providing an opportunity to disentangle its effects on animals from those of landscape modifications. Using GPS data, we compared movements and road avoidance of 2300 terrestrial mammals (43 species) during the lockdowns to the same period in 2019. Individual responses were variable with no change in average movements or road avoidance behavior, likely due to variable lockdown conditions. However, under strict lockdowns 10-day 95th percentile displacements increased by 73%, suggesting increased landscape permeability. Animals' 1-hour 95th percentile displacements declined by 12% and animals were 36% closer to roads in areas of high human footprint, indicating reduced avoidance during lockdowns. Overall, lockdowns rapidly altered some spatial behaviors, highlighting variable but substantial impacts of human mobility on wildlife worldwide.

Background: With the growth and expansion of human development, large mammals will increasingly encounter humans, elevating the likelihood of human-wildlife conflicts. Understanding the behavior and movement of large mammals, particularly around human development, is important for crafting effective conservation and management plans for these species., Methods: We used GPS collar data from American black bears ( Ursus americanus ) to determine how seasonal food resources and human development affected bear movement patterns and resource use across the Commonwealth of Massachusetts., Results: We found that though bears moved more and avoided human development during crepuscular and daylight hours than at night, bears preferentially moved through human dominated areas at night. This indicates bears were mitigating the risk of human development by altering their behavior to exploit these areas when human activity is low. This behavioral shift was most prominent in the spring, when natural foods are scarce, and fall, when energetic demands are high. We also observed a high degree of inter-individual variability among our sample of bears. Bears with a higher density of houses in their home ranges (~ 75 houses/km2) displayed less avoidance of human development than more rural bears. Furthermore, bear movement models had different explanatory variables, with preference or avoidance of a variable being dependent on the individual bear. To account for this individuality in our predictive surfaces, we projected the probability of movement for each season and time of day using a spatially weighted surface centered on each bear's home range., Conclusions: We found that black bears in Massachusetts are operating in a landscape of fear and are altering their movement patterns to use developed areas when human activity is low. We also found seasonal and diel differences among individual bears in resource selection during movement. Accounting for these individual, seasonal, and diel differences when assessing movement for large mammals is especially important if predictive surfaces are to be used in identifying areas for conservation and management., Competing Interests: Competing interestsThe authors declare that they have no competing interests.