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1. Towns and trails drive carnivore movement behaviour, resource selection, and connectivity

   https://doi.org/10.1186/s40462-022-00318-5  

   Whittington, Jesse ; Hebblewhite, Mark ; Baron, Robin W. ; Ford, Adam T. ; Paczkowski, John ( December 2022 , Movement Ecology)

   Abstract Background Global increases in human activity threaten connectivity of animal habitat and populations. Protection and restoration of wildlife habitat and movement corridors require robust models to forecast the effects of human activity on movement behaviour, resource selection, and connectivity. Recent research suggests that animal resource selection and responses to human activity depend on their behavioural movement state, with increased tolerance for human activity in fast states of movement. Yet, few studies have incorporated state-dependent movement behaviour into analyses of Merriam connectivity, that is individual-based metrics of connectivity that incorporate landscape structure and movement behaviour. Methods We assessed the cumulative effects of anthropogenic development on multiple movement processes including movement behaviour, resource selection, and Merriam connectivity. We simulated movement paths using hidden Markov movement models and step selection functions to estimate habitat use and connectivity for three landscape scenarios: reference conditions with no anthropogenic development, current conditions, and future conditions with a simulated expansion of towns and recreational trails. Our analysis used 20 years of grizzly bear ( Ursus arctos ) and gray wolf ( Canis lupus ) movement data collected in and around Banff National Park, Canada. Results Carnivores increased their speed of travel near towns and areas of high trail and road density, presumably to avoid encounters with people. They exhibited stronger avoidance of anthropogenic development when foraging and resting compared to travelling and during the day compared to night. Wolves exhibited stronger avoidance of anthropogenic development than grizzly bears. Current development reduced the amount of high-quality habitat between two mountain towns by more than 35%. Habitat degradation constrained movement routes around towns and was most pronounced for foraging and resting behaviour. Current anthropogenic development reduced connectivity from reference conditions an average of 85%. Habitat quality and connectivity further declined under a future development scenario. Conclusions Our results highlight the cumulative effects of anthropogenic development on carnivore movement behaviour, habitat use, and connectivity. Our strong behaviour-specific responses to human activity suggest that conservation initiatives should consider how proposed developments and restoration actions would affect where animals travel and how they use the landscape. 

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2. Exploring the relationship between mobility and COVID− 19 infection rates for the second peak in the United States using phase-wise association

   https://doi.org/10.1186/s12889-021-11657-0  

   Gottumukkala, Raju ; Katragadda, Satya ; Bhupatiraju, Ravi Teja ; Kamal, Azmyin Md. ; Raghavan, Vijay ; Chu, Henry ; Kolluru, Ramesh ; Ashkar, Ziad ( December 2021 , BMC Public Health)

   Abstract Human mobility plays an important role in the dynamics of infectious disease spread. Evidence from the initial nationwide lockdowns for COVID− 19 indicates that restricting human mobility is an effective strategy to contain the spread. While a direct correlation was observed early on, it is not known how mobility impacted COVID− 19 infection growth rates once lockdowns are lifted, primarily due to modulation by other factors such as face masks, social distancing, and the non-linear patterns of both mobility and infection growth. This paper introduces a piece-wise approach to better explore the phase-wise association between state-level COVID− 19 incidence data and anonymized mobile phone data for various states in the United States. Prior literature analyzed the linear correlation between mobility and the number of cases during the early stages of the pandemic. However, it is important to capture the non-linear dynamics of case growth and mobility to be usable for both tracking and forecasting COVID− 19 infections, which is accomplished by the piece-wise approach. The associations between mobility and case growth rate varied widely for various phases of the epidemic curve when the stay-at-home orders were lifted. The mobility growth patterns had a strong positive association of 0.7 with the growth in the number of cases, with a lag of 5 to 7 weeks, for the fast-growth phase of the pandemic, for only 20 states that had a peak between July 1st and September 30, 2020. Overall though, mobility cannot be used to predict the rise in the number of cases after initial lockdowns have been lifted. Our analysis explores the gradual diminishing value of mobility associations in the later stage of the outbreak. Our analysis indicates that the relationship between mobility and the increase in the number of cases, once lockdowns have been lifted, is tenuous at best and there is no strong relationship between these signals. But we identify the remnants of the last associations in specific phases of the growth curve. 

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3. Swimming behaviors during diel vertical migration in veined squid Loligo forbesii

   https://doi.org/10.3354/meps14056  

   Cones, SF ; Zhang, D ; Shorter, KA ; Katija, K ; Mann, DA ; Jensen, FH ; Fontes, J ; Afonso, P ; Mooney, TA ( June 2022 , Marine Ecology Progress Series)

   Diel vertical migration (DVM) is a vital behavior for many pelagic marine fauna. Locomotory tactics that animals use during DVM define the metabolic costs of migrations and influence the risk of detection and capture by predators, yet, for squids, there is little understanding of the fine-scale movements and potential variability during these migrations. Vertical migratory behaviors of 5 veined squid Loligo forbesii were investigated with biologging tags (ITags) off the Azores Islands (central North Atlantic). Diel movements ranged from 400 to 5 m and were aligned with sunset and sunrise. During ascent periods, 2 squid exhibited cyclic climb-and-glide movements using primarily jet propulsion, while 3 squid ascended more continuously and at a lower vertical speed using mostly a finning gait. Descents for all 5 squid were consistently more rapid and direct. While all squid swam in both arms-first and mantle-first directions during DVM, mantle-first swimming was more common during upward movements, particularly at vertical speeds greater than 25 cm s -1 . The in situ variability of animal posture, swim direction, and gait use revealed behavioral flexibility interpreted as energy conservation, prey capture, and predator avoidance. 

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4. The impact of COVID-19 lockdowns on mental health patient populations in the United States

   https://doi.org/10.1038/s41598-024-55879-9  

   Ferwana, Ibtihal ; Varshney, Lav R. ( March 2024 , Scientific Reports)

   During the start of the COVID-19 pandemic in 2020, lockdowns and movement restrictions were thought to negatively impact population mental health, since depression and anxiety symptoms were frequently reported. This study investigates the effect of COVID-19 mitigation measures on mental health across the United States, at county and state levels using difference-in-differences analysis. It examines the effect on mental health facility usage and the prevalence of mental illnesses, drawing on large-scale medical claims data for mental health patients joined with publicly available state- and county-specific COVID-19 cases and lockdown information. For consistency, the main focus is on two types of social distancing policies, stay-at-home and school closure orders. Results show that lockdown has significantly and causally increased the usage of mental health facilities in regions with lockdowns in comparison to regions without such lockdowns. Particularly, resource usage increased by 18% in regions with a lockdown compared to 1% decline in regions without a lockdown. Also, female populations have been exposed to a larger lockdown effect on their mental health. Diagnosis ofpanic disordersandreaction to severe stresssignificantly increased by the lockdown. Mental health was more sensitive to lockdowns than to the presence of the pandemic itself. The effects of the lockdown increased over an extended time to the end of December 2020.

    

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5. Movement rules determine nomadic species' responses to resource supplementation and degradation

   https://doi.org/10.1111/1365-2656.13318  

   Teitelbaum, Claire S. ; Altizer, Sonia ; Hall, Richard J. ; Börger, ed., Luca ( September 2020 , Journal of Animal Ecology)

   In environments that vary unpredictably, many animals are nomadic, moving in an irregular pattern that differs from year to year. Exploring the mechanisms of nomadic movement is needed to understand how animals survive in highly variable environments, and to predict behavioural and population responses to environmental change.

   We developed a network model to identify plausible mechanisms of nomadic animal movement by comparing the performance of multiple movement rules along a continuum from nomadism to residency. Using simulations and analytical results, we explored how different types of habitat modifications (that augment or decrease resource availability) might affect the abundance and movement rates of animals following each of these rules.

   Movement rules for which departure from patches depended on resource availability and/or competition performed almost equally well and better than residency or uninformed movement under most conditions, even though animals using each rule moved at substantially different rates. Habitat modifications that stabilized resources, either by resource supplementation or degradation, eroded the benefits of informed nomadic movements, particularly for movements based on resource availability alone.

   These results suggest that simple movement rules can explain nomadic animal movements and determine species’ responses to environmental change. In particular, landscape stabilization and supplementation might be useful strategies for promoting populations of resident animals, but would be less beneficial for managing highly mobile species, many of which are threatened by habitat disruption and changes in climate.

    

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