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The article focuses on migration of ungulates (hooved mammals) which is fundamental ecological process that promotes abundant herds, and effects cascade up and down terrestrial food web. It mentions migratory ungulates provide the prey base that maintains large carnivore and scavenger populations and underpins terrestrial biodiversity. It also mentions climate change poses an additional threat and designed to support conservation action and policy at local, national, and international levels.

Fine‐scale movement data has transformed our knowledge of ungulate migration ecology and now provides accurate, spatially explicit maps of migratory routes that can inform planning and management at local, state, and federal levels. Among the most challenging land use planning issues has been developing energy resources on public lands that overlap with important ungulate habitat, including the migratory routes of mule deer (Odocoileus hemionus). We generally know that less development is better for minimizing negative effects and maintaining habitat function, but we lack information on the amount of disturbance that animals can tolerate before reducing use of or abandoning migratory habitat. We used global positioning system data from 56 deer across 15 years to evaluate how surface disturbance from natural gas well pads and access roads in western Wyoming, USA, affected habitat selection of mule deer during migration and whether any disturbance threshold(s) existed beyond which use of migratory habitat declined. We used resource and step selection functions to examine disturbance thresholds at 3 different spatial scales. Overall, migratory use by mule deer declined as surface disturbance increased. Based on the weight of evidence from our 3 independent but complementary metrics, declines in migratory use related to surface disturbance were non‐linear, where migratory use sharply declined when surface disturbance from energy development exceeded 3%. Disturbance thresholds may vary across regions, species, or migratory habitats (e.g., stopover sites). Such information can help with management and land use decisions related to mineral leasing and energy development that overlap with the migratory routes of ungulates. © 2020 The Wildlife Society. Mule deer were sensitive to energy development during migration and migratory use declined when surface disturbance exceeded 3%. Better understanding the relationship between surface disturbance and migratory behavior can help identify tradeoffs and potential mitigation measures associated with mineral leasing and energy development that overlap with the migratory routes of ungulates. [ABSTRACT FROM AUTHOR]

Increasing habitat fragmentation and disturbance threaten long-distance movements of ungulates. While the effects of impermeable barriers on ungulate migrations have been well researched, quantitative evidence for gradual, long-term changes of mobility remains rare. We investigated changes in movement behavior of Mongolian gazelle Procapra gutturosa using GPS tracking data collected from 62 gazelle individuals between 2007 and 2021. We quantified 16-day displacement distances as a metric for long-distance movements before using linear mixed models, generalized additive models and quantile regressions to assess how anthropogenic and environmental factors affected gazelle movement behavior. Long-distance 16-day movements decreased by 36 %, from 142 km in 2007 to 92 km in 2021. Changes in mobility were affected by increasing vehicle numbers in Mongolia, but could not be explained by concurrent changes in other environmental factors like temperature, precipitation or vegetation greenness. Gazelle movement decreased close to roads, and gazelles stayed further away from roads during the snow-free season, when traffic likely is most intense. Conserving landscape permeability is essential for maintaining populations of highly mobile species. Our study provides evidence for a gradual decline in gazelle mobility over fifteen years as a response to increasing anthropogenic impact. The transportation infrastructure permeating the Eastern Steppe does not pose physical barriers, yet our findings suggest that increasing traffic volume may create semipermeable barriers to gazelle movement. As human activity is increasing, interactions between ungulates and vehicle traffic need to be closely monitored to identify and mitigate semipermeable barrier effects before landscape permeability is severely altered. [ABSTRACT FROM AUTHOR]

Our knowledge of migration ecology has progressed quickly in concert with technological advances that collect fine‐scale movement data through time. We now know that migration plays a critical role in the annual nutritional cycle of large herbivores and that sustaining functional migratory routes is key to long‐term conservation. Yet, we lack basic information on whether one migratory route may function better than another, or more specifically, if choosing one route over another has fitness consequences – knowledge that could help inform conservation and restoration efforts.Here, we examined how a suite of migratory parameters influenced the survival of mule deer Odocoileus hemionus that shared a common winter range in New Mexico, USA, but migrated to various summer ranges in Colorado, USA. We used a Cox proportional hazard model and longitudinal global positioning system data collected over a 7‐year period to investigate whether the mortality risk of 66 deer was affected by choice of migratory route, summer range, migration distance, speed or the number of administrative boundaries each route crossed.We found mule deer survival was not influenced by migratory distance, speed or number of administrative boundaries, but was strongly affected by the choice of migratory route and summer range. The magnitude of these effects was surprisingly large, doubling or tripling mortality risk. Cumulative survival rates showed that regardless of summer range, individuals migrating along high‐use exterior routes had cumulative survival rates approximately 30% lower than individuals migrating along high‐use interior routes. To our knowledge, this is the first direct evidence that a mammal's choice of migration route can influence its probability of survival.Synthesis and applications. Our finding that large herbivores may experience up to three times higher mortality risk by using a different migratory route reveals a novel link between migration and demography. Importantly, our results also suggest that spatially explicit model parameters and predictions could help in the conservation and restoration of migratory populations by identifying specific migratory routes or seasonal ranges that reduce survival. Our finding that large herbivores may experience up to three times higher mortality risk by using a different migratory route reveals a novel link between migration and demography. Importantly, our results also suggest that spatially explicit model parameters and predictions could help in the conservation and restoration of migratory populations by identifying specific migratory routes or seasonal ranges that reduce survival. [ABSTRACT FROM AUTHOR]

The most common framework under which ungulate migration is studied predicts that it is driven by spatio–temporal variation in plant phenology, yet other hypotheses may explain differences within and between species. To disentangle more complex patterns than those based on single species/ single populations, we quantified migration variability using two sympatric ungulate species differing in their foraging strategy, mating system and physiological constraints due to body size. We related observed variation to a set of hypotheses. We used GPS‐collar data from 537 individuals in 10 roe Capreolus capreolus and 12 red deer Cervus elaphus populations spanning environmental gradients across Europe to assess variation in migration propensity, distance and timing. Using time‐to‐event models, we explored how the probability of migration varied in relation to sex, landscape (e.g. topography, forest cover) and temporally‐varying environmental factors (e.g. plant green‐up, snow cover). Migration propensity varied across study areas. Red deer were, on average, three times more migratory than roe deer (56% versus 18%). This relationship was mainly driven by red deer males which were twice as migratory as females (82% versus 38%). The probability of roe deer migration was similar between sexes. Roe deer (both sexes) migrated earliest in spring. While territorial male roe deer migrated last in autumn, male and female red deer migrated around the same time in autumn, likely due to their polygynous mating system. Plant productivity determined the onset of spring migration in both species, but if plant productivity on winter ranges was sufficiently high, roe deer were less likely to leave. In autumn, migration coincided with reduced plant productivity for both species. This relationship was stronger for red deer. Our results confirm that ungulate migration is influenced by plant phenology, but in a novel way, that these effects appear to be modulated by species‐specific traits, especially mating strategies. [ABSTRACT FROM AUTHOR]

Long‐distance migration by terrestrial mammals is a phenomenon critical to the persistence of populations, but such migrations are declining globally because of over‐harvest, habitat loss, and movement barriers. Increasingly, there is a need to improve existing routes, mitigate route segments affected by anthropogenic disturbance, and in some instances, determine whether alternative routes are available. Using a hypothesis‐driven approach, we identified landscape features associated with the primary functional attributes, stopovers and movement corridors, of spring migratory routes for mule deer in two study areas using resource selection functions. Patterns of selection for landscape attributes of movement corridors and stopovers mostly were similar; however, landscape features associated with movement corridors aligned better with areas that facilitated movement, whereas selection of stopovers was consistent with sites offering early access to spring forage. For movement corridors, deer selected for dry sites, low elevation, and low anthropogenic disturbance. For stopovers, deer selected for dry sites, with consistently early green‐up across years, south‐southwesterly aspects, low elevation, and low anthropogenic disturbance. Stopovers and movement corridors of a migratory route presumably promote different functions, but for a terrestrial migrant, patterns of habitat selection indicate that the same general habitat attributes may facilitate both movement and foraging in spring. Our findings emphasize the roles of topographical wetness, vegetation phenology, and anthropogenic disturbance in shaping use of the landscape during migration for this large herbivore. Avoiding human disturbance and tracking ephemeral forage resources appear to be a consistent pattern during migration, which reinforces the notion that movement during migration has a nutritional underpinning and disturbance potentially alters the net benefits of migration. [ABSTRACT FROM AUTHOR]

Long-distance migrations by ungulate species are a globally imperiled natural phenomenon and conservation of them requires monitoring population vital rates. Satellite telemetry tracking is widely used for understanding the spatial distribution and movement of animals, especially migratory animals in remote environments. Recently, analytical methods have been developed to infer parturition events from movement data in multiple species that calve in isolation, but to date such methods have not been tested on animals that both migrate and spatially aggregate during calving. We applied two movement-based methods developed to infer parturition in nonmigratory woodland caribou (Rangifer tarandus caribou (Gmelin, 1788)) to 241 reproductive seasons spanning 6 years of GPS data from migratory barren-ground caribou (Rangifer tarandus granti J.A. Allen, 1902). We compared results from both methods to data from aerial surveys of collared females during the calving period. We found that each movement-based method had ∼80% overall accuracy to identify calving events, with interannual variation ranging from 61% to 100%. When we considered instances when the two analytical methods agreed on parturition outcome, the accuracy increased to 89% with an annual range of 73%–100%. Using these methods, we identified marked interannual differences in peak calving dates and higher parturition rates than previously reported for this caribou herd. The successful application of these analyses to a migratory, gregarious ungulate suggests a broader applicability of the methodology. [ABSTRACT FROM AUTHOR]

ABSTRACT: Ungulate species around the world are habituating to humans and human infrastructure, which can cause the loss of migratory behavior, local overpopulation, ecosystem damage, and human‐wildlife interactions. Wildlife managers sometimes attempt to reduce habituation by subjecting ungulates to aversive conditioning, comprised of negative stimuli in association with specific locations or behaviors, but high variability in the responsiveness of animals has limited the utility of this technique. We studied this limitation using 20 wild elk (Cervus canadensis) inhabiting a mountain town by identifying and comparing the responses of individuals categorized along a personality gradient from shy to bold, subjecting animals to aversive conditioning that either isolated animals or let them remain in a group, and then comparing their wariness via flight response distances before, during, and after conditioning. Bolder elk had significantly greater increases in wariness during conditioning and greater decreases in wariness once the conditioning period was complete. Isolation versus group‐based treatment did not affect responsiveness during the conditioning period, but isolated animals retained more wariness after conditioning ended. These results suggest that wildlife managers could increase the efficacy of aversive conditioning by identifying and targeting specific personality types and individuals to modify behavior and mitigate the broader ecological effects of habituated wildlife. © 2018 The Wildlife Society. [ABSTRACT FROM AUTHOR]

In protected areas, wildlife may lose their fear of humans, and prey species may use human-disturbed areas to escape natural predators. Lateral bedding posture bias may reflect difference in monitoring and these changing patterns of risk stimuli. I studied wild elk in Banff and Jasper National Parks, Canada, where habituated animals enter into conflicts with humans, abandon migration, and negatively affect entire ecosystems. I recorded lateral bedding postures and lateral differences in detection distances when elk were approached. Elk had leftward posture biases when facing away from the herd toward the presumptive direction of potential predation, but had rightward biases when facing towards conspecifics. I found migratory elk had stronger lateral biases than elk residing year-round near humans. These results show lateral posture biases are context dependent on risk, and as these risks change, lateral biases change as well. These results provide important insights for the management of prey species subject to changing patterns of predation and human disturbance, and contribute to our growing understanding of the ecological implications of laterality in wild species. [ABSTRACT FROM PUBLISHER]

Partially migratory populations comprise both resident and migratory individuals. These tactics may coexist if their demographic contribution to future generations (i.e. fitness) are equal or vary temporally with environmental conditions, or if individuals switch between being migrant and resident. Alternatively, the choice of movement tactic can be based on individual attributes such as age, competitive ability or personality. In the latter cases, the two tactics are not expected to have similar average fitness. In this study, we examined the effect of movement tactic on reproductive performance and survival of 82 GPS-marked female moose and their offspring in a partial migratory population in central Norway. The results indicated higher growth in the migrating part of the population because migrating females produced more twins than resident females. We found no differences in pregnancy rates or survival of adults or their offspring, indicating a net fitness benefit of being migrant. We found the average shoulder height of residents to be slightly lower than of migrants, but doubt that this affected their migration ability. A more likely explanation is that migratory females are both more fecund and grow bigger because of better conditions in their summer ranges. This may be a temporal phenomenon if the fitness differences between migratory and resident moose vary according to environmental fluctuations. [ABSTRACT FROM AUTHOR]

Zooarchaeological and paleoecological investigations have traditionally been unable to reconstruct the ethology of herd animals, which likely had a significant influence on the mobility and subsistence strategies of prehistoric humans. In this paper, we reconstruct the migratory behavior of red deer (Cervus elaphus) and caprids at the Pleistocene-Holocene transition in the northeastern Adriatic region using stable oxygen isotope analysis of tooth enamel. The data show a significant change in δ18O values from the Pleistocene into the Holocene, as well as isotopic variation between taxa, the case study sites, and through time. We then discuss the implications of seasonal faunal availability as determining factors in human mobility patterns. [ABSTRACT FROM AUTHOR]

Little research has evaluated how the migration and distribution of native prey influence patterns of livestock depredation by large carnivores. Previous research suggests that the presence of native prey can increase depredation rates by attracting predators (prey tracking hypothesis). Alternatively, the absence of native prey may facilitate predation on livestock (prey scarcity hypothesis). In this study, we evaluated support for these competing hypotheses through analysis of 4 years of cattle ( Bos taurus L., 1758) depredation data ( n = 39 kills), 2 years of summer and fall wolf ( Canis lupus L., 1758) predation and tracking data ( n = 4 wolves), and 3 years of elk ( Cervus elaphus L., 1758) movement data ( n = 70 elk). We used logistic regression to compare the relative influence of landscape features and elk distribution on the risk of livestock depredation in areas with migratory and resident elk. Cattle depredations occurred in habitats with increased encounter rates between wolves and livestock. In resident elk areas, depredation sites were associated with elk distribution and open roads. In migratory elk areas, depredation sites were associated with wolf dens, streams, and open habitat. Patterns of carnivore-livestock conflicts are complex, and using ungulate distribution data can predict and minimize such instances. [ABSTRACT FROM AUTHOR]

Pronghorn (Antilocapra americana) exhibit complex spatial and temporal variation in seasonal movements and range use across their distribution. However, knowledge of seasonal movements, routes, and distribution of pronghorn within the sagebrush-steppe of the northern Great Basin is lacking. From October 2011 to October 2013, I monitored movements of adult female pronghorn across an area of over 1.5 million hectares along the northwestern Nevada and southeastern Oregon border using GPS/VHF-equipped collars. I used 68,834 GPS locations from 32 female pronghorn to determine migration timing, seasonal distributions, individual fidelity to winter and summer ranges, and population-level routes used during the migration period. Collared pronghorn were conditionally migratory, with 65% migrating an average of 30.0 km the first year and 100% migrating an average of 39.1 km the second; one individual migrated over 160 km between summer and winter ranges. Seasonal ranges averaged 143.3 km² during the summer, and from 252.9 to 459.9 km² during the winter (2010/2011 and 2011/2012, respectively). Individual pronghorn demonstrated wide variation in directional movement between summer and winter ranges, and there was high overlap of common areas across seasons and time periods. Pronghorn showed stronger fidelity to summer ranges than to winter ranges, and occupied higher elevations during the summer months, descending to lower elevations during the winter. Deeper snow and colder temperatures in 2012/2013 compared to 2011/2012 corresponded to longer average migration distances, fewer exploratory movements, larger winter ranges, lower elevational use, and a shift in winter range location. Habitat conversion, degradation, and fragmentation have accumulated across the sagebrush-steppe biome and are negatively affecting the long-term persistence of dependent wildlife. Applying knowledge of important seasonal use areas and routes used during migration in future conservation planning can mitigate impacts to pronghorn habitat and provide for long-term conservation. [ABSTRACT FROM AUTHOR]

Mesocarnivores increase in number and geographic range in human-disturbed ecosystems with cascading negative impact on biodiversity. To mitigate such impacts, it is essential to identify the proximate causes of such mesocarnivore releases. Here, we assess to what extent increased partial migration in semi-domesticated tundra reindeer induce a response in boreal and arctic mesocarnivores., We used a large-scale and multiyear quasi-experimental study design with camera traps deployed on coastal tundra peninsulas in northern Norway to estimate area occupancy of the whole carnivore community. These peninsulas represent summer pastures for separate semi-domestic reindeer herds that, owing to different degrees of partial migration, now display spatially and temporally variable densities of year-round resident reindeer. We estimated resident reindeer density by means of aerial surveys., Area occupancy of all the recorded carnivore species increased strongly when resident reindeer densities exceeded 1·5 deer km−2., Most of the increasing carnivore species were typical boreal forest species, implying range expansions into tundra when provided with stable food resources (prey and carrion) in terms of resident reindeer., Synthesis and applications. We found that boreal mesocarnivores, known to negatively impact the productivity of reindeer and arctic wildlife of conservation concern, steeply increased in tundra areas with many year-round resident reindeer due to increased partial migration. To avoid such negative impacts, actions should be taken to minimize residency in tundra reindeer. [ABSTRACT FROM AUTHOR]

Snow is one of the most limiting environmental factors for large wildlife of temperate and arctic zones during winter. Snow depth may limit space use, increase energy expenditure related to movement, limit resource availability, and ultimately affect individual survival. Most of the studies on the effect of snow on animal space use have used cumulative snow depth. The amount of recently fallen snow, however, could be more relevant for wildlife, especially in alpine and northern environments, where wind shifts and hardens the snow cover constantly. From 2011 to 2013, we studied space use of mountain goats ( Oreamnos americanus (Blainville, 1816)) within Jasper National Park in Alberta, Canada. During winter, daily and weekly movements decreased with the amount of recently fallen snow, but not with cumulative snow depth. These results indicate that recently fallen snow should be included in wildlife space-use studies during winter. Limited movement and range size of mountain goats also highlight the energy-saving tactic used in winter by this species. [ABSTRACT FROM AUTHOR]

Conservation of migration requires information on behavior and environmental determinants. The spatial distribution of forage resources, which migration exploits, often are altered and may have subtle, unintended consequences. Supplemental feeding is a common management practice, particularly for ungulates in North America and Europe, and carryover effects on behavior of this anthropogenic manipulation of forage are expected in theory, but have received limited empirical evaluation, particularly regarding effects on migration. We used global positioning system (GPS) data to evaluate the influence of winter feeding on migration behavior of 219 adult female elk (Cervus elaphus) from 18 fed ranges and 4 unfed ranges in western Wyoming. Principal component analysis revealed that the migratory behavior of fed and unfed elk differed in distance migrated, and the timing of arrival to, duration on, and departure from summer range. Fed elk migrated 19.2 km less, spent 11 more days on stopover sites, arrived to summer range 5 days later, resided on summer range 26 fewer days, and departed in the autumn 10 days earlier than unfed elk. Time-to-event models indicated that differences in migratory behavior between fed and unfed elk were caused by altered sensitivity to the environmental drivers of migration. In spring, unfed elk migrated following plant green-up closely, whereas fed elk departed the feedground but lingered on transitional range, thereby delaying their arrival to summer range. In autumn, fed elk were more responsive to low temperatures and precipitation events, causing earlier departure from summer range than unfed elk. Overall, supplemental feeding disconnected migration by fed elk from spring green-up and decreased time spent on summer range, thereby reducing access to quality forage. Our findings suggest that ungulate migration can be substantially altered by changes to the spatial distribution of resources, including those of anthropogenic origin, and that management practices applied in one season may have unintended behavioral consequences in subsequent seasons. [ABSTRACT FROM AUTHOR]

The costs and benefits of alternative migratory strategies are often framed in the context of top-down and bottom-up effects on individual fitness. This occurs because migration is considered a costly behavioral strategy that presumably confers explicit benefits to migrants in the form of either decreased prédation risk (prédation risk avoidance hypothesis) or increased nutrition (forage maturation hypothesis). To test these hypotheses, we studied a partially migratory moose (Alces alces) population and contrasted explicit measures of prédation risk (i.e., offspring survival) and nutrition (i.e., accumulation of endogenous energy reserves) between resident and migratory subpopulations. We relied on data collected from migratory and nonmigratory radio-marked moose (n = 67) that inhabited a novel study system located in coastal Alaska between 2004 and 2010. In this area, 30% of the population resides year-round on a coastal foreland area, while 48% migrate to either a small island archipelago or a subalpine ridge system (the remainder exhibited one of six different low-occurrence strategies). Overall, we determined that accumulation of body fat during the growing season did not differ between migratory or resident modalities. However, calf survival was 2.6-2.9 times higher for individuals that migrated (survival, islands = 0.49 ± 0 . 1 6 [mean ± SE], n = 35; ridge = 0.52 ± 0.16, n = 33) than those that did not (survival, resident = 0.19 ± 0.08, n = 57). Our results support the prédation risk avoidance hypotheses, and suggest that migration is a behavioral strategy that principally operates to reduce the risk of calf prédation and does not confer explicit nutritional benefits. We did not directly detect trade-offs between prédation risk and nutrition for migratory individuals. Yet we identify an indirect life history mechanism that may mildly dampen the apparent fitness benefits of migration. The proximate factors accounting for differences in migration-specific neonate survival are likely linked to accessibility of réfugiai habitats for moose at local and landscape scales, landscape factors that affect hunting efficacy of large carnivores, and interactions with rural human communities. Conservation of ungulate populations can be aided by integrating knowledge about migratory behavior, life history strategies, and factors that alter ungulate vulnerability, particularly those induced by human activity. [ABSTRACT FROM AUTHOR]

The article offers information on the effect of elk migration patterns and human activity on the use of wolf habitat at the Greater Yellowstone ecosystem in the U.S. As mentioned, the study compared the seasonal habitat use of wolves in an area dominated by migratory elks and resident elks. It also mentions of the importance of such studies for the management and conservation of wildlife populations.