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David W. Wattles

Publications and source records attributed to David W. Wattles.

7 recordsLinked to original sources

Response of moose to a high‐density road network

Road networks and the disturbance associated with vehicle traffic alter animal behavior, movements, and habitat selection. The response of moose ( Alces americanus ) to roads has been documented in relatively rural areas, but less is known about moose response to roads in more highly roaded landscapes. We examined road‐crossing frequencies and habitat use of global positioning system (GPS)‐collared moose in Massachusetts, USA, where moose home ranges have road densities approximately twice that of previous studies. We compared seasonal road‐crossing frequencies of moose with a null movement model. We estimated moose travel speeds during road‐crossing events and compared them with speeds during other home range movements. To estimate the extent of the road effect zone and determine how roads influenced moose habitat use, we fit a third‐order resource selection function. With the exception of the lowest use road class (<10 vehicles/day), we found moose crossed roads less than expected based on the null movement model and frequency decreased with increasing road size and traffic. Moose crossed roads faster than they traveled during other times. This effect increased with increasing road use intensity. Overall, roads were a major factor determining what portions of Massachusetts moose used and how they moved among habitat patches. Our results suggest that moose in Massachusetts can adapt to a high‐density road network, but the road effect is still strongly negative and, in some cases, is more pronounced than in study areas with lower road densities. Future road construction and the expansion of road networks may have a large effect on moose and other wildlife.

Journal of Wildlife Management

Range expansion in unfavorable environments through behavioral responses to microclimatic conditions: Moose (Alces americanus) as the model

Wildlife populations occurring at the edge of their range boundaries are thought to be the most sensitive to climate change due to temperatures being at or near the limit of a species’ thermal envelope. Moose ( Alces americanus ) are a cold adapted species that are showing population declines in some portions of the southern edge of their range. However, other moose populations are actively expanding southward into thermally stressful areas. The direct effects of temperature on moose have not yet been studied in these southwardly expanding populations and may offer insights into how moose are successfully establishing in areas at the edge of their thermal envelope. We used ambient temperature and GPScollar data from moose to quantify the direct effect of temperature on moose habitat use in Massachusetts, USA, which is one of these southwardly expanding populations. The mean daily temperature in our study area exceeded the reported physiological tolerances of moose in over 90% of daytime and 75% of nighttime locations in summer and in over 80% of daytime and 67% of nighttime locations in winter. Across seasons and times of day, moose preferred regenerating forest, but as ambient air temperatures increased, selection for regenerating forest declined and selection for forested wetlands and coniferous forestincreased. This response indicates moose are altering their behavior to utilize thermal shelters when temperatures are high. We observed higher temperatures and stronger behavioral responses than other studies at the southern edge of moose range. We found habitat for moose in Massachusetts is climatically marginal and loss of habitat, increase in parasites, and further climatic warming may cause population declines in the future.

Mammalian Biology

Space use and movements of moose in Massachusetts: implications for conservation of large mammals in a fragmented environment

Moose ( Alces alces ) have recently re-occupied a portion of their range in the temperate deciduous forest of the northeastern United States after a >200 year absence. In southern New England, moose encounter different forest types, more human development, and higher temperatures than in other parts of their geographic range in North America. We analyzed seasonal minimum convex polygon home ranges, utilization distributions, movement rates, and home range composition of GPS-collared moose in Massachusetts. Seasonal home range sizes were not different for males and females and were within the range reported for low latitudes elsewhere in North America. Seasonal movement patterns reflected the seasonal changes in metabolic rate and the influence of the species’ reproductive cycle and weather. Home ranges consisted almost entirely of forested habitat, included large amounts of conservation land, and had lower road densities as compared to the landscape as a whole, indicating that human development may be a limiting factor for moose in the region. The size and configuration of home ranges, seasonal movement patterns, and use relative to human development have implications for conservation of moose and other wide-ranging species in more highly developed portions of their ranges.

Massachusetts

Moose habitat in Massachusetts: Assessing use at the southern edge of the range

Moose (Alces alces) have recently re-occupied a portion of their range in the temperate deciduous forest of the northeastern United States after a more than 200 year absence. In southern New England, moose are exposed to a variety of forest types, increasing development, and higher ambient temperatures as compared to other parts of their geographic range. Additionally, large-scale disturbances that shape forest structure and expansive naturally occurring shrub-willow communities used commonly elsewhere are lacking. We used utilization distributions to determine third order habitat selection (selection within the home range) of GPS-collared moose. In central Massachusetts, forests regenerating from logging were the most heavily used cover type in all seasons (48 - 63% of core area use). Habitat use of moose in western Massachusetts varied more seasonally, with regenerating forests used most heavily in summer and fall (57 and 46%, respectively), conifer and mixed forests in winter (47 - 65%), and deciduous forests in spring (41%). This difference in habitat selection reflected the transition from northern forest types to more southern forest types across the state. The intensive use of patches of regenerating forest emphasizes the importance of sustainable forest harvesting to moose. This study provides the first assessment of habitat requirements in this southern portion of moose range and provides insights into re-establishment of moose in unoccupied portions of its historic range in New York and Pennsylvania.

Massachusetts, New Hampshire, Vermont

How landscape dynamics link individual- to population-level movement patterns: A multispecies comparison of ungulate relocation data

Aim To demonstrate how the interrelations of individual movements form large-scale population-level movement patterns and how these patterns are associated with the underlying landscape dynamics by comparing ungulate movements across species. Locations Arctic tundra in Alaska and Canada, temperate forests in Massachusetts, Patagonian Steppes in Argentina, Eastern Steppes in Mongolia. Methods We used relocation data from four ungulate species (barren-ground caribou, Mongolian gazelle, guanaco and moose) to examine individual movements and the interrelation of movements among individuals. We applied and developed a suite of spatial metrics that measure variation in movement among individuals as population dispersion, movement coordination and realized mobility. Taken together, these metrics allowed us to quantify and distinguish among different large-scale population-level movement patterns such as migration, range residency and nomadism. We then related the population-level movement patterns to the underlying landscape vegetation dynamics via long-term remote sensing measurements of the temporal variability, spatial variability and unpredictability of vegetation productivity. Results Moose, which remained in sedentary home ranges, and guanacos, which were partially migratory, exhibited relatively short annual movements associated with landscapes having very little broad-scale variability in vegetation. Caribou and gazelle performed extreme long-distance movements that were associated with broad-scale variability in vegetation productivity during the peak of the growing season. Caribou exhibited regular seasonal migration in which individuals were clustered for most of the year and exhibited coordinated movements. In contrast, gazelle were nomadic, as individuals were independently distributed and moved in an uncoordinated manner that relates to the comparatively unpredictable (yet broad-scale) vegetation dynamics of their landscape. Main conclusions We show how broad-scale landscape unpredictability may lead to nomadism, an understudied type of long-distance movement. In contrast to classical migration where landscapes may vary at broad scales but in a predictable manner, long-distance movements of nomadic individuals are uncoordinated and independent from other such individuals. Landscapes with little broad-scale variability in vegetation productivity feature smaller-scale movements and allow for range residency. Nomadism requires distinct integrative conservation strategies that facilitate long-distance movements across the entire landscape and are not limited to certain migration corridors.

Alaska, Massachusetts

Status and management of moose in the northeastern United States

Moose (Alces alces) populations have recolonized much of their historic range in the northeastern United States in the past 30 years, with their southern range edge extending to southern New England and northern New York. This southerly expansion occurred when certain other populations in the United States were in decline along the southern range edge, with climate change often cited as a probable cause. The areas that moose have recently occupied in the northeastern United States are some of the most densely human populated in moose range, which has raised concern about human safety and moose-vehicle collisions (MVC). We conducted a literature search about moose in the northeastern United States, and distributed a questionnaire and conducted phone interviews with regional biologists responsible for moose management to determine the status of moose, management activity, and research deficiencies and needs. Moose numbers appear stable throughout much of the region, with slow population growth in northern New York. Management activity ranges from regulated harvest of moose in Maine, New Hampshire, and Vermont, to no active management in southern New England and New York. The combined annual harvest in Maine, New Hampshire, and Vermont is >3,000. MVCs are a widespread regional concern with >1,000 occurring annually involving several human fatalities. Research should address impacts of parasitism by winter tick (Dermacentor albipictus) and brain-worm (Parelaphostrongylus tenuis) on productivity and mortality of moose, influence of climate change on population dynamics and range, and conflicts in areas with high human population density.

Alces