The effect of thermoregulation and roads on the movements and habitat selection of moose in Massachusetts

Massachusetts, U.S.A. is located along the southern boundary of the geographic range of moose (Alces alces) in North America. This is an atypical environment for moose, because of its extremely high levels of human development and high year-round temperatures, which are possibly at the limits of moose physiological tolerances. I investigated the role of these two factors on moose movements and habitat selection to determine how human development of the landscape and temperature influence moose occupation of this extreme environment. In addition, the response of moose to these factors provides insights into the influence of development and temperature on individual fitness and population persistence. Thermal conditions in Massachusetts were consistently higher than the reported physiological tolerances of moose, and higher than parts of the range where high temperatures have negatively affected moose reproduction and survival. Moose greatly reduced their selection of open foraging habitat and increased selection for thermal shelters as temperatures increased above upper critical limits; this same pattern was apparent when comparing day (warmer) to night (cooler) activities. A strong transition in the use of habitats occurred at dawn and dusk, which corresponded to peaks in hourly movement rates at these times, indicating a transition in state from foraging at night to bedding during the day. The ability of moose to adapt to this extreme thermal environment through thermoregulatory behaviors reveals the limitations of predicting species distributions based solely on theoretical temperature tolerances. Massachusetts has one of the highest rates of moose-vehicle collisions (MVCs) per-capita moose and resulting human fatalities. The majority (86%) of MVCs occurred on roads with high speed limits and traffic volumes, and occurred on these roads at much higher rates than would be predicted based on their availability on the landscape. The dense road network in Massachusetts had a strong negative effect on the movements and habitat selection patterns of moose. Moose avoided crossing roads and greatly reduced their use near roads. Road avoidance increased with increasing disturbance intensity associated with higher traffic volumes and busier times of day. Roadways reduced habitat availability and connectivity, were a major source of additive mortality for moose