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Snow urine samples collected in northern New Hampshire, USA were used to measure urea nitrogen (UN) and creatinine (C) content to develop ratios for tracking the nutritional restriction of individual moose (Alces alces) through winter (2014-2017), inclusive of the adult winter tick (Dermacentor albipictus) engorgement period. Samples (n = 215) were collected from 55 moose (38 calves, 17 cows) on a twice monthly schedule from late January through snowmelt or calf mortality (March - early April). Early winter UN:C ratios from cows, surviving calves, and calves that ultimately died from infestation of winter ticks were similar and reflected a normal winter diet low in protein. A heightened UN:C ratio (> 3.5 mg/dL) was measured in March which aligned with peak feeding by adult winter ticks, and presumably reflected accelerated protein deficit associated with blood loss. This increase was not observed population-wide despite shared habitat, occurring only in calves with mortal weight loss and anemia associated with heavy winter tick infestation. Measurement of UN:C ratios from snow urine samples proved an effective method to measure the temporal impact of winter tick infestation, and March samples can support other metrics used to estimate calf mortality. [ABSTRACT FROM AUTHOR]

Abundance indices suggested that the moose Alces alces population in northern New Hampshire was stable despite favourable habitat and conservative harvest. Causes and rates of mortality were unknown because moose reproduction and survival was unstudied in the region. Our study was designed to investigate the dynamics of the regional population in 2002-2005.Atotal of 92 moose (33 cows and 59 calves) were captured and fitted with radio-collars (VHF=83, GPS= 9). Parturition ranged from 8 May to 13 July (median = 19 May) with 78% of births occurring during 13-27 May. Calving rate of yearlings and adults (>2 years old) averaged 30 and 85%, respectively; twinning rate was 11%. Analysis of reproductive data from harvested cows (1988-2004) indicated that the average weight of adult cows increased but their corpora lutea count declined from ; 1.4 to 1.2/cow. Both ovulation rate and average weight of yearling cows declined about 25 and 4%, respectively. There were 39 mortalities (49% calves) with winterkill/parasite (41%), vehicle collision (26%) and hunting (18%) as the leading causes. Major sources of mortality of radio-marked cows were human-related; survival was 0.87. Annual calf survival was 0.45. Unmarked calf (0-2 months of age) survival was 0.71 with 76% of mortality in the first month of life. Radio-marked calves (∼7-12 months of age) had a survival rate of 0.67; 74% of the mortality was winterkill/parasite related. Calf mortality was concentrated (88%) in late winter-early spring. The unseasonably warm and snowless fall in 2001 probably favoured high tick transmission and increased tick loads on moose that resulted in high calf mortality (0.51) and measurable cow mortality (10%) in mild winter-spring 2002. Documentation of substantial tick-related mortality of radio-marked moose calves was unique to this study. The stability of the moose population probably reflects the variation in annual recruitment and lower fecundity of yearling cows associated with heavy infestations and epizootics of winter tick. Given that fertility, calving rate and body condition of adult cows, and summer calf survival are annually high, the population should recover from tick epizootics that periodically inhibit population growth. [ABSTRACT FROM AUTHOR]

Habitat use by parturient moose (Alces alces) may have important implications for calf survival and subsequently influence population dynamics. Because neonatal habitat may be limiting or specialized and little descriptive information exists in the northeastern United States, this study was conducted to measure the physical and vegetative characteristics associated with neonatal habitat of 30 maternal moose. There was no difference (P > 0.10 for each parameter) in 22 of 23 physical and vegetative parameters measured at neonatal (n = 30) and random sites (n = 30). However, neonatal sites were about 2X farther (P = 0.032) than random sites from cut/regeneration habitat where no neonatal site occurred. Most neonatal sites (> 63%) were located in pole or saw timber stands comprised of mixed or coniferous habitat (> 75%); conifers were the dominant canopy species at 67% of neonatal sites. Characteristics related to forage availability suggest that forage resources were probably not influential in location of neonatal habitat. Mature, mixed, and coniferous habitats may provide microhabitat that helps conceal neonates from potential predators such as black bears (Ursus americana), particularly in the absence of islands and open water that are believed to mitigate predation. [ABSTRACT FROM AUTHOR]