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Recent decline in New Hampshire's moose (Alces alces) population is attributed to sustained parasitism by winter ticks (Dermacentor albipictus) causing high calf mortality and reduced productivity. Location of larval winter ticks that infest moose is dictated by where adult female ticks drop from moose in April when moose preferentially forage in early regenerating forest in the northeastern United States. The primary objectives of this study were to: 1) measure and compare larval abundance in 2 types of regenerating forest (clear-cuts and partial harvest cuts), 2) measure and compare larval abundance on 2 transect types (random and high-use) within clear-cuts and partial harvests, and 3) identify the date and environmental characteristics associated with termination of larval questing. Larvae were collected on 50.5% of 589 transects; 57.5% of transects in clear-cuts and 44.3% in partial cuts. The average abundance ranged from 0.11-0.36 ticks/[m.sup.2] with abundance highest (P < 0.05) in partial cuts and on high-use transects in both cut types over a 9-week period; abundance was ~2 * higher during the principal 6-week questing period prior to the first snowfall. Abundance (collection rate) was stable until the onset of < 0[degrees]C and initial snow cover (~15 cm) in late October, after which collection rose temporarily on high-use transects in partial harvests during a brief warm-up. The higher abundance of winter ticks on high-use transects indicates that random sampling underestimates tick abundance and relative risk of infestation of moose. Calculating an annual index of infestation of winter ticks on moose is theoretically possible by integrating 3 factors: the infestation of harvested moose in October, the length of the questing period, and assuming a stable collection rate during the questing period. ALCES VOL. 56: 1-13 (2020) Key Words: Alces alces, Dermacentor albipictus, forest habitat, infestation, moose, questing, tick abundance, winter ticks, The influence of winter ticks (Dermacentor albipictus) on population dynamics of moose (Alces alces) in the northeastern United States (northeast) is well documented (Musante et al. 2010, Bergeron et al. [...]

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. ALCES VOL. 55: 13-21 (2019) Key words: creatinine, epizootic, New Hampshire, moose, nutritional restriction, snow urine, urea nitrogen, winter ticks, New Hampshire has experienced at least 5 winter tick (Dermacentor albipictus) epizootics (> 50% calf mortality) in the last decade, an unprecedented rate of occurrence (Musante et al. 2010, Bergeron [...]

Moose (Alces alces) populations in northern New Hampshire and western Maine experienced 3 successive years of high winter tick infestations (epizootics) in 2014-2016 that resulted in late-winter calf mortality rates >70%. To assess productivity in these populations, we measured fecundity rates of yearling and adult cow moose, and neonatal and summer calf survival. Parturition, fecundity, and survival were measured via direct observation by stalking VHF and GPS radio-collared cows (n = 177) in May-August, 2014-2016. Calving rates for yearlings and adults averaged 0 and 57%, respectively; there was no twinning documented. Summer calf survival to August was high overall (83%), with 85% of the mortality occurring in the first week of life. Calving and twinning rates declined since last measured in New Hampshire in 2002-2005 and were below the North American average; conversely, summer survival of calves was considered normal. Given that optimal habitat has increased in the past 15 years in the study area that is dominated by commercial forestry, lower productivity is presumably related to the additive impacts of successive winter tick epizootics on year-round condition of cows. Key Words: Alces alces, calving, fecundity, Maine, neonate survival, New Hampshire, pregnancy, winter ticks, Many moose (Alces alces) populations along the southern edge of their North American range are declining, including in Minnesota, Manitoba, Nova Scotia, Vermont, New York, and New Hampshire (Murray et [...]

An isolate of the soil fungus Scopulariopsis brevicaulis was identified from the surface of female winter ticks (Dennacentor albipictus) collected from recently dead moose (Alces alces) calves in New Hampshire in the northeastern United States. It was the sole isolate, and it matched with 98% nucITS similarity (molecular systematics Blast match) to S. brevicaulis species from soil and other tick species. Inoculation of tick larvae and eggs with [10.sup.8] spores/mL + 0.05% Tween (aqueous inoculum) resulted in mortality, reduced survival time, and recovery of S. brevicaulis from within tick tissues. Rapid water loss and death from dehydration were the pathogenic consequences of the fungal infection. Three entomopathogenic fungal isolates from laboratory culture (Beauveria bassiana, B. caledonica, and Metarhizium anisopliae) inoculated concurrently at the same dose, were slightly less pathogenic to eggs than larvae of winter ticks. We conclude that S. brevicaulis imposes a limitation on the free-living stages of the winter tick population in specific environmental conditions, but commercial fungal treatments as used in local situations to control ticks, are impractical as a means of controlling winter tick density across moose habitats. Key words: Alces alces, Dermacentor albipictus, moose, pathogenic fungi, Scopulariopsis brevicaulis, survival, water balance, winter ticks, INTRODUCTION Winter ticks (Dermacentor albipictus) periodically cause high calf mortality in moose (Alces alces) populations in the northeastern United States and southern Canada due to numerous interactive stressors, including extreme [...]

ABSTRACT: Winter habitat use by moose (Alces alces) is typically comprised of regenerating forest and softwood cover in the northeastern United States, and globally, high winter densities are of concern [...]

ABSTRACT: Age, field-dressed body weight, and antler spread data collected from 11,566 harvested moose (Alces alces) were analyzed to assess whether temporal change has occurred in the physical characteristics of [...]

Moose (Alces alces) play an important role in the ecological and economic resources of northern New England, a landscape dominated by commercial forests. This study measured the impact of moose browsing on forest regeneration in Wildlife Management Unit E1 in northeastern Vermont where moose density was considered high in the 1990-2000s. We surveyed 37 clearcuts categorized into 4 age classes (3-5, 6-10, 11-15, and 16-20 years old). The stocking rate (stems/plot) of commercial species ranged from 74-76% in the 3-5, 6-10, and 11-15 year age classes, increasing to 86% in the 16-20 year age class. The proportion of plots containing a commercial tree without severe damage was above the accepted threshold stocking level of 40-60% in all age classes. The proportion of plots containing a commercial hardwood stem declined with increasing age class; the opposite occurred with softwood stems indicating a possible shift from hardwood- to softwood-dominated stands from selective browsing pressure. Height of 11-20 year old stems was less than in New Hampshire, indicating that growth was possibly suppressed in Vermont due to higher moose density. Overall, browsing was not considered a major problem based upon stocking rates. Further study is warranted to evaluate whether compensatory growth occurs in response to reduced browsing as forests age and/or moose population density declines. Key words: Alces alces, browsing, clearcut, damage, moose, New England, regeneration, stocking., Moose (Alces alces) populations have experienced a regional increase in northern New England over the last several decades, making them an increasingly valuable wildlife resource. They play an important role [...]

In New Hampshire, winter ticks (Dermacentor albipictus) probably have more influence on the moose (Alces alces) population than other mortality factors, and predicting the frequency of tick epizootics is an important management consideration. Weather, moose density, and habitat use influence abundance and distribution of winter ticks. We evaluated the usefulness of 3 techniques to index winter tick abundance in 3 regions with variable moose density: 1) flagging for tick larvae, 2) line-transect counts of ticks on harvested moose, and 3) roadside surveys of tick-induced hair-loss on moose. Although counts of tick larvae from fall flagging were not significantly different between years or regions, absolute tick abundance was measurably different (>50%) relative to moose density and years. Tick abundance on harvested moose reflected annual and regional differences; in general, abundance was correlated positively with moose density and annual trends within regions were similar. Tick abundance was highest for calves and lowest for cows. Hair-loss surveys indicated that hair loss was generally related to moose density, and similar annual differences were reflected in all regions. We suggest measuring tick abundance on harvested moose and conducting annual roadside hair-loss surveys to create indices and threshold values useful in predicting an epizootic of winter ticks. Key words: Alces alces, Dermacentor albipictus, hair loss, index, moose, winter tick, The winter tick (Dermacentor albipictus) is a unique blood-feeding ectoparasite that periodically causes severe mortality in moose (Alces alces) populations (Cameron and Fulton 1926-27, Samuel and Barker 1979). It is [...]

ABSTRACT: Biological data collected from harvested moose (Alces alces) were analyzed to assess whether temporal change has occurred in the physical and reproductive condition of moose from 1988-2009 in New [...]

ABSTRACT: The impact of moose (Alces alces) browsing on the regeneration of commercial hardwood and softwood tree species was evaluated in 3 regions with different moose population densities (0.26-0.83 moose/[km.sup.2]) [...]

ABSTRACT: Moose (Alces alces) are susceptible to late winter mortality from infestation of winter ticks (Dermacentor albipictus) throughout much of North America. Calves, perhaps more so than other ages of [...]

ABSTRACT: 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 [...]

ABSTRACT: The New Hampshire Fish and Game Department and the University of New Hampshire initiated research in northern New Hampshire to better understand population dynamics and seasonal habitat use of [...]

ABSTRACT: We examined behavioral response of moose to wildlife viewers and traffic stimuli at a moose viewing blind located on a roadside salt lick in northern New Hampshire during summer, [...]

ABSTRACT: In northern New Hampshire, we examined the use patterns of moose visiting a roadside salt lick before (1996) and after (1997-1999) a blind was built specifically to view moose [...]

Many wildlife populations are experiencing a variety of environmental pressures due to the direct and indirect consequences of a changing climate. In the northeast, USA, moose Alces alcesare declining in large part because of the increasing parasitism by winter tick Dermacentor albipictus, facilitated by high host density and optimal environmental conditions. To test this hypothesis, and better understand the influence of this interaction on the stability of the regional population, we constructed a population viability model using data collected through comprehensive survival and productivity studies in 2002–2005 and 2014–2018 in northern New Hampshire. Years of heavy tick infestation (epizootics) saw a marked reduction in calf survival (< 50%), adult calving (< 60%), twinning rate (< 5%) and complete loss of yearling productivity. We conducted population viability analysis using VORTEX ver. 10.2 to model this moose population for 40 years using mean demographics from both time periods, including environmental variation measured in the field during winter tick epizootic (2002, 2014, 2015, 2016) and non-epizootic (2003, 2004, 2005, 2017) years. This exercise highlights the influence of winter tick infestation on the trajectory of the population with the potential for rapid population growth or decline depending on the frequency of epizootics. We suggest a shift in moose management strategy focused on lowering moose density, assuming continued influence of climate change on the host–parasite relationship.