Variation in body condition of moose calves in regions with contrasted winter conditions and tick loads

Abstract

For many mammals living at higher latitudes, food scarcity and snow-hindered movements associated with their first winter are synonymous of trying months. In addition, most wild animals have to cope with parasites. Many studies have been conducted on captive animals to assess consequences parasitism on health over winter but comparable studies on wild populations are scarce for large mammals. Here, we performed winter tick (Dermacentor albipictus (Packard, 1869)) counts and collected body condition data (mass and hematological parameters) on 15 moose (Alces alces (Linnaeus, 1758)) calves from two distinct climatic regions in northern and southern New Brunswick (Canada) in January. The same calves were recaptured 3 months later to observe variation in body condition parameters. Higher tick loads and more drastic changes of hematological parameters such as hematocrit and creatinine in southern individuals suggested that this population might be suffering more from the consequences of winter tick infestation than the northernmost population. However, other parameters that were not measured in our study, such as quantity and quality of food, could influence moose calves body condition at the southeastern limit of their range.