Supervised by:

Steeve Côté (Regular member)

Co-supervised by:

Christian Dussault (External collaborator)

Research project description

Interactions between winter tick (Dermacentor albipictus) and moose (Alces alces) in Eastern Canada

IntroductionGlobal warming has several consequences for ecosystems, such as shifting the range of species and bringing forward the life cycle stages of some organisms. These changes can affect the interactions between species, and between host and parasite in particular. Variations in precipitation and atmospheric conditions could be favourable to the winter tick and thus be responsible for mass mortalities in certain moose populations. This project aims to develop tools to anticipate winter tick epizootics and formulate management recommendations to reduce their effects on moose. ObjectivesThis project aim to : Characterize the micro-habitats suitable for the survival of the winter tick to create a map of tick occurrence and intensity; Determine whether winter tick larvae are able to survive the winter in the absence of a host and what proportion of a group of ticks actually seek a host on vegetation; Determine if ticks in Quebec and New Brunswick can adapt to local temperature and humidity conditions; Study moose activity budgets according to their degree of winter tick infestation during the critical infestation period; Compare habitat selection of acaricide-treated and untreated moose during the critical winter tick infestation period. Study sitesOur study will focus on moose populations along a gradient of latitude and density from southern New Brunswick to northern Saint-Lawrence River. On the northern shore of the Saint-Lawrence River, we will study moose populations from the Seigneurie de Beaupré near Quebec City and in the southwest of Quebec close to the wildlife reserve of the Vérendrye. On the southern shore, we will study moose populations in the wildlife reserve of Rimouski, the ‘zone d’exploitation contrôlée’ of the Bas-Saint-Laurent (Lower Saint-Lawrence) and the Forillon National Park. Our final study site is in southern New Brunswick. Material and methodsCalves have been and will be captured in 2020, 2022 and 2023 at the five study sites. The movements and activity of each calf are monitored using a GPS collar coupled with an accelerometer and the tick burden is manipulated by applying acaricide to half of the calves captured. These data will be used to calculate moose activity budgets based on their tick load and to understand their habitat selection via RSFs. Ticks will also be flagged at our various sites to determine their abundance and occurrence. These tick and moose GPS data will be combined with environmental data (weather and LIDAR) to determine factors influencing co-occurrence between winter ticks and moose. Finally, we will breed ticks in captivity to test the resistance of larvae to different temperature and humidity conditions, depending on where they come from, and their survival over winter in the wild. ReferencesSamuel, W. M. 2007. Factors affecting epizootics of winter ticks and mortality of moose. Alces 43:39–48. Samuel, B. 2004. White as a Ghost: Winter Ticks & Moose. Federation of Alberta Naturalists, Edmonton, Canada. Holmes, C. J., C. J. Dobrotka, D. W. Farrow, A. J. Rosendale, J. B. Benoit, P. J. Pekins, et J. A. Yoder. 2018. Low and high thermal tolerance characteristics for unfed larvae of the winter tick Dermacentor albipictus (Acari: Ixodidae) with special reference to moose. Ticks and Tick-borne Diseases 9:25–30. Addison, E. M., R. F. McLaughlin, P. A. Addison, et J. D. Smith. 2016. Recruitment of winter ticks (Dermacentor albipictus) in contrasting forest habitats, Ontario, Canada. Alces 52:29–40.

Research Site Coordinates