As climate change profoundly alters ecosystems in North America, a small parasite is wreaking havoc: the winter tick. This tick, now more prevalent due to milder environmental conditions, is severely affecting the winter survival of young moose in eastern Canada.
Climate change is allowing species such as the winter tick — an external parasite that feeds on the blood of large deer — to spread to new regions. Once rarer in eastern Canada, the tick is now well established there and is causing high mortality, especially among young moose.
The winter tick completes its entire life cycle by infesting a single host. In addition to moose, it can be found on other deer species, such as white-tailed deer and caribou, on which it has little effect.
