A study conducted by researchers at the University of Alaska Fairbanks’ Institute of Arctic Biology has revealed the presence of a “traveling population wave” among Canada lynx populations in Interior Alaska, which significantly impacts their reproduction, movement, and survival. This discovery has the potential to assist wildlife managers in making more informed decisions regarding the management of these key predators in the boreal forest. The traveling population wave is a common phenomenon in biology, where animal populations fluctuate in number across a region, resembling a ripple effect.
The Canada lynx populations in Alaska are known to follow a 10- to 12-year cycle, mirroring the boom-and-bust cycle of their primary prey, the snowshoe hare. During periods of hare population growth, lynx numbers also rise, but when food becomes scarce, the hare population crashes, leading to a decline in lynx numbers, typically one to two years later. The study, spanning from 2018 to 2022, monitored 143 lynx in five national wildlife refuges in Interior Alaska, fitted with GPS collars to track their movements and behavior during the population collapse.
The researchers identified three distinct stages in which lynx responded to the collapse of the snowshoe hare population. First, there was a sharp decline in reproduction, with litter sizes decreasing drastically. This was followed by increased dispersal, as lynx ventured out of their territories in search of better conditions, traveling significant distances across various landscapes. Finally, survival rates dropped, particularly for lynx moving against the population wave direction, such as eastward, experiencing higher mortality rates compared to those moving westward or staying in their original territories.
The findings from the study confirmed observations made by trappers and experts in the field, providing concrete evidence of the traveling population wave phenomenon. Understanding this pattern can help wildlife managers predict and manage lynx populations more effectively on a local scale. Maintaining refuge populations was highlighted as crucial, as dispersing lynx during population declines face lower survival rates, emphasizing the importance of habitat conservation and protecting core territories for these animals to thrive.
The research, part of the Northwest Boreal Forest Lynx Project, was published in the Proceedings of the National Academy of Sciences and involved a collaboration between UAF, the U.S. Fish and Wildlife Service, and the National Park Service. The study sheds light on the intricate dynamics between lynx and their prey, providing valuable insights that can inform conservation efforts and management strategies for these iconic predators in the boreal forest ecosystem. By monitoring and understanding the traveling population wave effect, researchers and wildlife managers aim to better protect and preserve Canada lynx populations in Interior Alaska.
