An integrative and multi-indicator approach for wildlife health applied to an endangered caribou herd

Abstract

Assessing wildlife health in remote regions requires a multi-faceted approach that may include convenience samplings and the involvement of local communities. Combining data from hunted and captured caribou, we assessed the value of multiple indicators for understanding the health of the endangered Dolphin and Union caribou herd in Arctic Canada. We documented health determinants (infectious diseases and trace elements), processes (cortisol, pathology), and health outcomes (pregnancy and body condition). During a recent period of steep population decline our results suggested relatively good body condition and pregnancy rates and decreasing levels of stress, along with low adult cow survival. We identified multiple determinants of health as potential contributors to reduced survival, including Brucella suis biovar 4, Erysipelothrix rhusiopathiae and lower hair trace minerals. This integrative approach that drew on multiple data sources has provided unprecedented knowledge on the health in this herd and highlights the value of documenting individual animal health to understand causes of wildlife declines.