Nalbuphine, medetomidine, and azaperone use in free‐ranging American black bears and mountain lions in Wyoming

Abstract

AbstractSafe and effective chemical immobilization is a necessary component of large carnivore management and research, but laws regulating controlled substances can limit the use of many drugs by non‐veterinary personnel. NalMed‐A (40 mg/mL nalbuphine HCl, 10 mg/mL medetomidine HCl, 10 mg/mL azaperone tartrate) is a non‐controlled drug combination used to immobilize a number of free‐ranging species, but there are limited published reports of its usage by non‐veterinary personnel when immobilizing American black bears (Ursus americanus) and mountain lions (Puma concolor). Additionally, there are some safety concerns regarding anecdotal reports of spontaneous arousals occurring in large carnivores immobilized with NalMed‐A. We performed a retrospective analysis of capture forms for free‐ranging black bears (n = 34) and mountain lions (n = 7) immobilized with NalMed‐A by non‐veterinary personnel across Wyoming, USA, in 2017 and 2019–2024. Induction (x̅ ± SE) was 10.74 ± 1.16 minutes for black bears (n = 34) and 7.14 ± 1.60 for mountain lions (n = 7). Reversal was 14.21 ± 1.51 minutes for black bears (n = 28) and 10.00 ± 1.26 minutes for mountain lions (n = 5). We used non‐parametric tests (Kruskal‐Wallis, Wilcoxon rank sum) and odds ratios to examine the effect of certain parameters on induction times, redoses, and spontaneous arousals in black bears. Median induction time for black bears injected in their hind leg or rump was greater than for black bears injected in their shoulder (n = 34, W = 79.5, P = 0.045). Six black bears (18%) experienced spontaneous arousals. We recommend avoiding the hind leg and rump for dart placement in bears, and using hobbles and a muzzle for large carnivores when using NalMed‐A in a free‐ranging setting because of the risk of spontaneous arousals.