Wednesday, April 14, 2021

[PaleoMammalogy • 2021] Dietary Reconstruction and Evidence of Prey Shifting in Pleistocene and Recent Gray Wolves (Canis lupus) from Yukon Territory

Gray Wolves Canis lupus from Pleistocene Yukon Territory

in Landry, Kim, Trayler, ... et Fraser, 2021.
Illustration: Julius Csotonyi 
• Stable isotopes and dental microwear reveal diets of ancient and modern gray wolves.
• Yukon gray wolves remained large ungulate specialists from Pleistocene to present.
• Yukon gray wolves have remained primarily flesh-consumers.
• Yukon gray wolves transitioned from diets mostly composed of horse to cervids.
• Conservation efforts in the Yukon should focus on ungulate populations.

We investigate if and how diets of gray wolves from the Yukon Territory, Canada, have changed from the Pleistocene (>52.8 ka BP to 26.5 ka BP [±170 y BP]) to the recent Holocene (1960s) using dental microwear analysis of carnassial teeth and stable isotope analyses of carbonates (δ13CCO3 and δ18OCO3) and collagen (δ13Ccol and δ15Ncol) from bone. We find that dental microwear patterns are similar between the Pleistocene and Holocene specimens, indicating that there has been no change in carcass utilization behaviours, where flesh, not bone, is primarily consumed. Based on minimal changes in δ13CCO3 and δ13Ccol values, we find that, over thousands of years, Yukon gray wolves have remained generalist predators feeding upon several large ungulate species. Interestingly, δ15Ncol values suggest that the extinction of megafaunal species at ~11.7 Ka induced a shift from a diet comprised primarily of horse (Equus sp.) to one based on cervids (i.e. moose and caribou). Survival of large-bodied cervids, such as caribou (Rangifer tarandus), was likely key to wolf survival. Although gray wolves survived the end Pleistocene megafauna extinction and demonstrate a degree of ecological flexibility, we suggest that failure to preserve major elements of their current niche (e.G. caribou) may result in continued population declines, especially in the face of increasing anthropogenic influences.

 Keywords: Gray wolf, Dietary ecology, Stable isotopes, Dental microwear, Pleistocene

 Zoe Landry, Sora Kim, Robin B. Trayler, Marisa,Gilbert, Grant Zazula, John Southon and Danielle Fraser. 2021. Dietary Reconstruction and Evidence of Prey Shifting in Pleistocene and Recent Gray Wolves (Canis lupus) from Yukon Territory. Palaeogeography, Palaeoclimatology, Palaeoecology. 571, 110368. DOI: 10.1016/j.palaeo.2021.110368  

... a fascinating new paper on how wolves survived the biological bottleneck of the Pleistocene megafaunal extinctions in Beringian North America by switching their diet from horses to caribou and moose. It was a privilege to work with these scientists through the Yukon Beringia Interpretive Centre to produce a new piece of paleoart to visually support this paper, featuring a pack of Beringian wolves hunting soon-to-be-extirpated horses in the pre-extinction heyday of the huge mammoth steppe environment.