Facebookista poiminta sivulta Voyageurs Wolf Project. Käännös tiivistetysti.

Kauriiden kunto riippuu talven ankaruudesta, mm. lumen määrästä. Jos kauriit ovat heikkokuntoisia, susien on helppo metsästää niitä. Ne tappavat silloin enemmän kaurisyksilöitä, syöden vain parhaat palat. Keväällä ne saattavat palata haaskoille, kun saalistaminen on vaikeampaa.

Kun meillä siis vähennetään kauriiden talviruokintaa, sudet ja ilvekset tappavat runsaslumisina talvina kenties entistä enemmän kauriita? Vähälumisina talvina puolestaan on saalistus vaikeampaa, kauriit syödään tarkemmin heti kaatamisen jälkeen ja haaskoja ei juurikaan jää maastoon.

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Documented the first kill of our winter field season yesterday—this one a deer that was almost entirely consumed by the Bug Creek Pack in a short period. The only things left were hair, some bone fragments, blood, and rumen contents (the black/brown bits you see in the photos).

We could not determine the sex or age of the deer because everything was consumed. This level of consumption is pretty typical, though in some instances we might find the lower jaw, a portion of the skull, or parts of a leg or two. Still, little is left.

Generally speaking, the only times wolves do not completely consume the deer they kill is when either wolves have been scared away from a kill, or when winter conditions are severe. In the former instance, wolves may abandon a kill when people show up at a recent kill that the wolves were still feeding on. Human presence can cause wolves to avoid that area (this is not always the case but can happen). In the latter instance, severe winter conditions—mainly long-lasting deep snow—lead to deer being in very poor physical condition and therefore highly-vulnerable to predation. And thus wolves can easily find and kill deer, something that is not typically the case. During such times, wolves may not consume every iota of a kill but instead eat parts of the carcass and then go find another deer to kill and partially consume.

This ”partial consumption” behavior is likely due to: 1) wolves being in a food surplus, which reduces the drive to spend time chewing up every morsel of a deer to extract every last bit of sustenance (why gnaw on a backbone or try to crack a femur with your teeth when you can easily just go kill another deer?), and 2) wolves taking advantage of a brief period when deer are easy to catch and kill. Wolves are like every other animal—squirrels, birds, beavers, foxes, mice, and the list could go on and on—in that regard. When the getting is good, they obtain as much food as they can.

Often wolves return to these partially consumed carcasses in spring when deer are much more difficult to catch, and wolves are hungrier. Wolves will spend substantial time during spring gnawing on the bones to get the marrow, eating any rotten flesh or hide that remains, and so forth.

Right now, our winter has been very mild and we have about ~6 inches of snow. These mild conditions mean most deer are in pretty good physical condition, and difficult to kill. Thus, we are not surprised to see complete consumption of kills and expect this to remain the case unless we get a lot of snowfall in the coming months.