In the latest “wolf weekly” report from Ed Bangs at USFWS, Ed wrote: Yellowstone Park researchers report that the summer predation study is going well. Approx 31 kills have been found May-mid through mid-July and they are 20 bulls, 5 cows, 5 calves, 1 mule deer. These data support the results of research done by following tagged elk calves [wolves killed few] and generally, but less so, scat analyses (scat analyses show more mule deer used in summer). Collar locations decrease from one every 30 min now to 8/day starting Aug. 1.
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I should say a bit more about this study. It is very important because all the quantitative data on wolf prey comes from winter observations when wolves generally have more of an advantage, and the ungulate composition in the Park differs somewhat from the summer when a lot of mule deer enter the Park from the Gardiner and some other areas.
Observation of summer predation is much more difficult than winter when the wolves are more easily seen and are more concentrated in the valleys.
In order to study summer predation, sophisticated GPS collars have been deployed on wolves. These collars give the wolf’s position at programmable intervals. It has been every 30 minutes during the early summer.
This allows location of the wolf and probably part of its pack even while in thick vegetation. Those helping with the experiment then hike to areas where the data indicate a probable kill and record the species, sex and any other data available. The results of this summer so far is what Bangs reported above.
While this data could be very accurate, the observations are yet so few, even with last summer’s data, to draw hard generalizations. Moreover, because just one wolf is presently collared, its pack may utilize different prey and at different rates than adjacent packs.
It may take a long time to establish firm generalization unless more radio collars are deployed and more people in the field. Dr. Douglas Smith told me he had been doing a great amount of hiking. Those of us who know how hot it has been on the northern range this summer can appreciate the physical effort this research must require.