Latest Yellowstone den news
All the packs probably denned. Some pups have been spotted.

5-17-2004

Past updates on Yellowstone wolves this spring suggested that the Slough Creek Pack, the Agate Pack, Mollies Pack, the Yellowstone Delta Pack and the Swan Lake Pack might not have denned. The other packs clearly had denned.

Now it has been confirmed that the Swan Lake Pack denned at its traditional den site. The Slough Creek Pack too did den, and one pup has been visually observed outside the den. The Delta Pack denned near one of its traditional sites in the remote Thorofare, and Doug Smith saw the alpha female, 126F come out her den and look up at the spotting plane. Nine Delta wolves were near the den.

Mollies Pack denned and the Agate Pack seems to have denned in its traditional, somewhat remote, Antelope Creek area den (at least they dug a big hole and the pack was nearby).

That the Geode Pack denned is now old news, but it seems to have had a double litter. Eleven pups have been visually observed!  Eleven seems more than the small 70 pound, alpha female 106F would be able to produce.

The U-Black female and big wolf 194M have 5 pups. 255F lost her litter and returned to the Druid Pack.

Only one male wolf in the Gibbon Group has a radio collar, but visual observations of these wolves by the Park staff and by tourists seems to indicate they are localized in the Gibbon area.

In other news, the two wolves fitted with the new, most advanced GPS collars, had their location frequency upped  to 48 location points per day (every 30 minutes). These data are remotely downloadable. What was not anticipated was that one of the 2 wolves fitted with these collars would den, Druid 376F. This was a bit of a disappointment, but perhaps more data will be obtained about den site behavior than was anticipated.

The purpose of these new GPS collars is to get a detailed picture of where wolves are in the summer when they are more difficult to observe, and especially to determine what they eat and the kill rate. Almost all the information on kill rates is wintertime data. Many people think this overestimates the annual kill rate if the raw winter figures are simply scaled up to a full year.

In the winter, Yellowstone Park wolves kill very few deer.  There are almost no wintering deer inside Yellowstone Park. In the summer there are deer in the Park, and it is thought that some packs might gain substantial summertime nutrition from deer predation.