Elk begin showing up on Refuge
No immediate need for supplemental feeding yet, say officials
JACKSON HOLE, Wyo. — The latest head count on the National Elk Refuge shows the first arrival of ungulates after a mild start to the winter season has suddenly turned snowy.
According to Eric Cole, senior wildlife biologist with USFWS National Elk Refuge, elk did not begin to come onto the Refuge until December 19. That’s about three weeks later than usual. There are currently an estimated 4,200 elk, 36 pronghorn, and 28 bighorn sheep using the Refuge now.
Record warm temperatures in late November and low Jackson Hole snow accumulations at lower- and mid-elevation areas during the fall likely contributed to late elk migration to the Refuge. Late migration also resulted in one of the lowest elk harvests on record for the Refuge hunt. Only 41 total elk were harvested on National Elk Refuge compared to the 10-year mean of 180 elk harvested.
At least 36 pronghorn are currently using the Refuge, and anecdotal evidence suggests that pronghorn that fail to migrate out of Jackson Hole suffer significant mortality during severe winters,” Cole says.
Pronghorn are poorly equipped to deal with deep snow because it prevents them from accessing forage. They are also more vulnerable to predation.
“No bison have been observed so far this season on the south end of the Refuge, and most bison are well north of the Refuge at this time,” Cole adds.
In recent years late bison movement to the NER has become the typical pattern because bison hunting on the Refuge remains open until the end of January.
“Bison appear to have learned to avoid the Refuge until later in the winter (if they come to the Refuge at all),” Cole says. “We view late bison arrival to the Refuge as beneficial to our efforts to reduce reliance on supplemental feeding. Late bison arrival conserves forage for when it is more critically needed later in the winter and allows us to delay the start of the feeding season.”
Early winter snow and forage conditions
Refuge snow depths were well below average until mid-December, and even with the recent significant storm system, snow pack depths are only slightly above average for late December. Snow pack depth as of December 28 at the Refuge headquarters monitoring site was 8.3 inches (compared to the long-term average for this date of 7.5 inches). The snow is powdery and is not limiting elk access to forage, Cole says.
“I surveyed snow and forage conditions on December 28 and found average available forage at key index sites to be 2,100 lbs per acre. For perspective, at the end of December last year, available forage was 1,900 lbs per acre, and last year we did not begin supplemental feeding until February 3,” Cole says. “Because conditions can change quickly, we will continue to monitor snow and forage availability in collaboration with the Wyoming Game and Fish Department to determine when supplemental feeding is necessary, but there is no evidence to suggest that feeding is necessary in the near future.”
Refuge staff count all ungulates on a weekly basis in a standard 11,400-acre survey area, which roughly corresponds to the southern half of the National Elk Refuge where animals can be readily observed from the ground. The number of ungulates observed in the survey area from December 9-28 are shown in the table below:
