Sleepy Holly peers outWith the temperature a balmy 28F, Holly got up and looked out of her den, but the deep snow seemed daunting. Just seeing Holly fuels the excitement of getting to know her better in a month or so.
Juliet and cubWith warmer temperatures the last couple days, Juliet was active without the cubs screaming from the cold. They provided us and the Den-Watchers with good views—and data on eye opening.
Juliet's 3 cubsMatson (1954) reported that a cub’s eyes were fully open at 40 days of age and its littermate’s eyes were partially open on that same day (February 12) in Pennsylvania. The only other report we know of is by Gary Alt (1989)—also in Pennsylvania. He wrote, “None of 27 cubs younger than 36 days old were observed with eyes opened, and all cubs older than 46 days had opened eyes. Three cubs were observed with partially opened eyes when 36, 38, and 46 days old. The opening of eyes apparently is a gradual process with variation between eyes of the same individual cub as well as between cubs of the same litter. The state of opening was considerably more advanced for one eye than the other of one 46-day-old cub. Two different litters (36 and 38 days old), of 2 cubs, each had 1 cub with partially opened eyes while the eyes of the second cub were closed.”
Juliet’s cubs are expanding the observed range of variability. On February 22, Den-Watchers excitedly reported eye shine from one of Juliet’s cubs. At only 30 days of age, its eyes were open a slit. We wondered if all of Juliet’s cubs’ eyes would open early. Nope. The 2 other two cubs lagged and are just now opening their eyes.
Yesterday, we saw all three cubs on their 43rd day of life. One’s eyes were fully open. Another’s were still closed, and the eyes of the third were partially open.
Juliet and cubToday, with all the activity, we saw them again. The one that had both eyes closed yesterday had one eye partially open. The one with partially open eyes looked about the same.
References:
Alt, G. L. 1989. Reproductive biology of female black bears and early growth and development of cubs in northeastern Pennsylvania. Ph.D. Dissertation. West Virginia University, Morgantown. 116 pages.
Matson, J. R. 1954. Observations on the dormant phase of a female black bear. Journal of Mammalogy 35(1):28–35.
JulietOn another subject, the bears have been through brutal cold this winter. The bitter cold hit on December 6, 2013. From then until the end of February (85 days), temperatures dropped below zero on 72 nights, compared to only 46 and 29 nights during that period in the previous 2 winters, respectively. No wonder Holly burrowed deep in the straw.
Juliet backed into latrineWe’re still putting our thoughts together on the hearing while we feel thankful for what the attorneys did and your donations that made their work possible. Throughout the hearing, it felt good to know so many of you were there in spirit while supporters who lived nearby were there sitting behind us and giving us encouragement whenever there was a break.
Thank you for all you do.
—Lynn Rogers and Sue Mansfield, Biologists, Wildlife Research Institute and North American Bear Center
All photos taken today unless otherwise noted.