Fern, born to Jewel on January 19, 2012, had a full litter of Clover, Clyde, and Cletus (1 female, 2 males) in 2016. All survived through family break-up at about 1.5 year of age.
Ferns cub
Then Fern skipped a year when cubs were expected in 2018 and had a single male cub Carlin in 2019 that was seen with her on May 26, near the beginning of mating season, but did not survive. There was no cub with Fern when she was seen a month later, after the mating season, on June 29 of 2019. There is no way to know the cause of death, but when a single cub is lost during the mating season
Fern I suspect it was like the Lily and Hope story—that one cub cannot suckle enough to prevent ovulation, leaving the mother with conflicting drives to both mother and mate with mating taking precedence for long enough that the cub often dies (unlike Hope).
Now in 2020, she has another single cub. The picture of Fern calling the cub down is at a birch tree, which is a little unusual. Cubs much prefer to climb trees with strong, rough bark, like in the pictures of the cub from another day in a white pine.
This brown cub that is still of unknown sex makes us think that Rusty, a brown adult male was busy last year—as he is again this year. This brown male has been seen in several places in a 5 mile diameter area. Pixie’s cubs are brown, too. And Donna lives in that circle. 
Ferns cubHowever, I might be jumping the gun a bit in calling them brown because some cubs that start out dark brown molt into black or almost black fur by September.
We’ll see how this single cub does through the remainder of this mating season, but I suspect that if Fern kept it this long that it will make it. Always guessing and then learning.
Thank you for all you do.
Lynn Rogers, Biologist, Wildlife Research Institute and North American Bear Center