A computer model analyzing 16 hormones in hair from 130 Alberta grizzlies identified sex correctly 80% of the time overall and 94% among adults. It correctly detected whether adult females had cubs that year in 66% of cases.
Researchers tested a random-forest model against records from grizzlies captured in Alberta between 2008 and 2019. The bears’ sex and age were known, as was whether females were pregnant, nursing or had cubs. Hair reflects a months-long average of hormone levels.
The researchers say hormone readings could complement DNA surveys of hair collected in the wild, giving wildlife managers a fuller picture of bear populations without capturing the animals. They said more mother bears are needed in the sample to improve cub-status estimates.
