In the new research we have provided insights into the hidden chemical world of brown bears. How do bears recognise one another? They have evolved a highly developed olfactory system to process odour, enlarged or modified glands to deposit it, and behavioural strategies to supplement its persistence and detection.
Solitary species, such as bears, tend to use scent marks as ‘bulletin boards’ that broadcast long-lasting chemical signals. Behavioural evidence in brown bears suggests that this functions to communicate dominance and attract mates. However, the content of these chemical messages remained unclear. This inspired us to reveal the content of odorous signals that bears leave behind.
We examined scent swabs collected from 12 wild brown bears by the Alaska Department of Fish & Game, analysing the presence, abundance, and uniqueness of volatile organic compounds (VOCs). Samples collected ‘skin-borne’ secretions from various areas on the bears body including the back, flank, cheek, and between the toes; all areas known to be used in scent marking. These VOC profiles varied according to the age-sex class of the bear and its individual identity, indicating that brown bears may recognise these attributes in other bears when they smell a scent mark. We hope this will provide a baseline for further studies to aid in the understanding of social function.
For more information, see:
Clapham, M., Wilson, A.E., Williams, C.L., Sergiel, A. (2023) Brown bear skin-borne secretions display evidence of individuality and age-sex variation. Scientific Reports 13, 3163. https://doi.org/10.1038/s41598-023-29479-y
by Agnieszka Sergiel