Bears Like Devil’s Club Berries

For anyone living along southeast Alaska’s coast, the fact that bears like devil’s club berries is a no brainer. Laurie Hart and Taal Levi from Oregon State University demonstrated for the first time that bears not only eat the berries, but they are the main reason devil’s club grows where it does. They are the major seed dispersers of devil’s club in coastal Alaska (their plots were near Haines). This article is a fun read because the authors not only sampled bear manure piles but set up motion detection cameras and swabbed the remains of berry clusters to search for DNA trails from brown and black bears (and even distinguished between male and female bears!)

Brown bears eat the berries first in the season (starting in mid July), then the black bears come in (early to mid August). Birds amounted to about 20% of the feeding and included robins as well as Swainson’s, hermit and varied thrush. When bears chomp on a cluster of devil’s club berries, they devout more than 70% of the fruit. Female bears devour more fruit than males of both species. Both species ate about 30 berries per second or about 100,000 berries per hour! Factoring in the density of bears, they estimated bears disperse over 200,000 seeds per hour per square kilometer! Wow! After the bears have their lunch, additional dispersal occurs from small mammals and squirrels. The next time you have to hack you way through a devil’s club thicket with a machete, blame the bears!

Devil’s club and bears

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