Spectacled bears are polygynous and breed at various times throughout the year, potentially capable of delayed implantation with a variation in gestation time from 160-255 days.
Much of the mating behavior of the spectacled bear remains unstudied, but they are believed to be polygnous.
Males and females mainly come together to mate between the months of April and June. The pair remains together for 1 to 2 weeks, copulating several times during this period.
Mating pairs of spectacled bears can been seen together between the months of March and October, during the time of year when fruit is beginning to ripen. This indicates that, like bears in captivity, spectacled bears are probably adapted to breeding at various times throughout the year.
Andean bears are monestrous, breeding only once per year, and are probably capable of delayed implantation. This would explain the variation in gestation times in captive bears, 160 to 255 days, and the “out of season” births observed in wild bears.