The breeding season for brown bears in northern Spain normally occurs around May - June. This year, however, the Fundacion Oso Pardo (Brown Bear Foundation) have video evidence of a female coming into season at the end of August.
This atypical behaviour has been previously documented, on rare occasions, in Canada and Japan. The young female was persued by three males, one of which copulated with her various times. His sperm should still be viable so hopefully she'll add to the Asturian population this coming winter. Reasons for being on heat so late in the year are unclear (ie. no-one really knows) but I suspect it happens with first-time young females before they've settled into a breeding pattern. Experts believe it could be a sign of the species' ability to adapt to climate change.