PM Racing Team in Shildon, Teesside, went up in flames on Monday morning with the roof collapsing.
"On this occasion we know it's one family. It could be two families - one family split into two," she said."There has been evidence of breeding on the river. Youngsters have been spotted on the river over the years.
"Beavers only breed once a year and their litters are pretty small - two to three within a litter. So a beaver family could be anything from two adults, to five or eight if you include the young."Last year the Welsh government said it was, as wildlife charities called for them to be released into Wales' rivers.
Dr Robert Needham, from the Beaver Trust, said their reintroduction could bring substantial benefits, describing them as "ecosystem engineer[s]"."What this means is that the sort of habitat modification that beavers can do through damming, building lodges, digging canals - this can create habitats for other species, and they can increase biodiversity," said Dr Needham.
"They can help restore our wetland habitats, which are massively lost throughout Europe, let alone Great Britain.
"They can help alleviate flooding with the dams that they create, particularly in headwater streams, they hold that water back, releasing it slowly. So we see a reduction in peak flow events, during storm events. But this can also be really beneficial to villages and society during summer periods, during drought conditions."Recycling rates hit a new record in Wales in October – with two thirds of council-collected waste now recycled, re-used or composted.
Asked by BBC Wales why the Welsh government was unable to persuade Labour UK ministers to introduce glass, Huw Irranca-Davies blamed the previous Westminster administration and the UK Internal Market Act."It's because of the legislation that was a bequest of the Conservative Party. They really messed it up here a little bit, I've got to say."
He said it had stymied the ability to manage a UK wide-system."It takes something like 1500 degrees to take a smashed piece of glass to heat it up and turn it into something new. The energy costs and the carbon costs for that are significant.