What news did Gandalf bring the dwarves about Beorn's whereabouts

From the text:

He lives in an oak-wood and has a great wooden house; and as a man he keeps cattle and horses which are nearly as marvellous as himself. They work for him and talk to him. He does not eat them; neither does he hunt or eat wild animals. He keeps hives and hives of great fierce bees, and lives most on cream and honey. As a bear he ranges far and wide. I once saw him sitting all alone on the top of the Carrock at night watching the moon sinking towards the Misty Mountains, and I heard him growl in the tongue of bears: ‘The day will come when they will perish and I shall go back!’ That is why I believe he once came from the mountains himself.”