Preheat the oven to 350 degrees. Place the ancho chiles on a sheet pan and roast for 6 minutes. Meanwhile, boil about 2 cups of water. Remove the chiles from the oven; when cool enough to handle, snip off the stems and slice lengthwise to remove the seeds. Transfer to a small bowl and add just enough boiling water to cover. Let the chiles steep in the water until soft, about 30 minutes. Transfer the anchos, with their soaking water, to a blender along with the chipotles and process until very smooth.
While the chiles are soaking, dry the bear meat with paper towels, then salt and pepper it generously. Heat the olive oil over medium-high heat in a Dutch oven or other heavy pot. Add the meat, in batches, and brown it on all sides for about 10 minutes per batch, then transfer to a plate. Add another glug of olive oil if the pot goes dry for the second batch.
Reduce the heat to medium and add the onion. Cook, stirring occasionally, until soft and translucent, about 8 minutes. Add the garlic and cook, stirring, for another 2 minutes. Stir in the cumin and oregano, cook for a minute, then add the chile purée and bring to a boil. Return the meat to the pot along with the beef and chicken stocks. Add the blueberries, then bring to a simmer.
Simmer, uncovered, for about 1 hour and 45 minutes, or until the meat is very tender. Add the black beans and salt and pepper to taste, then simmer for another 10 minutes or so.
Serve hot, garnishing the chili with a dollop of sour cream and a sprinkling of cilantro as desired. Serves 6