In California, monitoring marine protected areas can get expensive. Current efforts—which include underwater surveys conducted by scuba diving volunteers—have already cost the state $16 million, and in some places, there’s no funding left. But testing DNA in water samples could provide an effective alternative to more costly methods. KQED’s science and environment reporter, Lauren Sommer, discusses this story and other science news from the week.

Plus, when it comes to their diet, polar bears aren’t so finicky. Would they prefer a fatty ringed seal pup? Yes. But Robert Rockwell, a research associate at the American Museum of Natural History, explains in a new study in PLOS ONE that the longtime “flexible foragers” have incorporated snow geese, eggs, and caribou into their diet as the ice-free season increases in Canada’s western Hudson Bay. Rockwell reflects on the good and bad of polar bears’ ability to face climate change and discusses how the biggest threat to their livelihood might not just be warmer temperatures.