Every May, dozens of yellow garbage bags line Unalaska’s roads. The collection is part of the city’s annual clean-up effort, where residents chip in and pick up litter that’s accumulated over the past year. On this episode of The Exchange, PCR director Jeff Hawley talks with KUCB’s Alexandra Gutierrez about the anti-litter campaign and explains how the weather has turned it into a month long project.

In the second half of the show, UAF researcher Greg Walker discusses use of drones to monitor Steller sea lions in the western Aleutians. Commercial fisheries have been closed in an effort to protect the endangered marine mammal, and millions of dollars have been spent trying to figure out why the stock isn’t experiencing a dramatic rebound. But because of the weather and distances needed to travel in the Aleutians, it’s difficult to study the sea lions and get a definitive answer to the population question. Walker thinks he has a solution to the problem: unmanned aircraft. KUCB reporter Stephanie Joyce sat down with him when he was in town recently, and they talked about how use of drones could make it earlier to observe sea lions.