North American River Otters are popping up in places they haven't been seen in decades and nobody really knows why. As we search for answers we discover a trail of fish heads, poop splats and cuddle parties.

Guests:

Katrina Lohan, head of the Coastal Disease Ecology Laboratory at the Smithsonian Environmental Research Center

Alejandra Morales Picard, psychologist at Montgomery College

Rebecca Sturniolo, assistant curator of the America Trail at the Smithsonian National Zoo

Patty Storms &amp; Morty Bachar, otter neighbors

Auld Lang What?

More than 154 million treasures fill the Smithsonian’s vaults. But where the public’s view ends, Sidedoor begins. With the help of biologists, artists, historians, archaeologists, zookeepers and astrophysicists, host Lizzie Peabody sneaks listeners through the Smithsonian’s side door, telling stories that can’t be heard anywhere else. Check out si.edu/sidedoor and follow @SidedoorPod for more info. 