It seems that a family of Nepalese refugees have ten barnyard chickens -- presumably for eggs and possibly for meat. They aren't allowed to keep them in their apartment, so they have stored the chickens in the back seat of their vehicle.
Technically, it's not illegal. The chickens are well cared for. They have plenty of food and water and their area is regularly cleaned. Des Moines allows for urban chicken and have very specific rules when it comes to the size of coops and where they are placed in relation to houses. But there really aren't any rules to regulate car-based coops!
The city plans to follow up with the family, but otherwise has not removed the chickens or intervened.