Should you discover something is missing, always be able to provide a clear description of the item.
Having photos of all of your equipment on hand is a good idea.
On the journey home : Ask the Bus Captain to make an announcement in case someone found it or can recall seeing it.
If enroute: Ask the Trip Convenor to contact the lodge to report the loss and enquire if the item was found there. The member is responsible for then arranging its retrieval.
If loss is not discovered until home: Contact the bus company directly, being sure to identify details of the day’s trip - destination, driver. Provide your contact information and member can follow up with the company to arrange retrieval at their site. Timing is essential - call as soon as able. It is the member’s responsibility to arrange to pickup the item.