Missing items found by Arriva include everything from false teeth and umbrellas to musical instruments, walking frames and even a few children in prams.
The company has received more than 35,000 phone calls from customers this year alone, all desperate to be reunited with their possessions.
Keith Myatt, regional marketing and communications manager for Arriva Midlands, said: "If you can name it, we've probably found it on the back of a bus at some point.
"We've had lonesome dogs, live ferrets, glass eyes, prosthetic limbs, handcuffs, and all manner of weird and wonderful bits and pieces.
"While it sounds entertaining on the surface, we know only too well how distressing forgetting things on public transport can be, so we really want to make it easier for our customers to get in touch with us in their hour of need." Mr Myatt added: "Our depots are full of things that need to find their rightful home, and we're determined to help get them there, which is why we are asking people to go online rather than phoning us, as social media really is the most immediate way of alerting our local teams to your despair." Arriva has adopted the motto 'if you love it, don't lose it' and the company is now asking people who have lost items to try using social media before phoning the bus depots.
Mr Myatt said: "With more and more people using Twitter and Facebook as their favoured means of communication, the likelihood of someone finding and posting about something they have found on-board is quite high."
He added: "By using our hashtag of #FindMeArriva we can ensure that our dedicated customer service teams can monitor feeds, respond and hopefully return lost property faster than they ever could previously.
"It cuts out the middleman on the phone and reaches right out into the local community – which is exactly where you need to be with such a tricky task at hand."
Customers looking to locate their lost property should go to facebook.com/arrivamidlandswest or twitter.com/arrivamidlandswest using the hashtag #FindMeArriva.
People can also contact the customer services team via the Live Chat facility on the company's website at www.arrivabus.co.uk/lost-property