Have you misplaced your beloved pet's cremated remains, a tattoo gun, an indoor dog toilet, a surfboard, a toaster or your wallet filled with cigarette butts? You might want to call Transperth.

While mobile phones and wallets make up the majority of items working their way through the Public Transport Authority's (PTA) lost and found system, far more unusual items are also left on WA's trains and buses.

In recent months these have included a stretcher bed, IKEA furniture, a prosthetic leg, a gingerbread house kit and a toaster.

Among the 3,262 items found last December alone were a typewriter, a wheelchair, a beach tent, a street sign, a fishing rod, a child's car seat, a watermelon-shaped light, a pool cue, a hair regrowth treatment kit, musical instruments, art prints, a can of baked beans and a large manual trolley jack.

The summer months also saw a spike in the number of bathers left behind, along with surfboards, bicycles, skateboards and suitcases.

'We're left scratching our heads'

PTA spokeswoman Claire Krol said it was mind-boggling how some of the larger or more unique items were forgotten.

"Sometimes we're left scratching our heads. There really is no limit to what kind of things people can forget about," she said.

"We have to assess whether it is something that's actually been forgotten or if it's something that people have unfortunately chosen to dispose of on our system."

It's not uncommon for surfboards to be left behind in summer. ( ABC News: James Carmody )

She said those items ranged from a completed Rubik's cube — perhaps no longer of use to its owner — to more sinister or criminal items.

Abandoned sim cards are a common find, and late last year a bullet was found on a Perth train.

While those items are more likely to be handed over to police, the PTA takes pride in returning other lost possessions that carry significant sentimental value to their owners.

Recently this included an Australian Army Medal, several family photographs and a collection of old English coins.

A recycling gold mine

Just over 40 per cent of items that enter the PTA's lost and found system are returned.

However many others are disposed of or donated to charity if they are not claimed within 30 days.

Each year the PTA donates over 300 kilograms of unclaimed mobile phones to a company that recycles 90 per cent of the material within them.

Some of the lost items are of lesser value than others. ( ABC News: James Carmody )

Unsurprisingly the authority has been the top workplace recycler in Western Australia for seven years running.

Items handed in on Transperth services are taken to the nearest depot or central train station were they are recorded and stored.

Passengers who lose something on a train or bus can visit the Transperth website to register it, while those who leave behind important items including medications, legal documents, or passports can call the Transperth InfoLine on 13 62 13 for priority service.