A person was rostered on every day and went to Pilot Bay to do their bit when they found the time, he said.
Three others had also started picking up rubbish along Mount Main Beach recently, and he was aware of some others involved in the Rena clean up who now regularly cleaned further along the coast.
The group would collect up to a tonne of rubbish every one-to-three weeks, which Mr Pettigrew would take to the dump.
Washed up rubbish included everything from dead birds, to discarded plastic and bottles and even pig intestines in a bag once, he said.
The wind direction often determined the nature of the rubbish.
Any injured birds they found were taken to the local Holistic Vets for care.
Summer often saw a lot more rubbish on the beach as bins overflowed and seagulls flew the empty takeaway wrappers around, Mr Pettigrew said.
"On the mornings we know there's a cruise ship coming in we'll go down early."
He hoped people would pick up any rubbish they saw when they were walking around the area.
