Oil spill clean-up efforts are focusing on Matakana Island after reports being received of oil coming ashore there.

Maritime New Zealand national on scene commander Nick Quinn says the Matakana oil is thought to originate from the release of heavy oil from Rena several days ago.

Volunteers clean oil from the rocks at Kulim Park on Sunday. Photo: Maritime New Zealand.

Lighter hydraulic oil being released around the bow section of the Rena appeared to be dispersing naturally.

Reports on Sunday of an oil slick south of the East Cape are confirmed as an algal bloom.

Other beach clean-up operations continuing today are focused on two events at Papamoa Beach this morning and a third at Maketu this afternoon.

'We're conscious as we head back into another working week that people will be busier, but we'd really appreciate anyone that can spare a few hours to pop down to one of the clean up events and help.”

Details of volunteer events today are:

Clean-up at Papamoa Beach, starting at the Hartford Avenue Beach Access, opposite 370 Papamoa Beach Road, starts at 9am.

Clean-up at Te Tumu, far eastern end of Papamoa Beach, starts at 9am. Access is via a gate at the end of Papamoa Beach Road and up a 3km gravel road across Maori land. The gate will be manned from 8.45am - 9.30am, but volunteers are asked to please be on site no later than 9am.

Clean-up at Maketu, starting at 2pm. The meeting point is the Whakaue Marae on Maketu Road.