THE world's biggest oil company is desperate not to ruffle feathers.

Two peregrine falcons and their three chicks are nesting at Mobil's Altona Refinery.

The company said staff had embraced the endangered birds and had taken great steps to protect them during a mega-million-dollar refinery redevelopment.

The company plans to ensure the birds have their own, sky-high stack, long before it even starts dismantling the one they have made home.

Workers are proudly sporting new company caps and jumpers featuring the peregrine falcon logo.

They have cleaned up the rough perch atop a tower the birds are roosting in.

And they are busy helping Peregrine Falcon Project volunteers monitor the welfare of the three new chicks that have hatched 120m above the Altona refinery grounds.

Arriving in 2001, the breeding parent pair chose the top of a disused tower in the heart of the refinery to rear their chicks each year.

The falcons have continued to return to the site, successfully raising eight offspring.

Unable to ignore the majestic raptors swooping and soaring through the giant tankers and towers crammed across the refinery, Mobil has included them in its expansion.

"As a company, we have adopted the peregrine's bifocal vision that allows short-term focus on matters at hand while at the same time staring ahead and seeing the broader picture," said refinery acting operations manager Rick Purcell.

When the 2006 proposal to expand the site was raised, the peregrine's presence was included in all plans. For now, they can stay where they are, in a little alcove on a high, wind and rust-ridden antiquated piece of machinery.

They have a view of the city to the east, Port Phillip Bay to the south, and parks and wetlands in between where they easily pick off prey.

Industrial hygiene and safety adviser Nick Ardossi was one of two workers to climb thousands of steep ladder steps, both men carrying 10kg bags of crushed rock material to add to the birds' non-nests.

He helped remove redundant piping in the area and added a barrier so that the helpless chicks wouldn't roll over the edge.

"Peregrine Falcon Project co-ordinator Victor Hurley is advising us every step of the way," Mr Ardossi said.