Quite often the Great Barrier Reef's marine environment surprises and astounds those who play and work within its watery depths. The recent sighting of a white humpback whale calf is just one of those occasions.

This amazing photo taken by Mr Wayne Fewings in the Whitsundays recently confirms the sighting and is a reminder that the Great Barrier Reef is home to a wide array of remarkable species of plants and animals.

Great Barrier Reef Marine Park Authority (GBRMPA) Manager Species Conservation Dr Mark Read said sighting such a unique animal reinforces the importance of the Great Barrier Reef and how people out on the water could contribute to our understanding of this amazing ecosystem by reporting sightings such as this.

"The calf was likely to have been born in northern Great Barrier Reef waters and is probably at least a couple of weeks old. We can make this assessment because its dorsal fin is quite erect and the dorsal fin of newborn calves is curved over and takes time to straighten out," he said.

"Nearly all humpback whales are dark on their upper body and this colouration is caused by the skin pigments called melanins. A purely white humpback whale does not have melanin pigments in its skin.

"To speculate on the animals parents is difficult, but what we can say is that this calf is the offspring from two animals that were carrying the white (amelanistic) gene, resulting in this unique white calf.

"From sightings it is believed there is likely to be around 10 to 15 white or predominantly white humpback whales in the east coast population of around 13,000 – 15,000 animals.

"At this time of year humpback whales are on their southern migration returning to Antarctic waters and this animal will be feeding heavily from its mother, trying to put on a good blubber layer to protect it in the cold Antarctic waters."

While out on his boat enjoying the Reef, Wayne Fewings spotted a pod of whales in the distance.

"We were just drifting when I noticed the smaller whale in the pod was white. I couldn’t believe my eyes, and I just grabbed my camera," he said.

"Then the white calf approached my boat, seeming to want to check us out. I was just so amazed at seeing this animal, it made me think how truly astounding the Great Barrier Reef is.

"I feel very lucky to have witnessed this, it’s a once in a lifetime experience."

Dr Read said that approach distances for whales were in place to protect both the whales and onlookers.

Approach distances to whales must be adhered to. Vessels cannot approach closer than 300m to a whale calf. If a whale approaches the vessel, as in this instance, vessel operators must keep the motor out of gear and wait for the whales to move away before motoring away.

The east coast group of humpback whales are a conservation success story with the population brought back from the edge of extinction with numbers increasing each year since the halting of whaling in the early 1960's.

The GBRMPA's Sightings Network receives reports of unusual, extraordinary and iconic species and events which help management and conservation of the Great Barrier Reef. Since 2007, the network has collected more than 5000 reports of over 10,000 creatures and events of special interest in the Great Barrier Reef.