About one month ago Australian Bat Clinic expert Trish Wemberley told how some of the region's biggest bat colonies were emptying as Queensland's warmer winters keep melaleucas flowering longer and in new locations.

On Wednesday, the Sunshine Coast's popular Goat Island bat roost at the mouth of the Maroochy River also suddenly emptied, causing the Sunshine Coast Council to cancel popular tourist cruises.

The Sunshine Coast's Landsborough colony has also completely disappeared earlier than expected and there has also been a marked decline in grey-headed bats on the Sunshine Coast in 2016.

On Thursday Trish Wemberley said her very recent research showed major increases in bat roosts at both The Gap and at Mt Ommaney in Brisbane's western suburbs.

"I have just discovered that The Gap has a huge colony of grey-headed flying foxes," Ms Wemberley said.

"So, there is one spot we have found them," she said.

A second bat roost at Mt Ommaney near the suburb's golf club has also greatly swollen in size to have around 100,000 flying foxes.

The Mt Ommaney colony includes black, greys and little red flying foxes.

The cold snap in the weather about two weeks ago here had a major impact on baby little red flying foxes.

"We had that cold snap about two weeks ago, didn't we," Ms Wemberley said.

"Well we ended up with hundreds of dead little flying red flying foxes," she said.

"And we have about 45 in care."

Ms Wemberley said The Gap's grey-headed bat colony was a new colony, with local residents saying last season's original colony is now "20 to 30 times" its original colony size.

"We knew about the one at The Gap about a year ago," Ms Wimberley said.

"It had a few bats in there, but wow, they are right down along the river and there is a huge camp of flying foxes."

The Maroochydore River's missing Goat Island's bats were predominantly greys, with some black bats.

Raeleen Draper who manages Sunshine Coast's flying fox program, said Goat Island's mangrove and banksia trees was normally a "winter colony" for bats.

"And they were all gone yesterday," Ms Draper said.

"Usually you get four to six weeks that they are there in winter, but this time it was barely three."

She noticed that mangroves recently stopped flowering.

Mr Draper agreed with Trish Wemberley's theory that unseasonal flowering of melaleuca trees during the warmer winter was a factor in the bats moving.

"The melaleuca flowering this year has been so strange," she said.

"It has been going since February and it is still going and the bats have been moving around."

Bats feed on the flowering eucalypts.

The Sunshine Coast has 22 bat roosts, with nine roosts monitored by the Sunshine Coast Council.

Ms Draper said most Sunshine Coast bat roosts continually "emptied out in April", with bats returning in September.

She said she had also noticed major changes at Sunshine Coast bat roosts at Coolum, Maroochydore and Landsborough.

"The other massive change that we have seen at our colony, which is normally occupied by greys (bats), is at Landsborough, which has been empty for five weeks now," she said.

"I have absolutely no idea for the changes at this roost."

"But something is happening out there and we definitely need more research."

The University of Melbourne has recently received money to co-ordinate 17 flying fox research projects over three years, including work on the Sunshine Coast, Ms Draper said.

The research is called Resolving Human and Flying Fox Conflict in the face of environmental change.

"So it is very exciting because the Sunshine Coast Council will be partnering them in their research."

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