A BAT colony migrating north caused a 20 minute flight delay for the Westpac Life Saver Rescue Helicopter on Wednesday night.
Westpac Lifesaver Rescue Helicopter spokesman Roger Fry said the helicopter was attempting to return to base from Lismore Base Hospital, after completing a rescue at Minyon Falls.
"We were required to stay on the helipad there for a bit of an extended period on (Wednesday) night," Mr Fry said.
"We actually came in after picking up a lady who injured herself at Minyon Falls."
The photo supplied by the Westpac Helicopter (above) shows what crew members experience as they wait at the Lismore Base Hospital during bat migration.
Mr Fry said if they had been attempting to land at this time, they would have had to divert and land at the airport, where a fully equipped ambulance would have been waiting.
"If we happen to be coming in at the time they are migrating out of the tree line and heading north, certainly we would have had to back off and probably go to the airport," he said.
"They're something you can't dodge when there are so many thousands of them flying in the sky at one time."
Even with the prominent bat colony in Lismore, ironically it is not where the helicopter has received the most damage caused by the flying mammal.
"Some have been in areas like Byron Bay, I know we sustained some severe damage down near Woodburn going to a motor vehicle accident there and that was (about) $70,000 worth (of damage) because it went through the nose of the aircraft," he said.
"Fortunately, no one was injured from that but certainly over the years, we have struck bats, some have caused no damage and generally we have been pretty lucky with that.
"But in that particular case in Woodburn, the aircraft was grounded for a period of time so the engineers could inspect it before we could fly back."
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