MELBOURNE Airport may be forced to shut later this year if the impending locust plague is not controlled.
Australian Plague Locust Commission director Chris Adriaansen said if high density swarms emerge near the airport later this year, there could be disruptions to flights.
"It's something we will have to keep a close eye on once locusts get to the swarming stage," Mr Adriaansen said.
Mildura Rural Council mayor Glenn Milne said Virgin Blue halted jet flights in and out of Mildura earlier this year when locusts descended on the regional centre.
Cr Milne said turbo-prop aircraft were not affected, so the airport did not close.
Victorian plague locust commissioner Gordon Berg said the plague in 1973-74 saw Tullamarine Airport close.
Mr Adriaansen said the 1973 Melbourne Cup and Boxing Day cricket tests had been delayed due to locust swarms.
"Locusts can become a more widespread social issue," he said.
A Qantas spokesman said the airline was operating on the premise flights would continue, but would depend on the severity of the swarms.
However, Qantas did not have serious concerns at the moment.
Mr Adriaansen said even the best control campaign was likely to see about 20 per cent of locusts escape pesticide applications. He said even that was "still going to be shed loads of locusts".
Victorian locust authorities have turned to previous big plagues for critical lessons.
The state's biggest plagues were in 1934 and 1973-74.
Mr Berg said in 1973-74, locust eggs survived over winter and hatched in the spring of 1973.
"There was widespread breeding over the (following) summer so that by autumn of 1974, we still had locust swarms in Victoria," he said.
"We had damage in irrigation areas over the summer and we saw widespread egg laying in the north of the state."
Mr Berg said the populations collapsed due largely to an unusually wet winter that caused lush growth. He said there was also some parasitism and diseases of eggs, which helped limit numbers in late 1974.
