THE welcome spring rains have caused an early outbreak of mosquitoes in the Seaford area.

Residents living near the wetland alerted Melbourne Water, the managers of Edithvale and Seaford wetlands, to the problem.

An inspection found the recent rain had provided breeding grounds for a larger number of mosquitoes.

Larvae have started to breed in shallow pools within the Seaford wetland, a few weeks earlier than in other seasons.

Melbourne Water says it is not a problem at Edithvale because there is a larger expanse of water and the ripples caused by wind drown larvae.

At Seaford, the wetlands abut homes, Seaford North Primary School and Patterson River Secondary College.

Melbourne Water contractors have started a spraying program that is expected to bring the Seaford mosquitoes under control within about three weeks.

A Melbourne Water spokesman said: "Our spraying program targets the smaller larvae but will not act against more mature larvae about to hatch or the mosquitoes already in the area, and that's why it will take about three weeks for the spraying to have an impact.

"In the meantime, we encourage residents to inspect their yards and remove or cover stagnant water [in buckets, etc] and use a personal insect repellent with DEET, to provide the best protection.

"Results of the spraying will be monitored, with further spraying undertaken as required through the season, until April.

"As part of our mosquito management program, Melbourne Water inspects our wetlands weekly in breeding season to best manage outbreaks."

The spray used targets the larvae only and is not harmful to people or pets, the spokesman said.

Melbourne Water senior aquatic scientist Eddy Tsyrlin said traps had been set to catch mosquitoes at Seaford.

As a precautionary measure, the samples would be sent to Department of Primary Industries laboratories for testing for Ross River virus and Murray Valley encephalitis virus.