Installation of beacons to protect mayflies

The Centre for Ecological Research of the Hungarian Academy of Sciences, the Municipality of Tahitótfalu, Magyar Közút NZrt. (Hungarian Public Road Non-Profit Ltd.) and the electricity utility ELMŰ worked together to install a protective system made up of two parts. The first part is the light barrier itself, which consists of two lamps installed on the bridge pillars facing downstream, emitting an intense blue light directed towards the water.

The purpose of the light barrier is to keep the insects that arrive at the bridge close to these beacons, preventing them from flying up to the bridge. The efficiency of the beacons is measured by the extent to which the mayflies are not attracted by the lights of the bridge itself.

Therefore, in addition to the beacons, it was also necessary to adapt the lighting on the bridge by installing energy-saving lamps that cost much less to operate than the previous ones, and whose light intensity can also be adjusted. The municipality of Tahitótfalu assumed the costs of replacing and operating these new light sources.

This will allow us to operate these lamps at a lower intensity approved by the authorities for four hours a day during the three-to-four-week swarming period. In this way, public lighting can be kept at an adequate level during this period from 8 p.m. to 12 a.m., while the beacons can be efficient enough in keeping the mayflies close to the Danube.

Replacing yellow glowing sodium lamps with white LED lamps also improves people's perception of colours. The light barrier was installed on the bridge pillars in Tahitótfalu e second half of April 2019; the modernisation of the bridge lighting was completed in July.