A BIOLOGICAL BATTLE AGAINST THE THOUSANDS OF GARDEN CHAFERS (PHYLLOPERTHA HORTICOLA) THAT ATTRACT LARGE NUMBERS OF GULLS (LARUS SP.) DURING THE SUMMER SEASON AT RYGGE AIR STATION, NORWAY

• Main Authors: Christian K. Aas, Thomas Olstad, Ola-mattis Drageset, Solveig Haukel, Bjørn Arne Rukke
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Subjects: Key words; biological control agent; Garden Chafer; nematode; Black-headed gull; Common gull; bird strike; Rygge Air Station; Norway 1; Norway; Rygge; Larus canus; Black-headed Gull; Larus ridibundus
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.552.6559; http://www.int-birdstrike.org/Brasil_Papers/IBSC28 WP15.pdf

Seven-eight years ago we first observed very large numbers of Garden Chafers (Phyllopertha horticola) swarming at Rygge Air Station in June and July, attracting large numbers of Black-headed- (Larus ridibundus) and Common Gulls (Larus canus) feeding on these flying beetles. Every summer season since then the Garden Chafers have been present, although in a smaller number in most recent years. The Garden Chafers appear to be the gulls ’ main food during this swarming, since we once found as many as 281 dead chafers inside the belly and oesophagus of one single Black-headed Gull. The large number of gulls at the Air Station naturally causes a serious hazard to the aviation. After first having been refused by the authorities to treat with insecticidal chemicals against the beetles, we started in 2004 to spray the grass areas along the runway with the biological control agent, Heterohabditis megidis (also known as Nemasys H), a parasitic nematode known to attack and control the larvae of the Garden Chafer living in the soil. In subsequent years both the runway and the two taxiways were sprayed with nematodes. The nematodes seem to have successfully controlled the Garden Chafer, as the number of Garden Chafer larvae in the soil