Individual study: Testing of acoustic methods (broadcasting of bird distress and alarm calls) to deter grey herons Ardea cinerea from fish farms, North Rhine-Westphalia, Germany
Behlert R. (1977) Phonoakustische Methode zur Vergrämung von Graureihern (Ardea cinerea) in Fischzuchtanlagen (Acoustic methods to deter grey herons (Ardea cinerea) from fishfarms). Zeitschrift für Jagdwissenschaft, 23, 144-152
This study is summarised as evidence for the intervention(s) shown on the right. The icon shows which synopsis it is relevant to.
Scare birds from fish farms
A trial at a fish pond in western Germany in 1976 (Behlert 1977) found that broadcasting the flight call of a grey heron Ardea cinerea during daylight caused herons standing near the pond to take off and deterred flying herons from landing. However, at dawn trials, the majority (ten of 12) of herons were not deterred from landing. Preliminary trials had revealed that distress calls were more effective at scaring herons than heron alarm calls, combined heron and other bird alarm calls or a white-tailed sea eagle Haliaeetus albicilla call.