The effect of scarers on the presence of starlings (Sturnus vulgaris) in cherry orchards

Abstract A study was carried out on the behaviour of starlings (mainly juveniles) which are pests in cherry orchards where they eat ripening fruit. Observations on 17 radio-tagged starlings during the cherry-picking season showed that most individuals continued to feed in the orchards on consecutive days despite the use of a variety of scarers. Distress calls of starlings played through loudspeakers were effective in that they temporarily scared starlings, but birds returned during the periods when no distress call was played. However, starlings no longer responded to these distress calls after the period between days 7 and 13. Captive starlings could not maintain their weight on a diet of cherries and the maximum daily intake was 25 cherries, amounting to 1·5 times the bird's own weight. The length of time spent in the orchards by radio-tagged birds (on average 2·8 hours) was far longer than the time needed to eat 25 cherries. It is concluded that the present arrangement of scarers was inefficient and that the netting-in of an orchard would be more effective.