| Popis: |
In my bachelor{\crq}s thesis I have discussed whether movement of a predator dummy reduces the number of birds visiting the bird feeder with food and therefore whether mobile dummies are judged to be more dangerous (more lifelike). Stuffed dummies of sparrowhawks and martens (predators), a stuffed pigeon and a plushy toy (control), situated on an electric ``rotator{\crq}q, were tested. The sparrowhawk and the marten reduced the number of visits to the feeder much more than the pigeon and the plushy toy. Therefore it is clear that the studied species of bird (chiefly tits) are capable of differentiating between individual objects and judging the risk issuing from them. With the exception of an independent analysis for the Great Tit, no difference in the number of visits when using mobile and stationary dummies was proven. However there was a clear trend in general, particularly with the pigeon. Movement by the marten (and also the plushy toy) also markedly reduced the success of individual visits. The static dummy of the predator discourages birds from visiting the feeder as effectively as the mobile dummy, however this may increase the alertness of birds who have decided to visit the feeder. |
