Can geese adjust their clocks? Effects of diurnal regulation of goose shooting

Since 1994, goose shooting in Denmark has only been allowed from 1½ hours before sunrise to 10 a.m. (since 1997 until 11 a.m.). The aim of the diurnal regulation was to provide autumn‐staging and wintering geese with more undisturbed feeding opportunities, and hence to extend the length of their stay in Danish haunts. A field study was carried out during 1994–1997 to investigate the effects of the regulation on the behaviour and site use by geese, focused on greylag geese Anser anser and pink‐footed geese Anser brachyrhynchus at three important Danish sites. Data from earlier studies and monitoring schemes provided baseline information. In one study area with low shooting intensity, greylag geese did not change the timing of their morning departure from the roost to the feeding areas. In two sites with higher shooting intensities, they gradually delayed their morning departure from the roosts over the years. In the two sites with intensive shooting, greylag geese redistributed themselves during the daytime, albeit in small numbers. In the site with low shooting intensity, greylag geese depleted the waste grain resources, the preferred food. In the two sites with higher shooting intensities, the geese left while food was still plentiful. Pink‐footed geese did not change their roost flight departure and only marginally redistributed themselves during the daytime. In sites where shooting‐free areas were established, numbers of greylag and pink‐footed geese immediately increased. The weak reaction by the geese to diurnal regulation was not due to a lack of behavioural flexibility in response, but reflected the fact that staying and adjusting to the diurnal regulation was a less attractive option than moving on to less disturbed sites. In conclusion, the diurnal shooting regulation did not achieve the intended management objectives.