Research Project on Red Deer in Eastern Switzerland

Red deer were first hunted using traps and tranquilliser guns, then released again fitted with GPS transmitters.

The findings from the collected movement data show that the animals move far less into other regions than expected.

In eastern Switzerland, red deer populations have increased significantly in recent years. In the Werdenberg region, herds of up to 100 animals were at times observed crossing the main road between Gams and Grabs in the morning and evening, bringing traffic to a standstill.

An increase was also observed in Ausserrhoden and Innerrhoden. Due to the emerging conflicts between wildlife and land use, a cross-cantonal research project was launched to study the behaviour of the population. The animals paid no attention to political boundaries, the final report.

Tranquilliser guns deployed

Among the objectives of the study were observations on behaviour: How long do they stay in one place? Over what range do they move? To find out, individual red deer were fitted with GPS transmitters that reported their positions via SMS. However, the animals first had to be caught.

In countless night-time operations, cantonal wildlife wardens and volunteer helpers succeeded in fitting 46 red deer with telemetry collars, according to the report. Tranquilliser guns and prepared darts were among the tools used. Sixteen animals had to swallow a rumen probe to measure heart rate and body temperature, which then remained in the stomach.

Hardly any long-distance migrations

Among the data subsequently analysed were 450’000 GPS position reports. They show that a large proportion of the red deer in Werdenberg remained in the area throughout the summer, merely moving to higher elevations.

In other regions too, the animals showed “no pronounced migratory tendencies,” according to the report. Supra-regional movements had therefore barely taken place.

New findings also emerged regarding the reaction of wildlife to hobby hunters or mushroom foragers. Red deer employ different strategies in response: some animals remain in cover despite the disturbance and only leave the area after nightfall. Others react by fleeing from a great distance. More on wildlife and on biodiversity.