Statistical analysis of fluctuations in red grouse bag data

Area of Science:

• Ecology
• Wildlife Biology
• Population Dynamics

Background:

• Understanding population cycles is crucial for wildlife management.
• Grouse populations have been monitored for decades across the British Isles.
• Previous studies suggest potential cyclical patterns in game bird populations.

Purpose of the Study:

• To investigate the presence and length of cyclical fluctuations in British grouse populations.
• To analyze long-term grouse bag data for evidence of population cycles.

Main Methods:

• Serial correlation analysis was applied to grouse bag data.
• Data spanned 40 to 100 years from various British Isles locations.
• Correlograms were used to identify cyclical patterns.

Main Results:

• Six out of fourteen analyzed series showed a clear 6-year cycle in grouse bag numbers.
• Four additional series suggested cycles of different lengths.
• Only four series showed no evidence of cyclicity.

Conclusions:

• Grouse populations in the British Isles demonstrate significant cyclical fluctuations.
• A prevalent 6-year cycle was identified in multiple grouse populations.
• The findings have implications for understanding and managing grouse populations.