From 1950-2000, local black grouse populations have steadily diminished in Manchuria and northeastern China by about 39%, with birds being most affected (and possibly extirpated) in the Jilin Province. Though the exact causes for local declines remain largely unclear, habitat loss and excess hunting have played a part in the overall reduction. Additionally, climate change might have modified the range and densities of black grouse. Shifts in their location, however, can happen concurrently with the depletion over decades, so short-term research projects may not provide much proof of driving forces behind population alterations.