Since 1980's, red-bellied tree squirrel has caused tremendous amount of damage to planted Cryptomeria japonica trees at Xitou Nature Education Area. This has attracted significant attention from researchers and managers. More recently, a large number of C. japonica trees suffered from crown dieback. An underlying cause is due to Xitou becoming a major tourist attraction in recent years from increasing number of tourists. In the meantime, tourists feeding squirrels has been observed. This in turn causes the squirrel population to increase that leads to greater crown dieback. At present, it is an ongoing effort to quantify the extent of squirrel damage and its degree. This study aimed at developing under canopy visual assessment of squirrel damage criteria and indicators. The intention is to facilitate field assessment for better quantification on current status of squirrel damage. The long-term benefit is adapting pest management strategies to changing scenarios.