Blue jay and fox squirrel damage preference among pecan trees

The relationship of eight native pecan (Carya illinoensis) tree characteristics and blue jay (Cyanocitta cristata) and fox squirrel (Sciurus niger) nut damage levels was examined in five southcentral Oklahoma pecan groves during the 1991 and 1992 crop cycles. Each tree's nut length, width, total mass, kernel mass, per cent kernel, distance from the grove's edge, trunk area, and canopy area were regressed on wildlife damage levels at that tree. The relationship between fox squirrel damage and distance from the grove's edge was consistently negative when the data from each grove were analyzed separately by year. The correlation was significant (P < 0.05; R(2) = 0.29-0.46) in five of the 10 grove-year combinations tested. Combining the data from all groves and years also indicated a significant relationship (P = 0.0001, R(2) = 0.12) described by the regression equation: squirrel nut damage m(-2) = 5.876 - 0.065 X tree distance (m) from grove's edge. This suggests that increasing distance between a grove and surrounding woodland may reduce fox squirrel depredation of pecans.