LIDICKER 1974 Orinda Contra Costa Co., Calif. June 29 - Set out 48 Longworth live traps in order to catch Microtus in O.P. Pearson's "Backyard", i.e., across the creek from his house. Set from ~1700-1930. Sunny, hot day. Used oatmeal for bait but added small chunk of carrot to every other trap. Rolled corn was used for pre-baiting. Sign scarce, but every trap was set in a runway which looked hopeful. In a few cases definitely fresh cuttings or droppings were noted. June 30 Picked up all traps 0930-1130. 7 Mice marked as carrot or non-carrot when picked up. Catch: Peromyscus truei - 1 on a non-carrot trap; released. Microtus californicus - 8 + 1 trap which contained one M was tipped on its side and was gone. 7 of the 9 M. traps were marked as "carrot" but when traps were checked in animal room later, 2 of these had no sign of a carrot chunk; 2 am not sure whether the traps were incorrectly designated or the carrot piece was completely eaten. .. only 5/19 were definitely carrot-baited. Weather: cool night & mostly overcast in AM. Mice were fed by research of Rosamond Bowen.