1963 Krebs trapping on his Tilden area left to mine says on april 3: "230 mic caught on control 1 acre ± this week, est. 3/4 of population caught .:. 250/acre ± 50" [need live traps + tag-release] april 30 set 48 Sherman below Ninety Way at 6 p.m. lots of runways. may 1 right clear at 7 a.m. traps held 14 microtine, 15 Rethro, 6 mice. may 3 Krebs reports: "~ 240 ind. microtine on Tilden. control 1+ acre this week, est 3/3-3/4 caught." may 6 analysis of scats picked up along fire road below Ninety way (closest to Inspiration Point) about 2 1/2 miles, 3 Rethro, 1 Rabbit, no toge. looked for scate along wood #--- up Big Spring, canyon in Tilden to crest, then took along another fire road about 200 yds N of the stream bottom; stopped at several places where grass etc were lush and saw only a few runways. no places where the habitat was being abused by microtine, nothing like the concentration on my area and Krebs'area. Only a few scats also, more fresh. (-2) at 4 p.m. set Tilden grid, every site = 100 traps, saw 1 redtail and 0 cats. Weather warm nuggy. 3 men on lower half of 35-acre surveying for golf course!! may 7 light rain. Runtraps at 7 a.m., no cats. 37 mice, 8 Rethro, and 1 big deerbunties. Left traps set at some places. at 4 p.m. traps held 39 mice. Doubled up on traps (2 at every other station: A 2, A 4, etc), still 98 trials no cats.