Apr 9 Barton Creek, 4 mi. SW Austin, 500 ft., Travis Co., Texas flew to a liveoak 20 ft SE and I watched them frage there. Mate gave notes si vu vuut from time to time, a sort of subdued scold type note; also teet - or sang from time to time. The two worked on terminal twigs (liver and catkins new) and on bark of larger limbs. ? with duller crest and creamy cheeknut forehead. What I took to be contour feeding took place once with intensified chuk vu vuut of (?) bird (actual feeding screened from my view). Twice occasionally would be fraging and without warning or evident external stimulus would drop downward or dart 3 to 6 feet lower in tree to a new perch - fraging would be continued as tho without interruption. I walked down the slope along a fence which trended compass E. Near the bottom I heard twice (soft calls) but could not see bird (I think 2 were present). This was along edge of cliff cut by a tributary in area where I had seen thornase on my way out yesterday. I approached from streambottom but saw no sign of the birds. At 7:55 I started N in canyon bottom. 8:06 song N of stake labeled "90" - thornase in junipers with a few elms and liveoak at stake "78" seen -- --- very fast and peter peter (rarely). Bird flew southerly at 8:15 changed direction when it saw me flying instead to elm east. Chee chi vu vuut vuut vuut scold flat not the piercing stucriculate note (this at 8:15) bird flew S and sang as before from there. Silent at 8:22 - song resumed 4 minutes later farther S. Tried to stalk this bird but