This Vireo Vireo sp
was photographed at Eisenhower Park, Eastern Harris County, Texas on July 19, 2006; it was singing what appeared to be BWVI-type notes with some REVI-type notes mixed-in...:
In the comparison below, the Eisenhower Park bird is on the left and a Black-whiskered Vireo I photographed at Key Largo, FL in May 2006 is on the right: