Photographed by Royce Howland in Calgary, Alberta on 12/7/04. Check out more of his work at Howland This bird is interesting in that it shows the red malar stripe of a male Red-shafted (Western) and red on the nape which is only seen in the Yellow-shafted. (Taiga/Eastern). The western is the native population in this area with occasional easterns but there seem to be a fair number of these intermediates which implies that some may be introgressants rather than actual hybirds. The term intergrade would seem a little nonspecific as they do seem to retain rather specific traits. The term "hybrid" implies that the parents were one of each, e.g. a pure Yellow-shafted X Red-shafted. Backcross: to cross (a first-generation hybrid) with one of the parental types Intergrade: to merge gradually one with another through a continuous series of intermediate forms Introgression: Infiltration of the genes of one species into the gene pool of another through repeated backcrossing of an interspecific hybrid with one of its parents.