I know the orioles around my place are not color blind, but they apparently are prejudice of color as they will take the white strings and rarely take any of the red strings for nest building. Even the blue jay came and took the white strings. It is funny to watch them often grab more than one string before flying off to their nesting site as seen in the video I took a few years ago.
Taking Strings
I startled two deer on my lawn this evening when I went outside to put more strings out for the orioles. I can’t seem to keep enough jelly or strings out to satisfy them but when I see the females taking three strings at a time, it is no wonder I can’t cut enough. And of course it is the female oriole doing all the working building the nest and collecting the strings and grass to build it. At least the males could haul the materials to the nest if the female does all the building. It is interesting to spot the red and white strings in the nests.
Strings in Oriole Nest
Watch the Orioles taking strings for building nests.
https://youtu.be/XJVOgYTh03Y&w=640&h=430&rel=0