Here....ill try to explain this the best i can...
Dogs and many predators have more rods in their eyes, while humans have more cones....rods are kinda like light "picker-uppers" and enable the animal to see very well in low light situations, however the lack of cones in the predator's eye limits the range of color the animal sees.....
look at it like this, this is why i think they are green and red color blind....
the reason YOU see the color of any object is because THAT wavelength of THAT color bounces off of the surface of the object....for exapmle, u see a BLUE ball....the ball is blue because the blue wavelengths (comming from some sorce of white ligth...the sun, a white light bulb) are not absorbs on the balls surfare.... THEREFORE..the blue wavelengths are reflected, and u see blue
coyotes are said to have a green and red color blindness....HENCE, when u shine on a coyotes' eyes (with a white light) they shine green, because they do not pick up the green wavelength, it just relflex off their eye's and enable u to see they green color.....same with a red light...the reason why u can see the eyes so well with a red light is because MOST of the light is red, and they reflect off MORE light for u to see....
...hope that kinda helped....lemme know if i need to elaborate on any part....
Seth