the reason why either animal is prone to bacteria contamination is the pysiology of birds and the way they're slaughtered. there's a much higher chance of piercing the internal organs of fowl when they're butchered, thus spreading bacteria more easily than other animals.
as far as pink goes, duck tends to be a darker coloured meat, somewhat more reddish than chicken, so even when it's reached it's safe internal temp the meat will still retain some pink. chicken tends to "whiten" up much more quickly. so colour isn't really a good indication of safety.
it a similar thing to cooking buffalo meat. if you try to cook all of the pink out of a buffalo burger, you'd be better off getting your skates and a stick because you'll have a first class hockey puck, rather than a burger.
in nomine patri, et fili, et spiritus sancti.
beidh ar la linn.