Wes's post reminded me of something I've had some thoughts about for some time.
Urine stained tying materials. I can believe that one of the components of a Tups Indispensable gets it's yellow color from urine. Then we come to the famous/infamous 'pink' fur from a vixen fox for the equally famous Hendrickson fly. I know, I know, it is supposedly from a fox taken during a time of estrus. I'm still not convinced. If blood would stain/dye any predator's fur, none of them would have any white fur. I haven't done any real scientific research. But I have obsrved that my dogs can make their white fur/hair turn the same shade of 'pink' when they lick various cuts and scrapes they collect from pursuring game thru thorny thickets and/or barbed wire fences. My theory is that the saliva is doing the staining in both instances. Now who wants to collect some saliva from a female fox. Or not as valid, but a lot easier, a dog, male or female. For my part, I'm willing to take the 'pink' hair that my dogs have produced and see if I can tie a nice Hendrickson. Tongue, almost in cheek. Gary
