I am partially color blind and cannot track blood for anything. A couple of years ago I purchased some of the bluestar mentioned above but did not get a chance to use it until this year. I shot at a nice buck opening day of black powder and he bucked like I hit him but then after searching for an hour I could not find a trace of anything. I waited until night and went back to the location. Two different colored pills to 4oz of water. I doubled the recipe and never found a blood trail. I then went to where we hang deer when we gut them and sprayed there to see if the bluestar actually works. That stuff lit up the ground very nicely where blood had been. I don't think I sprayed enough when I was looking for a trail. So I can say it does work, to me it's better to have a patient person with you in the day. But if you need to track down an animal and you are alone, I can see the bluestar helping but you might go through quite a bit of it.