How to Blood Trail a Deer Using Basic Forensics

Identify Where the Bullet or Arrow Struck
Take the time to assess the blood that you find along the trail. Is there any stomach fodder, suggesting a gut shot? Frothy blood with bubbles indicates a lung shot. Look for hair and tissue on the ground, and at the relative position of the blood on vegetation. If there's blood on both sides of the trail, the bullet or arrow likely passed through.
Identify Direction of Travel**
Blood drops that fall perpendicular to the ground create round spots, but blood that strikes the ground at an angle creates an oval or elongated drop mark with a tail. When trailing deer, the tail of a drop of blood points in the direction of travel. If drops of blood are perfectly round, the deer was standing still when he bled.

Use the Right Tools
Criminalists use chemiluminescent liquids like luminol and flourescein to find blood stains that might not otherwise be visible. These chemicals react with hemoglobin and make bloodstains glow. Now deer hunters can apply this same technology to searching for wounded deer. Bluestar Forensic's Latent Blood Reagent ($48; comes in tablets that you dissolve in water and spray on the ground where blood might be present. The stain reacts with blood and glows blue. Bluestar is easy to use, and the reaction is so dramatic that this spray can be used for daytime tracking as well as in low light. Small reagent kits are available that can be easily carried into the field with your gear. Each reagent kit includes two packs of two tablets and is small enough to carry in your pack.

Photo by Russell Graves/Windigo Images