Tracking at night requires a different technique. Take careful note of your surroundings, and use your compass or GPS for marking bearings before you start your recovery effort. You don't want to add getting lost to the challenge of game recovery in the dark.
Depending on the type of flashlight or lamp you use, blood will actually glow because of its phosphorus content.
In some locations, predators may be a problem if game is not recovered quickly. Game that's left overnight can attract coyotes, bears, or domestic dogs.
Be sure to check local and state game laws regarding recovery of game after dark. It may not be legal to have your bow in your possession when night tracking with artificial light. It may be legal to use dogs to help you track wounded game.
Before you start nighttime recovery efforts, use a Global Positioning System (GPS) to mark your bearings to avoid becoming lost.