If you see a fawn lying alone from mid-May into the summer, its mom probably put it there for safety. The doe will check on the fawn, but will go out to eat and leave the fawn alone for extended periods so as not to attract predators. Unless you know the doe has been killed or the fawn is ill, a fawn is best left alone. One way to make sure a fawn is truly orphaned is to check back periodically from a distance where a mother will not see you.
Even with an orphan, another doe will often take care of the orphan if they are old enough to survive on their own. A healthy fawn that is old enough to chew its cud, a few months old, can often survive on its own if there is food, water, and safety. At this point they are hard to catch.
Spotting a Fawn in Trouble
... One clue to watch for are curled ears... “If the ears are curling like a flower that’s about to wilt, that means it’s dehydrated, and something possibly happened to the mother,” ... Another sign of danger are clusters of ticks around the eyes. That could mean blindness... [from Wild Heart Ranch in Oklahoma]. "
"If the ears are crumple and the deer was standing up and crying. The crumpled ear tips mean that the fawn is dehydrated and mom is gone. The baby needs help!!!" [from Mountain View Wildlife Rehabilitation]
Mother deer will clean their fawns frequently, it reduces their scent. An unclean fawn is another sign it is in trouble.
... While its mother is away, the fawn hides ... sometimes the doe does not return — hit by a car, perhaps. If the fawn is left alone for too long, its ears curl up, a sign of dehydration, and flies may cloud around its uncleaned body, drawing attention... New York Times
... "The fire was moving toward the house," ... He's too young to fully take care of himself even without a fire... he was dehydrated and that he had messed himself," Dawn says. The last part was another clear sign that he'd been left, since mother deer usually clean their babies ... Oregon, August, 2020. Patch.com
Georgia provides this advice: call a permitted wildlife rehabilitator when: You are certain the doe is dead. The doe does not return after 24 hours.
Transport: You can often call your local animal control officer for advice. It is a myth that a doe will abandon a fawn that has been touched by a human. Fawns are routinely rescued by humans while the doe stands by ready to recover her fawn. Wearing a latex glove if available is a good safety precaution. A dog crate or similar is a good method of fawn transport for a very young fawn.
Fawns are milk dependent for approximately the first five weeks of life. If their mother dies, they will starve. Somewhat beyond that age a fawn can survive on its own if there is adequate food and water, and no other threats such as predators or traffic. Goat's milk is a readily available substitute. Cow milk is not a good substitute and can kill the fawn. Milk designed for deer fawns is commercially available. Instructions.
Goat milk or formula can be left out in containers for short times so the fawns can find it. Clippings of plants that deer like can also be left out, such as valley oak, plum, olive and many local plants. See Feeding Deer.
"One of the more important things to remember, when you are feeding, you need to have paper towels or old washcloths. Rub their behind to make them poo and make sure you get them cleaned after. Basically a bottle in one hand and paper in the other and take care of both ends at once." - advice from Jimmy Houston
Baby deer suffers seizures after being wrapped in blankets ... August 3, 2020 United Kingdom, Daily Record
... A baby fawn was fed cow’s milk, which can cause life threatening illnesses to deer ... In another incident a fawn was found by the charity having seizures as a result of being wrapped in dog blankets..,
From the video below: We purchased an Avent Heavy feed milk bottle from Kroger and first of all we used goats milk straight out of the refrigerator at Kroger. The heavy feed bottle is for babies that drink heavy without introducing air to the flow. Then we Googled what we should be doing and found that the Tractor Supply Company had a baby feed that included Colostrum, essential for them to develop. Just like human baby milk, it includes all of the elements they need to grow without mother's milk, not perfect, but does the trick. - September 11, 2019