DO NOT TRY TO RAISE INFANT OPOSSUMS IF YOU DON'T KNOW WHAT YOU ARE DOING! THEY WILL DIE!!! Contact an opossum rescuer immeidately. (Also, it’s illegal to care for an opossum or have one as a pet if you don’t have a special certification).
Please administer first aid to the orphans following the instructions below BEFORE you call a rescuer. (Instructions on how to find a rescuer in your area are lower on this page in RED).
IF YOU HAVE FOUND AN OPOSSUM, PLEASE DO THIS IMMEDIATELY
If the infants are very tiny, less than three inches long, or naked, get them to someone experienced IMMEDIATELY. The longer they are out of the pouch and not nursing, the lower their chances for surviving. They require an experienced hand to survive the crisis of being orphaned.
The worst dangers to the orphans are chilling and dehydration. It is CRITICAL that they be gently warmed. The easiest and safest way to do this is to wrap them in cloth and hold them against your body. Once they are no longer cold, they may be placed in a box/basket or plastic container. This box should be placed on top of a heating pad set on LOW. Layer cotton cloth or fleece in the bottom of the box. The infants are placed on top of these layers, and covered with more layers of cloth. Alternative heat sources are plastic bottles of warm water, heated rice or bean bags, or hand warmers. Always protect the infants from being in direct contact with the heat source- they will get too hot. Monitor the temperature frequently to make sure that the babies are just slightly warm to the touch. Do not use terry cloth because of the danger of the little threads getting wrapped around toes or tails. T-shirts, sweat shirts, or blankets cut into small squares work great.
Young opossums, like other small mammals, need stimulation to eliminate. This is always true for pouch babies. Older opossums should also be manually stimulated, because, even if they would normally be able to eliminate on their own, when they get dehydrated they can retain both urine and bowel movements. It is much better to be safe than to watch an infant die from a ruptured bladder. Do this EVEN IF you have seen urine or feces produced- they may not be emptying completely.
Potty the baby in the following manner:
Hold him in one hand, feet down and close to your body, and allow him to hide his head between your palm and your body. Use a wet, warm tissue, soft cloth, or cotton ball and gently stroke the genital area towards the tail until urine or feces or both is produced. Have clean tissue ready, because once he starts to go, you should not stop stroking until he is empty. Remember that what you are imitating is the mother's tongue, and that is the sort of frequency and pressure that you are seeking. Be sure to wipe toward the tail so as not to introduce fecal bacteria into the genital tract.
Note the color of the urine (dark, medium, light) to report to your contact, and help you assess his hydration.
Now is the time to get on the phone and locate someone knowledgeable about opossum infants, so that you can take the infants to them.
CLICK HERE TO FIND AN OPOSSUM RESCUER IN YOUR AREA
Note: Other species that have no fur can be mistaken for opossums and vice versa. It is unusual for hairless opossums to be found anywhere except in the mother's pouch. Infant opossums do not squeak or mewl, their only cry is a sneezing sound (CHH! CHH!). If they are pink, their mouths may be closed except for a small opening directly under the nose. If the pinky animal that you have found was laying in the yard, or has a high pitched cry, or opens its mouth wide, it is probably not an opossum, but these first aid instructions will aid any small pinky mammal until you can get help.
If the babies are older and are well furred, you may try to give them fluids to keep them hydrated before you transfer them to the experienced caregiver. Pedialyte is a product available in grocery stores that is used to rehydrate human infants. Dilute it with distilled water 1 part to 2 parts, warm it to body temperature, and offer slowly with a dropper. Even small infants have the ability to lap, and some will suckle. Do NOT force it, as the infant could inhale the fluid!! Just one drop of liquid entering the lungs can mean a protracted death for the baby. Be careful.
The mother opossum's pouch is specialized environment. Opossums need very specific care, and it can be quite different in many ways from that of other small mammals.
ONCE AGAIN. DO NOT TRY TO RAISE INFANT OPOSSUMS IF YOU DON'T KNOW WHAT YOU ARE DOING! THEY WILL DIE!!!
You cared enough to rescue them; now please care enough to take them to a rescuer that will ensure they have every chance to survive to be healthy adults.
Please don't think that you can wing it or "figure it out" when it comes to rearing this wonderful animal. Opossums certainly need all the friends they can get, but you can't guess at, or assume much, about the correct care. This web page is provided to increase the orphans' chances of survival until it can be given the needed foods and medications. Yes, you can learn to care for opossums, but you can't learn it from a webpage, email, Internet mailing list or forum, and you can't do it on your own. Opossum rehabilitators are sorely needed all over the country; contacting N.O.S. and your local wildlife rehabililtators is the way to start learning this wonderful vocation.
If it is impossible for you to work with someone experienced directly, you must at least make telephone contact! Although email and websites can give supplemental or emergency information, they are not a substitute for direct interaction with a person with experience. Remember that ANYone can put up a webpage, and we are seeing increasing numbers of cases where opossums have been harmed by improper (even harmful!) information found on the web. An important note regarding formulae: We are also seeing infants presenting with hypocalcemic episodes when they have been fed various "name brand" formulas. Untreated hypocalcemia can quickly result in death in infant opossums! Remember that a photo of opossum on a label does NOT qualify it as a suitable milk replacer.
Please, please don't wait until the opossums that you have rescued are sick or dying before you contact someone knowledgable; if you wait until they are sick, the chances to save them are greatly decreased.
(This information was taken mainly from opossum.org)