Laura Simon, field director for the Urban Wildlife Program of the Humane Society of the United States offers the following tips to help homeowners discover whether a wildlife baby needs help.

Baby squirrels: If they fall from a tree being cut down, stop the tree-cutting and leave the babies in the same spot where they fell. If it is cold, put the squirrels on a hand warmer or heating pad on low (using an extension cord) and place a flannel shirt underneath the squirrels so they do not overheat. If the mother does not retrieve them by nightfall, contact a wildlife rehabilitator (log on to the Humane Society of the United States Web site, www.husu.org for a link to a wildlife rehabilitators directory).

Note: assume that any adult squirrels in attics right now are mothers with young.

Fawns: It is normal for mother deer to leave fawns alone for long periods of time to avoid attracting predators to the mother’s scent (the young are virtually odorless and therefore safer without mom around). You should only be concerned and call a wildlife rehabilitator if the fawn is wandering and bleating constantly, or if a clearly lactating, yet dead mother, is found nearby.

Baby rabbits: Like deer, baby bunnies are often left alone during the day. The mother returns to nurse her young twice a day and then leaves so her scent does not attract predators. Only if the babies have been attacked by an animal or injured by a lawnmower (or anything else) should you call a rehabilitator.

Baby raccoons: Raccoon cubs are rarely left unsupervised; therefore, if you find baby raccoons alone for more than a few hours, it is a sign that something happened to their mom and you should contact a wildlife rehabilitator. To help avoid orphaning baby raccoons, do not attempt to trap wildlife. It may be tempting to set a trap for a garbage-raiding raccoon; however, you are likely to catch the mom and leave her babies orphaned. Instead, put your garbage out the morning of trash collection and use animal-proof garbage cans.

Baby birds: It is a myth that if a baby bird is touched by humans, the parents will reject it. The reality is that birds have strong maternal instincts. If you find a fallen chick, gently put it back in its nest. If the nest is inaccessible or destroyed, secure a nest-sized wicker basket close to the original nest. The parents should take over the new nest without a problem. Always watch from a distance to make sure.

Fledgling birds: You may think you see a bird with a broken wing, but many birds can’t fly yet because they are fledglings — birds who have left the nest but still need to learn how to fly from the ground up. These fledglings tend to look like adults but have short tails (their tail feathers haven’t grown in yet). You can tell if their parents are still taking care of them by watching to see if adult birds fly over to feed them and by seeing if there are bird droppings on the ground. Birds “poop” after they are fed, so fecal material indicates that their parents are around and all is well.