This National Geographic article describes how feeding bread to ducks is harmful. Among the items listed as safe to feed to ducks it lists corn. Does this mean that cornbread is an acceptable alternative to regular bread?
Cornbread may contain wheat flour as well as corn meal. Both are processed cereals and so should not be given to wild creatures.
In addition cornbread probably contains some of these ingredients:
Tempting as it might be to feed wild creatures, they should only be fed food they would normally eat. In addition, once you start feeding them the habitat will be able to host more creatures than it would support naturally. So if you stop feeding them, many will die.
In a park there may be many random people feeding the ducks, who come and go, and so the duck population may stabilise.
But when feeding wild birds in your garden in winter you must continue as they will be relying on you.
It is generally considered a bad idea to feed wild animals, both for the animals themselves and for humans.
- Animals can become dependent on the handout,and unable to fend for themselves, or take natural paths to food sources at certain times of year.
- Humans generally don't have food that wildlife would eat, and human food may not be healthy for them.
- feeding them can cause them to bunch up in ways that are not normal, spreading disease, and/or polluting water or landscape with an overabundance of feces.
- Animals expecting to be fed may cause damage to habitat that would not otherwise occur.
- habitualizing animals to human presence, like houses, vehicles or roads can cause them to come in conflict with those things (i.e. get run over on the road), and cause injury to the animal as well as damage to property.
- Feeding one kind of animal will often attract another type (e.g. feeding the squirrel might attract a bear)
- animals that you are ok with with not be ok with other humans they come across, resulting on conflict.
- Threat responses can be triggered around food, and cause conflicts with humans or other animals.
- Cause the animals normal behavior to be altered, making it appear diseased, and ultimately destroyed.
Here are some references: