Should I raise an abandoned baby bird?
No, you should not do that, unless you have the expertise and the setup needed to give the bird in need of help the best second chance it deserves. Please don’t forget that animals are sentient beings and individuals and not objects for your own pleasure. Sentient beings should be treated with respect and dignity and are not to be used to be experimented with. If you truly care a about the birds welfare, then you better bring the animal to an experienced wildlife rescue or rehabber.
Every bird species has got very specific dietary, but also important unique emotional and social needs, which also means for example that they should not be raised by their own. Year for year we have to take in birds raised on a wrong diet showing a deficient plumage and developmental problems, resulting in a prolonged suffering and sometimes delayed death. Signs of deficiency or even injuries like beak fractures caused by wrong feeding techniques are commonly seen in swifts.
Sadly, we also get frequently involved in problems caused by prematurely released or released imprinted animals, in particular corvids. This happens quite often, because people underestimate the inquisitive, time consuming and sometimes destructive nature of some bird species, and just let them go, when they have got enough. Other bird species, like pigeons, when raised isolated by their own from very young age, will not have a good chance of survival, when released into the wild. Social skills learned by interaction with their own kind, but also the appropriate time provided to adapt to the new environment, are crucial factors built into every short and long term rehabilitation programme of serious wildlife rescues and rehabbers.
Last but not least, you might want to know that intentionally releasing an animal, which is not fit for survival, can be regarded as an offence under the Animal Welfare Act 2006. This may include the release of imprinted animals, animals who are lacking essential social or survival skills or are in suboptimal health, seemingly healthy cat caught animals or exhausted racing pigeons, even if racing pigeons are regarded as pets and not wild animals.