I work with a veterinarian at a wildlife rehabilitation center, and the great majority of our patients are, as lucie says, injured as a result of contact with the human world. Cat and dog attacks are the primary affront for birds and small mammals; being hit by a car and flying into windows are the main problems with adult wildlife. Tangled in fishing lines and being caught in traps is another common scenario.
Our veterinarian is an expert in wildlife rehab, and also an epidemiologist, so he can carefully judge the prognosis of an animal. I’m pretty tenderhearted, and want to give every critter a chance, but he’s educated me about the larger impact of releasing an unsuitable creature back into the world.
For example: “Finch Eye” is a disease that affects, as indicated, finches and sparrows. It’s spread through individuals at a common feeder, and results in blindness. People bring in affected birds all the time, and it can be “cured” in an individual with antibiotics, but, upon release, can be passed on to others in the wild. So, after some effort at rehabilitation earlier, his policy is to euthanize.
We have an open-door policy; to accept and give treatment to any wildlife that needs care, without charge to the finder. Our success rate is pretty high. But we do take great care in determining if the animal is suffering from simple injury or a genetic weakness.
I’ll add, if you find a wild animal in need of care, please take it to a veterinarian who can either treat it or refer you to a wildlife rehabilitator who has access to proper care. I’ve seen some sad cases of well-meaning folks who have tried to care for critters themselves. It too often leads to an animal that’s imprinted and will never be able to join it’s own species in a normal life, or, worse yet, an animal that’s malnourished to the point of no repair
Whatmove, that’s a nice fable. I have a baby mouse in my care now, 'bout due to be fed. It’s odd, cause I’ve been cranky about mice in my own kitchen. But this one was brought to me for care, and when I feed him through a tiny syringe, he becomes an individual worth the effort. He grips the little nipple and nurses, kneading his tiny paws and wanting to live as much as anyone else. The one thing this job has taught me, after nuturing many, is that each animal is truly an individual, with their own style and expression in life. I didn’t expect that, but it’s a wonderful lesson!