The five-foot-long animal was found roaming the Roscoe Village neighborhood Monday. Chicago police followed and contained the animal in an alley before shooting it. Chicago police officers said the cougar was a threat to the community.
Scientists, on the other hand, are excited about studying the wild cougar.
Cougars are known for traveling long distances, and the animals, at one time, were native to Illinois.
Chicago-area residents may have to become more familiar with the big cats that scientists call 'pumas.'
Brookfield Zoo served as the scientific ground zero for the study of the cougar. Researchers conducted a necropsy on the cougar killed on the North Side of Chicago Monday.
After a chasing the animal through the Roscoe Village neighborhood, police say they were forced to shoot the animal.
"The officers acted properly. They had to take away that threat. No one understands the danger a can cause," said Chicago Police Supt. Jody Weis.
Some neighbors in the area were concerned about shots fired in such a populated area, and some thought the deadly force was not necessary.
"I was horrified. It is inexcusable for police to react the way they did. They should have been prepared with tranquilizers," said Joan Dahlberg of the Chicago Humane Society.
Veterinarian Byron de la Navarre has a special interest in exotic animals. He says a tranquilizer shot may not have worked quickly enough on the cougar and could have made the animal more dangerous.
"He may have had five, 10, 15, 20 minutes to take off, and he might have ended up who knows where," the veterinarian.
At the Field Museum, zoologist Dr. Bruce Patterson shared specimen from 1940. He said the teeth and jaws are the prefect mechanism for a predator to kill. He also said the cougar's Latin name is 'puma.'
"I think this animal that was gunned down was the same animal seen earlier and was looking for meats here in Chicago," Patterson said.
Patterson is eager the learn more about the animal found Monday, and while unusual, he said, the challenge could be for humans and cougars to find a way to live together.
"Pumas are rebounding. They're here to say. It's a cause for both celebration and concern. As a very capable predator, it is a definite threat to people in settled areas," said Patterson.
Scientists are expected to take DNA samples to see if the cougar caught matches other cougars in the U.S.
Cook County officials say Wisconsin officials recently tracked a cougar into Illinois. Preliminary reports showed he was in good healthy prior to the shooting.
A cougar's main food source is deer. There are plenty of those in some Chicago suburbs.