The New York City-based non-profit avian rehabilitation center Wild Bird Fund took in some cockfighting roosters in December when police busted the individuals involved in the ring. Until this week, the organization has been taking care of 14 of the 30 birds involved, although one bird died from health complications.

This week, the roosters were driven to the VINE Sanctuary in Springfield, Vermont. It is an animal refuge.

These birds have needed a period of adjustment from their former tough-living life. Like fighting dogs, such birds are known to be aggressive at first, because they've been trained to have a strong fight-or-flight response and to attack other animals or anything that comes at them.

"At first they were aggressive with their human handlers, flying out of the cage in attack mode, but they have settled in rather well now," said Rita McMahon, Wild Bird Fund co-founder and director, in a CBS News report. "We have volunteers hold them every day to calm them and get them used to people."

Before heading off to Vermont, they were tested for disease including Salmonella. Clearance allowed them to be taken across state lines to the other refuge. They'll receive further rehabilitation there.

If the cocks catch a glimpse of other roosters, they stamp their feet and spread their wings, "spurs first, ready to attack," as McMahon noted in the report.

In past years, fighting roosters were often euthanized because they were considered unsavable. In 2002, Pattrice Jones of VINE Sanctuary used her graduate education in psychology in combination with awareness of rooster behavior to build a rehab program for cockfighting birds. These days, the method she pioneered is being used in animal sanctuaries around the country. It combines PTSD treatments with behavioral therapy and social learning, noted the CBS report.

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