Protect Mustangs™ is against winter helicopter roundups especially because the extreme stress of the whole ordeal weakens the mustangs’ immune system and makes them vulnerable to upper respitory infections such as strangles (equine distemper).
“You can’t chase wild horses with a chopper, trap them in the freezing cold while they are covered with sweat, terrify them for days and expect them to resist an outbreak in a crowded facility,” explains Anne Novak, executive director of Protect Mustangs™. “I’d like to see the mustangs’ welfare come first for once.”
The San Francisco Chronicle reports on the strangles outbreak in Rock Springs: http://www.sfgate.com/news/science/article/Illness-postpones-Rock-Springs-wild-horse-adoption-4217503.php
Here is some information about strangles:
Wiki on strangles: http://en.wikipedia.org/wiki/Strangles