mountain lion whistle?

[sdcowboy]

i was sitting in my deer stand watching 2 young bucks starting into my food plot when i heard a whistle like sound. Both deer scattered like someone lit their tails on fire. about 15 min later i heard it again but alot closer. The sound was familiar. I never seen another deer wich was odd. I have been sitting in this stand all year and never have seen less than 20 deer a night. when I got home I checked my foxpro and I listened to the mountain lion whistle and it was the same sound I heard in my stand. My next question is what does the call mean? Is it a female looking for a mate or is it something else. There has always been a few cats in the area but i've never heard them make this sound. I uaually know when one is in the area, because the whitetails disapear. Can I call it in by useing the same sound? any extra knowledge on this would be helpful.
Thanks