Rosie vs. Cascade Rosie vs. Rocky Mountain elk.

[STIKNSTRINGBOW]

I agree about animals being more vocal when they cannot see each other.
I also have noticed that they don't go around screeming at each other.
My experiences are much like Okanagans.
When communicating the elk are only loud enough to get their message to the intended recipient, not acting like a loud drunk, being loud for no reason.
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Did you know an elk can make all the hair on their rump stand up when alarmed? (much like pronghorn)
Not all forms of communication are vocal.
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In my experience and opinion, Roosevelt elk travel in closer proximity to each other, and merely communicate within their small area, unless they are broadcasting their location in search of other elk.
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In the area I hunt, I hear more bugles in early August than in September.
I think this time is when young bulls are actively searching for a herd that won't run them off.
Bull/cow ratios are targeted to be 12+/100, which averages out to one bull with ten cows, this seems to be consistent with my observations, small scattered herds with only one bull, yet when I see 12, or more cows, then I see 2-3 bulls.
These larger herds are rare in my area, and usually the focus of local hunters.
This could cause the elk to be a little call shy, not only from bad experiences with hunters, but also competing with older, more aggressive bulls.
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I personally get more responses from raking and chuckles than I do with location bugles.
Bugling often gets silent bulls sneaking in, unless I am right in on the herd.
I also have noticed that Roosevelt seem to come in slower than RM, often I have given up on a set-up, only to spook one of those silent bulls.

[cougforester]

I agree with the chuckles being a very good technique for calling Rosies. But I've found that once you get in the "red zone", 50-100 yards and threaten them, they come in like a freight train ready to fight.

The bull we killed last year covered 80 yards in about 3 seconds when we got set up ready to brawl. But, then to your point about silent bulls, we were just finishing up taking pictures and starting to get cutting, another bull had snuck in silently and finally got our wind from about 10 yards away and busted. Had no idea he was there. So we had both behaviors clearly exhibited within about 20 minutes of each other.

[blackveltbowhunter]

IME, vocalization and or vocal responses are driven exclusively by 3 things, mood, pressure, and BTC ratio. Its like a triangle, hot bull, good BTC, low pressure. Both species will be sounding off a lot.

 My observations have been that Aggressive approach or the commitment phase is driven by mood and habitat. Bulls that grow up in areas where they can't see until very close have been much more aggressive to not only bugles but noise in general.

   Although we will likely never fully know why; a couple reasons come to mind. One might be the sight factor itself. Because they can't see they have to get close to confirm target. Because they have no distance, they come in ready to fight because they have no choice. Another is that elk that live in more vegetated areas with prevalent feed and water don't travel as much unpressured. This creates a smaller home profile and that bull is less likely to randomly cross paths with other bulls during day  to day activity.  He doesn't need to bugle as much, but when he does its for a reason. On the opposite end of the spectrum, bulls who have herds that need a lot of movement just to carry out the day to day often cross paths with other bulls. Location bugling is huge for these guys, and its not unusual to have hundreds of locate bugles thrown around a canyon and bulls never budge. When herds collide that's when things get real, but typically these bulls have grown up in areas where they use their eyes to confirm the other senses. That sense slows them down, and he may be very wary unless in his home turf.

  I know when I began hunting areas other than dense westside it started a sharp learning curve. But I still base my tactics primarily on terrain and vegetation. Species doesn't even come into play for me. I have had rosies bugle all day long across a clear cut canyon, and I have had Rockies charge through a hundred yards of pine to kill me once I was in his bedroom. In general I think rosies habitat predisposes them to being more aggressive, vocal but less big bugles, and conversely Rockys often need the big noise and use it to avoid trouble. But both species cross over all the time.

   
 

[Old Man8383]

WDFW did genetic profile work ups of some elk in SW in the mid to late 1990's.  Don't know how large the sample size was.  WDFW had proposed relocating elk from the Chehalis River basin West of I 5 to other areas and it was questioned if they were Roosevelt's or hybrids.  Of the elk WDFW tested from a variety of studies and I think from field check stations in SW Washington all elk tested West of I 5 were Roosevelts.  Those tested East of I 5 were all hybrids except in the Coweeman drainage where the elk tested were Roosevelts.  Surprisingly from areas that historically were known to have elk move across I 5 there still were no hybrids West of I 5.

Since there are no absolutes in this type of thing, its safe to say there are still probably few if any hybrids West of I 5 and there are probably few or no pure blooded Roosevelt left East of I 5.