Activity when wearing HRM vs. "New Activity" in Garmin Fit -- Calories and HR w VFit

I'm trying to get a handle on how Garmin Connect views "activities." I kinda get the fact that when I put my HRM on with my Vivofit, an activity starts that will show up on Garmin Connect. But when I then start a "New Activity" (like a bike ride) on Garmin Fit (on my phone), and then finish that bike ride, I find two separate activities on Garmin Connect-- 1 is called Bike Ride (because that's what I named the ride) and the other is "Untitled" (that's the "automatic" activity that started when I put on the HRM.

The Bike Ride shows the map route I followed, and all the distance, speed, elevation gain, and time, but no HR. The "Untitled" shows elapsed time from putting on the HRM until taking it off. It shows the distance I walked from putting on the HRM to my bike, and all of the heart rate stats.

Both activities show "Calories," and I'm skeptical about both measurements. "Untitled" shows 989 calories burned in 1:49:49, and Bike Ride shows 1277 calories burned in 1:05:27.

So:

• Is there a way to avoid having 2 separate activities created?
  
• Is either calorie burn realistic on a 1 hour bike ride (averaging 13.5 mhp)?
  
• How do I get the HR stats to show up in the "Bike Ride" I created in Garmin Fit instead of the auto-created activity?
  

Many thanks!
Ken