My Sam howls! It's super sad too! HAHA! We adopted a little over a year ago and he howls when we come home from grocery shopping, when we leave, if he feels forgotten, if someone is over and he wants to get to know them! Yes, my boy is a howler! I'm quite fond of it actually, but I doubt my neighbors feel the same way!
Lakota is a big time howler/talker. Sometimes she just woo woo's almost like she's winding herself up.
She's a smart one, if Apache has a toy and she wants it she'll start woo woo ing into a full blown howl her tail wagging the whole time as Apache starts to chime in I actually watch her eye up the toy, planning her next move when he's too busy howling to pay attention to her.
When she was younger I watched her just sitting on the deck and start howling for no particular reason.
Fiona has only howled twice. The first time she was on the patio and I was in my office and I ran out to the patio, because I thought she was dying. No sirens, she hears them all the time. During the day, so no full moon. I never figured out why she howled. I thought she was done except on Palm Sunday she howled at church and then was very proud of herself for singing along with everyone else.