I dunno how thick the woods are back East, but out here in the Northwest the woods can eat up sound like that Japanese kid eats hot dogs. /ubbthreads/images/graemlins/wink.gif
I once took my howler, and an FRS radio, and walked down the road away from camp, howling every few hundred feet, and having my brother at camp radio whether or not he could hear it.
I didn't make it 800yds, before it was no longer audible in camp, once I climbed up to a high bare spot above the road I could barely be heard again through the trees between us.
It could be that the coyotes are much less vocal, but it could also be that they are harder to hear too.
I have the advantage or being able to drive to the open sagebrush "west" in just a few hours... And I can tell you howling there, and here are completely different in terms of response (both physical and howled response).
I think the woods coyote needs to be less vocal... there is plenty of food to go around, so territorial howling is going to be unecessary, mating howls may or may not be needed as they will scent mark their areas anyways, and they too have probably found trying to "yell" to get ahold of one another isn't very effective for them either in the thick trees.
Then there is security... I can tell you I don't much like the idea of howling sometimes, knowing in my woods a lion could be within yards (or in yours a wolf), and I could never see it.
And I am sure the coyote knows as well as we do, these larger predators would kill them as competition... he ain't gonna sing his song 'til he knows who's who, and where they are.
I imagine the coyotes around here thinking "stupid fool... doesn't he knows Tom has been hanging around all day!?!" lol
Krusty