Belted Kingfisher vs. Rough-winged Swallow?

[stype@sccoast.net (Steve Thomas)]

My wife, Barbara, and I walk past a large drainage ditch about 3 to 7 times
per week.  About 8 weeks ago we noticed a male Belted Kingfisher in that
area.  And before we'd fully realized what was going on, he had attracted a
female and they had a burrow in the bank of that ditch.

We've been realtively circumspect in our observations - kept our distance
pretty much.  Still, the male would "rattle" at us each time when we walked
nearby.

About 3 weeks ago we observed about 5 Northern Rough-winged Swallows
perched in the trees not too far from the BK burrow.  Then, a few days
later both kingfishers were very animated - we assumed a raccoon or
something like that was the cause - we didn't walk close to them that day
because we didn't want to add to the fracas.

The next time we walked by (about 5 days later), a kingfisher was in the
area (heard only) - but this time a pair of Rough-winged Swallows were
perched in a tree directly above the burrow holding nesting material in
their beaks.

Today when we passed, the male kingfisher was in his usual spot near the
burrow.  He saw us before we saw him.  The swallows, again holding nesting
material, were in the tree above the burrow.  Both the swallows and the
kingfisher were agitated at our appearance, circling and rattling,
respectively.

We know Rough-winged Swallows will nest in abandoned kingfisher burrows
(according to Hal Harrison), but based on the circumstances of our
observations, it seems plausible that the swallows are in the process of
harrassing the kingfishers.

Since we have no experience observing the nesting behavior of either of
these species, we thought we'd ask if any of the Carolinabirders would be
able to help us accurately interpret the scenario.  So, have any of you
ever seen this before?

Also, could the kingfishers have already been successful in raising a
brood?  We haven't seen any signs of their young, and we're only seeing the
adult male (leading us to assume the female is either on the nest or
absent).

Thanks,
St.

Stephen Thomas
stype@sccoast.net
Aynor, SC