Not really--it would be the same as if a base was flashing--you'd know that something was going on but until you went there you wouldn't know exactly what.
Lots of battles happen close to the spawn point without it actually being camped.
The only way to reduce spawn camping is to expand the area of spawn. Spawn camping can only happen when the camper doesn't have to swing his barrel much for each shot. If the spawn area was, say, 500 yds from the last spawn it would be simple to eliminate campers.
This option would also reduce the effectiveness of pilots trying to kill upping GV's in base defense tho.
h
(veteran spawn camper)