Major North American cities are full of large cockroaches. Given their numbers and relatively short lifespan, there must be staggering quantities of cockroaches dying in a city every day. However, I never seem to encounter their carcasses in cities.
I notice a fair number of dead roaches indoors, which actually surprises me since you would think that there is more thorough cleaning and pest control indoors vs. city streets. The number of dead roaches I see indoors seems about consistent with the number of live ones.
However, outdoors I see a lot of live roaches, and hardly any dead ones. Most carcasses I notice are mechanically damaged and near heavy traffic areas, so most likely stepped on by someone who was walking by. But what about roaches dying of natural causes (or disease/poison)? Are there animals that scavenge the carcasses very efficiently (ants? birds?)? Do the roaches like to run away and die in isolation? Do they just not die naturally very often, and usually get hunted by a predator?
Note that I am asking specifically about city cockroaches, in mostly concrete areas.