Illuminatus Primus wrote:Ten billion on one planet? For a species supposed to be renown for its reproductive capacities and growth rate? That's pathetic.
Well, it's not as bad as it looks.
For one, Char is not bountiful in resources, it makes sense to keep a low "Standing force" there, since the Zerg fight by reproducing in their enemies home territories, not by sending huge armies over (They did that on Aiur, true, but that's quite the exception), and the larva serve as ready made warrior templates that can be fermented with immense speed.
The numbers also don't say what they count as "Zerg", it could easily not count larva, unique strains (Hunter Killers, Cerebrates), possibly even the flying space based strains (Scourge, Guardians).
It's silly minimalism, but easily rationalized. (Depending on what the rest oif the setting has, we haven't seen new Protoss numbers yet, despite their policing substantial parts of the galaxy)