Novel set on a planet colonised by humans being watched by aliens who are being watched by another set of aliens

Question

There was a SF novel I read, probably 20 or 30 years ago, and I don't remember most of the details.

The story centers around a colony planet recently settled by humans. There was an alien race watching the humans, trying to learn more about them, for presumably nefarious purposes. And there as a second alien race, watching the first alien race watching the humans.

The first alien race somehow metamorphosed through various life stages, becoming smaller and longer-lived with each transformation.

I seem to remember one scene in which an extraordinarily competent young human female was searching though an abandoned facility of some sort. The leader of the first group of aliens was in the room, sitting on a lab bench of some sort.

She came in and he froze, trying to appear as being some sort of statuary, hidden among the clutter.

She played along, for a while, then grabbed the cloth he was sitting on, catching him in it and swinging the bundle against the wall, disorienting him long enough to effect his capture.

Answer 1

The Demon Breed by James H. Schmitz

https://www.isfdb.org/cgi-bin/title.cgi?2121

The alien Parahuans had previously tried invading the human space empire, but were thrown back. Humiliated, they invented the ridiculous "Tuvula theory" to salve their egos. It postulates a hidden organization of humans with superhuman powers who caused the invasion to fail.

On the ocean planet Nandy-Cline, a covert team of Parahuans infiltrate and try to find evidence to prove or disprove the Tuvula theory.

Extraordinarily competent human female Nile Etland investigates the floating island the Parahuans are hiding on. While the low class Parahuans are normal sized, the leaders are only one foot tall.

Nile investigates an abandoned building where a Parahuan leader squats on a shelf and pretends to be a statue. She leaves momentarily, but upon returning she noticed the "statue" had moved slightly.

She grabs the cloth the Parahuan is squatting on, imprisons it in the cloth, and whacks it against a rock until it stops struggling