To claim that anything is balanced is to claim that something is balanced by something else by some kind of control, which cannot be true for Nature.
Nature is the flora, fauna, climate and geography of earth which are all subject to random change controlled only by the laws of physics. The notion that life is in some balance is to claim that there is some organising force other than natural selection, which is the survival of the fortunate.
The idea that there is an existing 'balance' is the result of the fears of the paranoid, for they are dominated by the notion that that their world is so fragile that any change is dangerous; for them Nature is like a house of cards that may easily collapse at any moment, hence the notion of 'a delicate balance'.
Paranoia is the mental disease that finally results in General Paralysis of the insane as the sufferers become too frightened to do anything. If they eat or drink they may be poisoned; if they use a tool such as a telephone or a television, they may be showered in cancer causing electronic radiation; if they use an engine, or light a fire, or burn a kerosene heater they are polluting the air with poisonous fumes as well as using up the planets oxygen supply; etc, etc,..
To environmentalists, everything that involves 'civilized' people — people like themselves — is ugly and dangerous; the only safe things are those their fancy believes are unsullied by themselves so are 'natural' such as 'pristine' wildernesses (The Amazon Jungle, the Sahara, the Arctic, Glaciers, Mountain Tops — all places where people would quickly perish without artificial aids); wild creatures (not those that are useful such as pets, or livestock, or honeybees, but only the useless), primitive savages, trees (forests not orchards), uncultivated fauna, sunshine, wind, etc, etc,..
To believe in 'Nature's Delicate Balance' is to reveal both self-loathing and paranoia, which is lunacy.