Answer:
It is a tool for keeping population in equilibrium state.
Step-by-step explanation:
One female egret represents that she is a tool for the continuity of its breed or species because female egret lays eggs and reared their offspring in order to maintain its generation in that salt marsh area. These female egrets are the essential part of this salt marsh ecosystem due to the ability to control the population of other organisms through feeding behaviour. These female egrets helps in maintaining the equilibrium of the ecosystem by constantly producing baby egrets.