Still today, the Indian fishing tribes have a ritual which is perhaps one one of the earliest conservation practices.
When fishing for salmon, at the beginning of the salmon season, it was customary to give thanks to the river gods by returning the first salmon caught back into the river, ensuring that at least one salmon would reach its spawning ground up-river and spawn, thereby helping in continuation of the species.
While this was a religious practice, it was based on a basic respect for natural functions and maintenance of the natural processes. Animism?