Which of the following does not imply attempt at conservation?

The option that does not imply an attempt at conservation is "Retraining from the use of the natural resource." This is because it suggests a complete cessation or abandonment of the use of a natural resource, rather than managing it in a sustainable way to conserve it for future generations. Conservation involves using natural resources in a way that maintains their availability and productivity over time, without causing harm to the environment or depleting them beyond their ability to replenish. Therefore, all the other options listed in the question imply an attempt at conservation by putting limits on the size of nets and vessels used in fishing, prohibiting hunting or fishing at certain seasons, and managing natural resources prudently to maintain their sustainability.