Spawning is the process of fish and other aquatic animals releasing eggs and sperm into the water for fertilization. BREEDING is the act of producing offspring from two parents, and is a key part of the spawning process. PROLIFIC refers to the ability to produce offspring in large numbers, and is often used to describe species that are able to reproduce quickly. FERTILE describes the ability of an organism to produce offspring, and is related to PROLIFIC in that it is a measure of reproductive success. PRODUCTIVE is a term used to describe the ability of an organism to produce offspring in large numbers over a long period of time.