Technical Abstract: Little information is available on the utilization of natural productivity (i.e. zooplankton) by catfish fry. Although fry and fingerlings survive on prepared diets, many nutrients acquired by fry in ponds are most likely derived from natural food consumption. Experiments were conducted to answer the following questions: 1)What is the nutritional value of zooplankton, and 2)Is zooplankton nutritional value affected by fertilization? Samples of zooplankton from each pond were analyzed for proximate nutrients, minerals, amino acids, fatty acids, and vitamins. Fertilized and non-fertilized pond zooplankton were similar in nutritional value; only two fatty acids (C16:0 and C20:4 n-6) were significantly (P < 0.05) different between fertilized and non-fertilized ponds. The zooplankton in this study met or exceeded all nutritional requirements of catfish fry; fertilization of these ponds did not affect zooplankton nutritional value with the exception of pantothenic acid and vitamin B6, which were below the catfish fingerling requirement in zooplankton from non-fertilized ponds. If fertilization practices maintain large numbers of zooplankton, all fry nutritional requirements should be met through the natural biota. Additionally, it may be beneficial to offer zooplankton to fry while still in the hatchery.