One aspect of island biogeography theory contends that a direct correlation exists between the size of an island and the species richness of an island. We applied this aspect of island biogeography theory to temporary pools. Six temporary pools were randomly selected and placed into three size categories based on the volume of water contained in each. The contents were filtered through a 0.250 mm sieve and retained. Invertebrates were identified, and counted. We found that species richness and the total number of individuals increased with pool size. In addition, the larger pools supported more functional feeding groups than smaller pools. These results were probably a reflection of greater microhabitat availability in the larger pools.