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Several books provide an excellent overview of the anatomy and biology of these and other crawfish species. No evidence exists of natural hybrids between these two species. Despite efforts to exclude white river crawfish from many farms, both species will thrive under routine culture practices, and they often coexist in production ponds. They can be easily identified, however, by experienced persons. These two species are often similar in appearance, especially at a young age. Much information is lacking, however, regarding interactions of these two species. Recent research suggests that whichever species successfully produces large numbers of babies first during autumn months will predominate in the pond for the rest of the season. These factors would provide an advantage over red swamp crawfish young that hatched at the same time. Some researchers suggest that later pond flooding dates (late October to November) may favor the white river crawfish because of its tendency to spawn later and its slightly larger hatchlings. No major difference in growth rate and survival between the two species has been observed under typical culture conditions. How these two species interact in crawfish ponds is not fully understood, but one hypothesis is that the red swamp crawfish tends to dominate in more ponds because of greater reproductive potential and a more prolonged reproductive season. White river crawfish are most often found in greatest numbers in ponds that are used to culture crawfish year after year. The abundance of one species or the other may vary among and within culture ponds over time, but the red swamp crawfish most often dominates and is the most desired species in the marketplace. In general, both species are adapted to the conditions found in commercial crawfish ponds, and both respond well to the low input systems of production used in Louisiana. Usually the red swamp crawfish are found in greater abundance in waters with lower dissolved oxygen (DO) content. In contrast, the white river crawfish may grow faster at lower temperatures, and it typically reaches a slightly greater maximum size.

Feeding rates have been found to be greater for the red swamp crawfish at temperatures in excess of 86 F, indicating a possible competitive advantage at higher temperatures. White river crawfish are seasonal spawners, usually spawning only in the autumn in the southern United States. It appears to do better in more nutrient rich-waters than those of the white river crawfish. The red swamp crawfish produces more, but smaller, eggs than the white river crawfish, and it is capable of spawning year-round in the South.