Generally speaking, Shad are a great forage species for Largemouth Bass, but they aren't ideal for every fishery.
While there isn't a hard and fast rule about how big your fishery has to be, in most circumstances, we find it is hard to establish a sustainable broodstock of Shad in a body of water smaller than 5 acres and that typically they do better in a much larger body of water. Shad are pelagic, meaning they school in open water, prolific consumers of phytoplankton (microscopic one-cell plants) and zooplankton (microscopic animals), and highly fecund. Despite their small size (the average adult Threadfin will only reach 5 inches), in smaller ponds, they can create excessive competition for resources with juvenile game fish and adult bait fish - like Bluegill.
Because Shad are pelagic, they spend most of their time schooling in the top five feet of the water column. If your pond is too clear, they are exposed to threats from predation. Additionally, since Shad are filter feeders it is important to maintain a healthy plankton bloom throughout the growing season to support and sustain a threadfin shad population.
Threadfin and Gizzard Shad spend their time in open water. In fact, it is their offshore schooling that creates such an exciting topwater fishing experience. Bass typically lie in wait for their prey, which they generally hunt as individuals. However, the schooling behavior of Shad causes the Bass to modify their feeding habits, consuming several of the small forage fish with each bite. Without sufficient habitat, such as the Honey Hole Canopy, stocking Shad supplementally to your fishery might be a great way to add variety for your Bass, but you'll have a hard time establishing a broodstock.
Understanding the established fish population in your fishery is another key component in deciding to stock Shad or not. As we've already discussed, because of their prolific nature, Shad can create competition for resources with juvenile game fish and adult bait fish. You need to have the right ratio of prey to predator to insure the Shad don't impede the recruitment of juvenile bass to your trophy-class population. Understanding the overall health of your Bass population will help determine if you have too many, or too few Bass to justify the supplemental stocking of Shad. Additionally, unless you have a significant population of big bass, we almost never recommend stocking Gizzard Shad. They can grow to 8 inches, making them just too big for the "average" largemouth, causing even more competition for resources with your broodstock Bluegill.
If you have any questions on stocking your pond or the fish we have available, stop by and see us at our office in Gainesville, Texas, give us a call at (940) 668-2573, or email us at askapro@pondking.com.