Hatchery bass making a difference in Florida
Monday, April 30, 2012
Media contact: Bob Wattendorf
Fisheries biologists often refer to a three-pronged approach to fisheries management: habitat, fish and people. To develop and sustain high quality recreational fisheries, all three components need to be addressed.
Most biologists stress that habitat – from water quality and quantity, to the amount of structure, including aquatic plants and resulting forage – may be the most critical. However, managing fish, which is often seen as stocking more or “better” fish, is often the first thought of anglers. Meanwhile, the people aspect, which includes engaging the public in resource stewardship, outdoor recreation and harvest regulations, is often the most visible approach.
Lake Talquin, an 8,800-acre reservoir near Tallahassee, is an excellent example of the Florida Fish and Wildlife Conservation Commission’s (FWC’s) three-tier approach. The reservoir, which was formed by damming the Ochlockonee River for hydroelectric generation, is known as a crappie and bream fishery. Historically, steep embankments provided a limited zone for bass to spawn and where submerged aquatic plants could grow. Those plants help shelter fish eggs from currents and provide places for baby fish to hide and feed.
Consequently, FWC biologists implemented a three-phased approach to manage largemouth bass there, beginning in 2000 by planting shoreline vegetation, stocking hatchery fish and implementing an 18-inch minimum size limit on black bass. Today, native bulrush, much of which was transplanted by FWC programs, comprises 5 percent of the shoreline. The goal is 7 percent to 10 percent.
Since then, the FWC has stocked more than 700,000 advanced-sized (3- to 4-inch) hatchery bass. These fish are difficult to raise to this size in large numbers at hatcheries because of their cannibalistic nature and the pond space and time required. However, these stockings, using fish from the two FWC freshwater hatcheries (Blackwater in Santa Rosa County and the Florida Bass Conservation Center in Sumter County) proved immensely successful.
Timely releases of 2- to 3-inch hatchery bass, reared in ponds on natural food, resulted in 17 percent to 40 percent of the young fish collected in Lake Talquin from October 2000-2003. Three years later, hatchery fish comprised about 25 percent of the angler catch from bass tournaments on Lake Talquin. These fish were identified using a metal-detecting wand to determine the presence of a coded-wire tag that biologists implanted in the hatchery fish before stocking. (See MyFWC.com/Fishing, and click on “Freshwater” then “Stocking” for a video of the tagging process.)
Since 2010, at least 15 hatchery bass weighing 8 to 11.5 pounds have been recaptured from Lake Talquin. Since only about one-fifth of the stocked fish were tagged from 2000-03, many more fish could have been harvested, or caught-and-released, by anglers who didn’t know they were holding a hatchery-spawned bass. Supplemental stocking and aquatic plant management activities, as well as the 18-inch minimum length limit may have contributed to the trophy largemouth bass fishery on Lake Talquin.
Previous stocking efforts typically involved Phase-I fingerling bass, which were pond-reared in hatcheries on zooplankton to a size of about 1 to 1.5 inches. But, the fish were vulnerable to predators.
Unfortunately, raising enough 3- to 4-inch bass in hatchery ponds to supplement a significant number of lakes in Florida is cost-prohibitive. As a result, the FWC is experimenting with two alternate approaches. The first uses new artificial diets and a method the FWC developed to train fingerling bass to consume it, rather than each other, so they can be grown in intensive tank management systems more cost effectively. The other involves tricking adult bass in hatcheries using light and temperature to spawn earlier (or later) than they would in nature. This allows pond-reared, Phase-I bass to be stocked when there is abundant forage, such as baby threadfin shad.
Charlie Mesing, the FWC Habitat and Species Conservation biologist responsible for helping manage Lake Talquin, and other FWC scientists experimented with the latter approach recently. Their 2008 scientific publication concluded that stocking low numbers of 3- to 4-inch pond-reared bass prior to the threadfin shad spawn, which occurs around mid-May in Lake Talquin, can result in significant fishery improvements.
Largemouth bass are not the only fish stocked in Florida’s fresh waters by the FWC. Anglers can learn more about the species and locations stocked by visiting MyFWC.com/Fishing. Recently, signs have been posted at boat ramps where stockings have taken place. The signs have a QR code, which anglers with smart phones can scan to learn more about stockings that took place at their locale.
During 2010-11, more than 4 million freshwater fish were placed in public waters. The FWC is on schedule to meet or exceed that goal for 2011-12 and continues to study ways to make stocking more successful, while enhancing habitat and using appropriate regulations to ensure Florida remains the Fishing Capital of the World.
– Rick Stout and Dave Yeager contributed to Bob Wattendorf’s column.