World Aquaculture September 2018

48 SEP TEMBER 2018 • WORLD AQUACULTURE • WWW.WA S.ORG S altwater recreational fishing in the United States had a reported economic impact of more than US$ 85 billion in 2015 and is a significant contributor to coastal states through direct expenditures, ancillary industries and employment (National Marine Fisheries Service 2017). There are numerous expenses associated with recreational fishing, including travel, lodging, meals, tackle, licensing, boat/fuel expenses and, in some cases, fishing guide costs. Anglers who pay for guided trips naturally have a greater expectation of success and this often includes the use of live bait. Depending on the location and game fish species targeted, live bait generally includes various types of juvenile marine fishes and crustaceans that are caught locally and provided on a first come–first served basis at marinas and bait stands (Fig. 1). Since these live baits are wild caught, availability of a particular species to anglers is seasonal and dependent on weather and other factors. As a result, demand frequently exceeds supply (Ohs et al . 2017). During the last several years, researchers at the University of Texas at Austin’s Marine Science Institute Fisheries and Mariculture Laboratory (FAML) have been investigating the potential for marine baitfish aquaculture. With near- ly 595 km of coastline and an increasing population, saltwater fish- ing trends in Texas highlight the prospects for baitfish aquaculture near the Gulf of Mexico. Direct expenditures on recreational salt- water angling in Texas were US$ 1.9 billion in 2015, with an overall economic impact of US$ 3.9 billion (National Marine Fisheries Ser- vice 2017). The number of recreational saltwater anglers and guides in Texas is increasing, and consequently, the demand for live bait has been increasing as well. Commercial landings of live baits increased by 53 percent over 8 years, fromUS$ 3.4 million in 2009 to US$ 5.3 million in 2016 1 . Although shrimp are commonly used as live bait, several species of marine finfish are also used. Atlantic croaker Micropogodon undulatus , pigfish Orthopristis chrysoptera , mullet Baitfish Aquaculture: Spawning and Juvenile Requirements of Pigfish Jeffrey B. Kaiser, Cynthia K. Faulk, Kathryn L. Thompson and Lee A. Fuiman Mugil cephalus and mud minnows Fundulis grandis are the primary species sold at bait stands on the Texas Gulf coast (Texas Parks and Wildlife Department data). The most popular marine baitfish in Texas, pigfish and Atlantic croaker, become available to anglers in June each year. They are harvested for three months or so until they become too large for anglers to use effectively. As a result, monthly sales of these fishes can be 10 to 20 times greater during June, July, and August than during March, April, October and November. Marine baitfish are typically caught by trawl, traps or cast nets, depending on species and location. They are then held in tanks and sold live at prices typically ranging fromUS$ 8-10/ dozen. Prices vary by location, availability, and time of year, sometimes reaching as much as US$ 18/dozen, making it a very important and lucrative product for baitfish vendors to carry 2 . Wild harvest of baits can lead to highly variable supply to dealers. In addition, annually harvesting millions of fingerlings of a species from coastal bay systems may have substantial adverse impacts on target populations and the marine habitats and ecosystems they occupy. These impacts may go unnoticed because many baitfish species are not targets of fishery managers. Data from Texas Parks andWildlife Department, for example, show a precipitous downward trend in the abundance of a popular baitfish, Atlantic croaker, since the 1970s. There is enough concern about this that the State of Texas has restricted properly permitted commercial boats to harvest not more than 1500 croaker per day to sell as live bait. Therefore, baitfish aquaculture could potentially help offset the pressure on wild populations while at the same time providing anglers with a consistent, year-round source of a sustainably and locally produced product. In 2012, researchers at FAML began working with pigfish (Fig. 2) as a potential aquaculture candidate. Information on pigfish life history (Darcy 1983) and its potential as a candidate for baitfish FIGURE 1. Bait stands employ a system whereby different colored flags indicate to consumers the types of live bait available at a particular time (Photo: Jeff Kaiser). FIGURE 2. Adult wild-caught pigfish (Photo: Jeff Kaiser).