For a better harvest, 

 Today and tomorrow 



The problem: scientific information needed so 

 fisheries managers can make better management 

 decisions 



Are North Carolina's fishermen overfishing the state's 

 stocks of hard clams? Is the opening date for scallop 

 season timed so that fishermen make the best harvest? 

 Are valuable estuarine nursery areas adequately protec- 

 ted? These are the kinds of questions fisheries managers 

 face every day. Managing wild stocks of fish for the good 

 of all, managers must look out for today's harvest as well 

 as tomorrow's. To do so, they need to know more about 

 the resource as well as about the people who use it. 



The research: studies that will look into the 

 biological, economic and social aspects of the 

 state's fisheries, providing managers with a clearer 

 idea of how their policies affect those they manage 



Nothing is more important to tomorrow's fisheries 

 than estuarine nurseries. Kenneth McKaye and David 

 Colby want to know what factors in the nursery affect 

 the survival of young fish. And, they want to learn what 

 makes an estuarine nursery a nursery. 



Using laboratory and field experiments, McKaye and 

 Colby will study why fish choose certain habitats as nur- 

 series over others. They want to know how factors such 

 as predation and water-movement patterns affect the 

 fish's selection of a nursery, and, in turn, how that selec- 

 tion affects their chances for survival. 



In answering these questions, McKaye and Colby 

 hope to learn what factors distinguish a nursery area 

 from other parts of the estuary. And arriving at a better 

 definition of a nursery could help fisheries managers keep 

 those nurseries productive. 



McKaye and Colby won't be the only scientists prob- 

 ing the estuary; Charles Peterson and his team of 

 graduate students will be there too, prying into the 

 secrets of two mollusks — the clam and the scallop. 



Fishermen are harvesting five times more hard clams 

 today than they were in 1976. Managers are worried that 

 this intense harvest will eventually take its toll on adult 

 populations. And fewer reproducing clams could spell 

 fewer clams for tomorrow. Using methods he developed 

 to determine the age of clams in an earlier Sea Grant pro- 

 ject, Peterson will be testing clams to see how harvest 

 pressures have affected the clam's ability to replenish its 

 numbers. 



Peterson and his team will also be testing methods that 



could be used to increase hard-clam abundance. During 

 his first project, Peterson found that under predator- 

 exclusion cages in sandy areas the number of baby clams 

 that set and survived increased 20-fold. Peterson wants 

 to test the cages in other habitats and determine their 

 economic feasibility. If it is cost-effective, caging could 

 become an alternative to clam hatcheries. 



Testing seed-clam survival rates is another of Peter- 

 son's goals. Some fishermen plant seed clams (baby 

 clams) on leased bottomland to assure themselves of a 



Photo by Nancy Davis 



Jim Easley 



ready harvest. But a sure payoff can sometimes end in a 

 pile of crushed shell if predators invade the beds. Peter- 

 son will be working with seed clam's to see what combina- 

 tion of clam size, clam density, planting schedules, 

 habitat and anti-predation measures are needed to max- 

 imize seed-clam survival. 



Questions about another valuable mollusk, the bay 

 scallop, will also occupy Peterson in the estuary. As an 

 annual crop, the bay scallop fishery could be eliminated 

 with a single harvest. Good management is crucial to the 

 fishery's survival. Management plans call for a limited 

 season with managers setting opening and closing dates 

 to maximize the fishermen's harvest. 



But present management schemes don't take into ac- 

 count bay scallop natural mortality rates, perhaps falling 

 short of their goal to maintain stocks and maximize the 

 fishermen's harvest. Peterson will study bay-scallop mor- 

 tality, concentrating on the fall and winter months. 



All fisheries research doesn't have to be done in the 

 laboratory. Jim Easley, Ann McDermed and Tom 

 Johnson do their work at the computer. They are using 

 computer programs to test new fisheries' management 

 policies before those policies leave the drawing board. 



Business administrators use computers everyday to in- 

 crease their company's profits or efficiency. Why not ap- 

 ply the same technology to fisheries management? 



