A Case History in Fishing Regulations in Great Smoky Mountains National Park: 1934–2004

Abstract

Since the establishment of Great Smoky Mountains National Park (GRSM) in 1934, fisheries managers have utilized about every angling regulation in the toolbox to manage salmonids. Our objectives here were to summarize the regulation history of GRSM and determine whether regulations affected the age or size structure, growth, and population dynamics of wild populations of rainbow trout Oncorhynchus mykiss within GRSM. Data inconsistencies made data comparisons among regulation periods difficult; however, where feasible, comparisons revealed similar population dynamics among periods. The number of legal rainbow trout per kilometer of stream ranged from 215 to 885 throughout the 70-year study period, regardless of regulation. There were no statistical differences in rainbow trout relative stock densities (RSDs) on Little River among the 1930s, 1950s, 1980s, and 1990s, despite liberal regulations prior to 1960. Rainbow trout mean length at age data indicate no differences among populations for age-1 to age-4 rainbow trout. There also was no statistical difference between the age structure data for age-1 to age-4 rainbow trout collected in 1945 and 1993. Water quality data indicate that GRSM streams are naturally acidic and infertile, which results in populations that exhibit fast growth with high annual mortality rates. As a result, we determined that regulations provided no discernable effect on wild rainbow trout populations in GRSM. Most regulations were put in place for social reasons and were never evaluated over long-term periods (>5 years). Abiotic events, such as droughts and floods, have a much greater effect on salmonid abundance in GRSM than do regulations or fishing pressure.