Growth of white catfish in California's Sacramento San Joaquin Delta

California's Sacramento-San Joaquin Delta is inhabited by one of the slowest growing populations of white catfish, Ameiurus catus, yet reported. White catfish in the south and central delta grow more slowly than fish in the north and west delta. At age 8, white catfish in the south and central delta reach only 253 mm fork length; fish from the north and west delta are 284 mm long at the same age. After age 4, males grow faster than females in the south and central delta, but not in other areas. Lack of an adequate forage base for larger fish and high population densities may be responsible for slow growth. While angling regulations have been changed to increase harvest and, potentially, reduce density, meaningful increases in catch would probably require changes in allowable fishing gear that may adversely impact other species.