Declining Rockfish Lengths in the Monterey Bay,
California Recreational Fishery, 1959-94

Marine Fisheries Review (Vol. 60, No.3) July 1999.

Background: This is the second manuscript published on this fishery. The first one, published in 1995, "Species Trends in Sport Fisheries, Monterey Bay, California, 1959-86", (Marine Fisheries Review 57 (1) ) examined changes in the species composition in relation to fishing location and depth. The new manuscript describes the declining size of the dominant rockfish species in the CPFV fishery.

Purpose of Activity/Goal of Project: Examine the declines in size of rockfish in a 30 year perspective to detect long term fishery effects beyond the variability induced by sporadic recruitment.

Description of Accomplishment and Significant Results: California's Monterey Bay area is an important center of recreational as well as commercial fishing for rockfish of various Sebastes species. Until the late 1970's the commercial and recreational fisheries utilized different species from different depths, but in recent years the commercial passenger fishing vessels (CPFVs) have fished in deeper waters. The shift from shallow nearshore locations to deeper offshore locations changed the emphasis from the blue rockfish, S. mystinus, of shallow waters to the deeper, commercially fished chilipepper S. goodei, and bocaccio, S. paucispinis. CPFVs caught, on average, 9% of the combined annual commercial and CPFV landings of chilipepper and bocaccio at Monterey Bay ports during 1980-94. The mean size of rockfish in the CPFV catch increased as large chilipepper and bocaccio were targeted, but then declined as stocks of older fish disappeared in the mid 1980's. During 1960-94 the mean size of all ten leading species in the recreational catch declined. The declines ranged from 1% for canary rockfish, S. pinniger, to 27% for chilipepper. The sizes of the deeper living, primarily commercial species declined more than those of shallower recreationally caught species. The low frequency of strong recruitment events and increases in both fishing mortality and natural mortality (during the 1982-83 El Niño) appear to have contributed to the declining mean size. The scarcity of older fish, observed as a drop in mean size to below the size of maturity for 50% of females, leads to concern for future recruitment of the larger species, especially bocaccio, chilipepper, yellowtail rockfish, S. flavidus, and canary rockfish.

Significance of Accomplishment (e.g., to the Center, to Management, and to NMFS Strategic Plan Goals): This work shows how the Monterey Bay CPFV fishery contributes to impacts on the sustainability of PFMC-managed rockfish species, especially bocaccio and chilipepper.

Problems: None.

Key Contact: Janet Mason (831-648-9028,