The inter-annual variability in year class strength (1976-2000) of North Sea herring (Clupea harengus) was investigated using Paulik diagrams based on survey data and Virtual Population Analysis. The herring life cycle was split into five stages: spawning stock biomass (SSB), egg production, larvae, fish with 0 winter rings on the otolith (0-wr), 1...
A sensitivity analysis of a multispecies virtual population analysis (MSVPA) model parameterized for the Bering Sea was carried out using two methods for the analysis. In the first method, four variables related to the predation mortality M2 and population size of age-1 walleye pollock (Theragra chalcogramma) and Pacific cod (Gadus macrocephalus) w...
Published in Russian Journal of Marine Biology
Geographic and interannual variability of the number of annuli and the radius of the first scale annulus, as well as the retrospective length of year-old walleye pollock from the western, northern, and eastern parts of the Bering Sea, was examined using data for the years 1995, 1996, 1998, and 1999. The characteristics of the first scale annulus we...
Published in Environmental Biology of Fishes
It is widely held that when predator avoidance conflicts with other activities, such as feeding, avoidance of predators often takes precedence. In this study, we examine how predation risk and food distribution interact to influence the schooling behavior and swimming speed of foraging juvenile walleye pollock, Theragra chalcogramma. Fish were accl...
