Document Type

Thesis

Abstract

The biomass of Prince William Sound herring (Clupea pallasi) is estimated from egg deposition surveys. Because surveys occur after spawning, a correction for egg loss is required. I constructed ANOVA models based on environmental factors to estimate the egg loss correction in 1990-1991 and 1994-1995. The models explained 52% to 85% of the data variation. Depth of spawn was the primary factor determining egg loss, and air exposure could be substituted for depth. The correction factor was estimated at 33%. The total loss of eggs from spawning to hatching ranged from 67.40% to 100% averaging 76.06%, Two processes affecting egg loss, wave action and fish predation, were also examined. Typical wave energies were not found to contribute significantly to egg loss, but a threshold wave energy may exist beyond which egg loss is high. Consumption of eggs by greenling (Hexagrammidae) was estimated at 2.2% to 8.5% of the total spawn.

Publication Date

8-17-1996

Handle

http://hdl.handle.net/11122/5283

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